Nanowires have emerged as promising one-dimensional materials with which to construct various nanocircuits and nanosensors.However,measuring the electrical properties of individual nanowires directly remains challengi...Nanowires have emerged as promising one-dimensional materials with which to construct various nanocircuits and nanosensors.However,measuring the electrical properties of individual nanowires directly remains challenging because of their small size,thereby hindering the comprehensive understanding of nanowire-based device performance.A crucial factor in achieving reliable electrical characterization is establishing well-determined contact conditions between the nanowire sample and the electrodes,which becomes particularly difficult for soft nanowires.Introduced here is a novel technique for measuring the conductivity of an individual nanowire with the aid of automated nanomanipulation using an atomic force microscope.In this method,two nanowire segments cut from the same silver nanowire are positioned onto a pair of gold electrodes,serving as flexible nanoprobes to establish controllable contact with the sample.By changing the contact points along the nanowire sample,conductivity measurements can be performed on different regions,thereby eliminating the influence of contact resistance by analyzing multiple current–voltage curves.Using this approach,the resistivity of a 100-nm-diameter silver nanowire is determined to be 3.49×10^(−8)Ωm.展开更多
Carbon dots(CDs), as a new member of carbon nanomaterial family, have aroused great interest since their discovery in 2004. Because of their outstanding water solubility, high sensitivity and selectivity to target ana...Carbon dots(CDs), as a new member of carbon nanomaterial family, have aroused great interest since their discovery in 2004. Because of their outstanding water solubility, high sensitivity and selectivity to target analytes, low toxicity, favorable biocompatibility, and excellent photostability, researchers from diverse disciplines have come together to further develop the fundamental properties of CDs. Many methods for the production of CDs have been reported, therein, hydrothermal and solvothermal technology needs simple equipments, and microwave synthesis needs less reaction time, hence these methods become current common synthesis methods, in which many precursors have been applied to produce CDs. Due to their excellent fluorescence, CDs have made impressive strides in sensitivity and selectivity to a diverse array of salt ions,organic/biological molecules and target gases. The development of CDs as nanoprobes is still in its infancy, but continued progress may lead to their integration into environmental and biological applications. Hydrothermal,solvothermal, and microwave synthesis of fluorescent carbon dots and their detection applications as nanoprobes in salt ions, organic/biological molecules, and target gases will be reviewed.展开更多
In this paper, near-infrared emitting long-persistence luminescent Zn3Ga2Ge2O10:Cr3?(ZGG) nanoparticles with diameters of 30–100 nm and bright luminescence were prepared by a sol–gel synthesis method. After the surf...In this paper, near-infrared emitting long-persistence luminescent Zn3Ga2Ge2O10:Cr3?(ZGG) nanoparticles with diameters of 30–100 nm and bright luminescence were prepared by a sol–gel synthesis method. After the surface amination, the nanoparticles were further bioconjugated with breast cancer-specific monoclonal antibody(anti-Ep CAM) to form ZGG-Ep CAM nanoprobes which can specifically target breast cancer cell lines(MCF7) in vitro. The results of in vitro images show that the luminescence signals from the cells treated with ZGG-Ep CAM nanoprobes are stronger than those from cells treated with ZGG-unconjugated antibody, indicating that the prepared ZGG-Ep CAM nanoprobes possessed excellent specific recognition capability. Furthermore, due to their long afterglow properties, the imaging could persist more than 1 h. Therefore, these nanoprobes could not only provide a high specificity detection method for cancer cells but also realize the long-time monitoring. Developed near-infrared emitting long-persistence luminescent nanoprobes will be expected to find new perspectives for cell therapy research and diagnosis applications.展开更多
Fe-based single-atomic site catalysts(SASCs),with the natural metalloproteases-like active site structure,have attracted widespread attention in biocatalysis and biosensing.Precisely,controlling the isolated single-at...Fe-based single-atomic site catalysts(SASCs),with the natural metalloproteases-like active site structure,have attracted widespread attention in biocatalysis and biosensing.Precisely,controlling the isolated single-atom Fe-N-C active site structure is crucial to improve the SASCs’performance.In this work,we use a facile ion-imprinting method(IIM)to synthesize isolated Fe-N-C single-atomic site catalysts(IIM-Fe-SASC).With this method,the ion-imprinting process can precisely control ion at the atomic level and form numerous well-defined single-atomic Fe-N-C sites.The IIM-Fe-SASC shows better peroxidase-like activities than that of non-imprinted references.Due to its excellent properties,IIM-Fe-SASC is an ideal nanoprobe used in the colorimetric biosensing of hydrogen peroxide(H_(2)O_(2)).Using IIM-Fe-SASC as the nanoprobe,in situ detection of H_(2)O_(2)generated from MDA-MB-231 cells has been successfully demonstrated with satisfactory sensitivity and specificity.This work opens a novel and easy route in designing advanced SASC and provides a sensitive tool for intracellular H_(2)O_(2)detection.展开更多
How to trigger strong anti-tumor immune responses has become a focus for tumor therapy.Here,we report the human-induced pluripotent stem cells(iPSs)to deliver MnO2@Ce6 nanoprobes into tumors for simultaneous photodyna...How to trigger strong anti-tumor immune responses has become a focus for tumor therapy.Here,we report the human-induced pluripotent stem cells(iPSs)to deliver MnO2@Ce6 nanoprobes into tumors for simultaneous photodynamic therapy(PDT)and enhanced immunotherapy.Ce6 photosensitizer was attached on manganese dioxide(MnO2)nanoparticles,and resultant MnO2@Ce6 nanoprobes were delivered into mitomycin-treated iPSs to form iPS-MnO2@Ce6 nanoprobes.The iPS-MnO2@Ce6 actively targeted in vivo tumors,the acidic microenvironment triggered interaction between MnO2 and H2O2,released large quantities of oxygen,alleviated hypoxia in tumor.Upon PDT,singlet oxygen formed,broken iPSs released tumor-shared antigens,which evoked an intensive innate and adaptive immune response against the tumor,improving dendritic cells matured,effector T cells,and natural killer cells were activated.Meanwhile,regulatory T cells were reduced,and then the immune response induced by iPS-MnO2@Ce6 was markedly stronger than the immune reaction induced by MnO2@Ce6(P<0.05).The iPS-MnO2@Ce6 markedly inhibited tumor growth and metastasis and reduced mortality in mice models with tumor.Human iPS s loaded with MnO2-based nanoprobes are a promising strategy for simultaneous PDT and enhanced immunotherapy against tumor and own clinical translational prospect.展开更多
Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for cancer.However,serious toxic side effects caused by long-term drug accumulation can cause significant ...Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for cancer.However,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor drugs.In this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is reduced.The unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe complex.In addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor environment.The change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic effect.In vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in tumors.This work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.展开更多
Malignant tumors are the main diseases threatening human life. Using precise theranostics to diagnose and cure tumors has emerged as a new method to improve patient survival. Based on the current development of precis...Malignant tumors are the main diseases threatening human life. Using precise theranostics to diagnose and cure tumors has emerged as a new method to improve patient survival. Based on the current development of precise tumor imaging, image-guided tumor therapy has received widespread attention because it is beneficial for developing precise treatment of tumors, has the potential to improve the efficacy of tumor therapy and reduce the incidence of adverse side effects. Nanoprobes, which are nanomaterial functionalized with specific biomolecules, have intrigued intense interest due to their great potential in monitoring biorecognition and biodetection evens. Benefiting from the unique advantages of nanomaterials, including the easy surface functionalization, the unique imaging performances, and the high drug loading capacity, nanoprobes have become a powerful tool to simultaneously realize tumor precise imaging, diagnosis, and therapy. This review introduces the non-invasive tumor precise imaging and highlights the recent advances of image-guided oncotherapy mediated by nanoprobes in anti-tumor drug delivery, tumor precise surgical navigation, chemodynamic therapy, and phototherapy. Finally, a perspective on the challenge and future direction of nanoprobes in imaging-guided tumor theranostics is also discussed.展开更多
The development of microenvironment-responsive nanoprobes has shown great promise for use in magnetic resonance imaging(MRI),with the advantage of significantly improved specificity and good biocompatibility.However,t...The development of microenvironment-responsive nanoprobes has shown great promise for use in magnetic resonance imaging(MRI),with the advantage of significantly improved specificity and good biocompatibility.However,the clinical application of responsive probes is hampered by a lack of biological sensitivity for early molecular diagnostics and visualizing microenvionment of metabolism reprogramming in tumor progression.Here,we report on a dual-ratiometric magnetic resonance tunable(DMRT)nanoprobe designed by crosslinking different ratios of transferrin chelating gadolinium and superparamagnetic nanoparticles,complexed to a pH responsive biocompatible polymer.This dually activatable nanoprobe enables pH-dependent tumor microenvironment visualization,providing exceptional quantitative pathophysiological information in vitro and in vivo.When used in combination with dual-contrast enhancement triple subtraction imaging technique(DETSI),this smart nanoprobe guarantees the diagnosis of early-stage diseases.We envisage that this novel integrated nanoplatform will provide a new paradigm for the clinical translation of robust DMRT nanoprobes for early disease detection and staging,as well as microenvironment visualization and disease progression monitoring.展开更多
Breast cancer is one of the most prevalent cancers worldwide,and early diagnosis and screening are vital to its successful treatment.Although medical imaging methods can assist in the early detection of breast cancer,...Breast cancer is one of the most prevalent cancers worldwide,and early diagnosis and screening are vital to its successful treatment.Although medical imaging methods can assist in the early detection of breast cancer,imaging methods that are currently used for clinical diagnosis have drawbacks,such as low sensitivity and accuracy.Contrast agents are often used in diagnostic imaging to address these drawbacks.Nanocontrast agents have attracted considerable attention in recent years due to their unique physicochemical characteristics.Among these agents,inorganic nanoprobes have been substantially developed through improvements in synthesis techniques and pairings with other organic molecules.This paper mainly summarizes the specific applications of inorganic nanoprobes in the magnetic resonance imaging,fluorescence imaging,radionuclide imaging,and bimodal/multimodal imaging of breast cancer.展开更多
Persistent luminescence nanoprobes (PLNPs) can remain luminescent after ceasing excitation.Due to the ultra-long decay time of persistent luminescence (PersL),autofluorescence interference can be efficiently eliminate...Persistent luminescence nanoprobes (PLNPs) can remain luminescent after ceasing excitation.Due to the ultra-long decay time of persistent luminescence (PersL),autofluorescence interference can be efficiently eliminated by collecting PersL signal after autofluorescence decays completely,thus the imaging contrast and sensing sensitivity can be significantly improved.Since near-infrared (NIR) light shows reduced scattering and absorption coefficient in penetrating biological organs or tissues,near-infrared persistent luminescence nanoprobes (NIR PLNPs) possess deep tissue penetration and offer a bright prospect in the areas of in vivo biosensing/bioimaging.In this review,we firstly summarize the design of different types of NIR PLNPs for biosensing/bioimaging,such as transition metal ions-doped NIR PLNPs,lanthanide ions-doped NIR PLNPs,organic molecules-based NIR PLNPs,and semiconducting polymer self-assembled NIR PLNPs.Notably,organic molecules-based NIR PLNPs and semiconductor self-assembled NIR PLNPs,for the first time,were introduced to the review of PLNPs.Secondly,the effects of different types of charge carriers on NIR PersL and luminescence decay of NIR PLNPs are significantly emphasized so as to build up an in-depth understanding of their luminescence mechanism.It includes the regulation of valence band and conduction band of different host materials,alteration of defect types,depth and concentration changes caused by ion doping,effective radiation transitions and energy transfer generated by different luminescence centers.Given the design and potential of NIR PLNPs as long-lived luminescent materials,the current challenges and future perspective in this rapidly growing field are also discussed.展开更多
Cellular redox status presents broad implications with diverse physiological and pathological processes. Simultaneous detection of both the oxidative and reductive species of redox couples, especially the most represe...Cellular redox status presents broad implications with diverse physiological and pathological processes. Simultaneous detection of both the oxidative and reductive species of redox couples, especially the most representative pair glutathione/hydrogen peroxide (GSH/H2O2), is crucial to accurately map the cellular redox status. However, it still remains challenging to synchronously detect GSH/H2O2 in vivo due to lack of a reliable measuring tool. Herein, a ratiometric nanoprobe (UCNP-TB) possessing simultaneous delectability of GSH/H2O2 is established based on a multi-spectral upconverti ng nano phosphor (UCNP-OA) as the lumin esce nee res onance energy tran sfer (LRET) donor and two dye molecules as the acceptors, including a GSH-sensitive dye (TCG) and a H2O2-sensitive dye (BCH). With the as-prepared UCNP-TB, real-time and synchronous monitoring the variation of GSH and H2O2 in vitro and in living mice can be achieved using the ratio of the upcon versi on lumin esce nee (UCL) at 540 and 650 nm to that at 800 nm as the detecti on sign al, respectively, providi ng highly inhere nt reliability of the sensing results by self-calibrati on. Moreover, the nan oprobe is capable of mappi ng the redox status within the drug-resista nt tumor and the drug-induced hepatotoxic liver via ratiometric UCL imaging. Thus, this nan oprobe would provide a reliable tool to elucidate the redox state in vivo.展开更多
Inorganic luminescent nanocrystals(NCs)doped with main-group ns^(2)-metal ions have evoked tremendous interest in many technological fields owing to their superior optical properties.Herein,we report a new class of lu...Inorganic luminescent nanocrystals(NCs)doped with main-group ns^(2)-metal ions have evoked tremendous interest in many technological fields owing to their superior optical properties.Herein,we report a new class of luminescent nanoprobes based on 5s2-metal Sb3+-doped CaS NCs that are excitable by using a near ultraviolet light-emitting diode.The optical properties and excited-state dynamics of Sb3+in CaS NCs are comprehensively surveyed through temperature-dependent steady-state and transient photoluminescence(PL)spectroscopies.Owing to the strong electron-phonon coupling of Sb^(3+)in CaS NCs,Sb3+ions experience a dynamic Jahn-Taller distortion on the excited state,which results in bright green PL of Sb3+with a broad emission band,a large Stokes shift,and a high PL quantum yield up to 17.3%.By taking advantage of the intense PL of Sb^(3+),we show in proof-of-concept experiments the application of biotinylated CaS:Sb^(3+)NCs as sensitive luminescent nanoprobes for biotin receptor-targeted cancer cell imaging and zebrafish imaging with a high imaging contrast.These findings provide fundamental insights into the excited-state dynamics of Sb^(3+)in CaS NCs,thus laying a foundation for future design of novel and versatile luminescent nanoprobes via main-group ns2-metal doping.展开更多
CuInS2 semiconductor nanocrystals (NCs) exhibit large absorption coefficient, size-dependent photoluminescence and low toxicity, making them excellent candidates in a variety of bioapplications. However, precise contr...CuInS2 semiconductor nanocrystals (NCs) exhibit large absorption coefficient, size-dependent photoluminescence and low toxicity, making them excellent candidates in a variety of bioapplications. However, precise control of both their composition and morphology to improve the luminescent efficiency remains a great challenge via conventional direct synthesis. Herein, we present a novel low-temperature template synthesis of highly efficient luminescent CuInS2 nanoprobes from In2S3 NCs via a facile cation exchange strategy. The proposed strategy enables synthesis of a series of CuInS2 NCs with broad size tunability from 2.2 to 29.6 nm. Through rationally manipulating the stoichiometry of Cu/In, highly efficient luminescence of CuInS2 with the maximum quantum yield of 28.6% has been achieved, which is about one order of magnitude improvement relative to that of directly synthesized NCs. By virtue of the intense emission of CuInS2 nanoprobes, we exemplify their application in sensitive homogeneous biodetection for an important biomolecule of adenosine triphosphate (ATP) with the limit of detection down to 49.3 nM. Moreover, the CuInS2 nanoprobes are explored for ATP-targeted cancer cell imaging, thus revealing their great potentials in the field of cancer diagnosis and prognosis.展开更多
In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can b...In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can be efficiently imbibed during the growing process and the absorbance presented a position dependence effect, which was supported by the upconversion spectra and the fluorescent image characterization. In addition, the concentration of the residual RhB in bean sprout can be efficiently traced by the synthesized probe based on the fluorescent resonant energy transfer. Finally, the relation between the excitation power, concentration and the ratio of yellow to green emission are discussed in detail. These results can be helpful in understanding the RhB dye molecules absorbance process in vegetable growth and provide an efficient way to trace the residual dyes in vivo plant.展开更多
Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications o...Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications of Raman imaging. By adsorbing Raman molecules onto specific nanostructures such as noble metals, Raman signals can be significantly enhanced, termed surfaceenhanced Raman scattering(SERS). Recent years have witnessed great interest in the development of SERS nanoprobes for Raman imaging. Rationally designed SERS nanoprobes have greatly enhanced Raman signals by several orders of magnitude, thus showing great potential for biomedical applications.In this review we elaborate on recent progress in design strategies with emphasis on material properties,modifying factors, and structural parameters.展开更多
The immense potential of carbon nanoprobes(CNPs)for using as contrast agents has propelled much recent research and development in the field of thermoacoustic(TA)molecular imaging,while the proper engineering and desi...The immense potential of carbon nanoprobes(CNPs)for using as contrast agents has propelled much recent research and development in the field of thermoacoustic(TA)molecular imaging,while the proper engineering and design of such materials with required high TA conversion efficiency is still a highly challenging task.In this work,we proposed a controllable strategy to amplify the TA conversion efficiency of the CNPs by constructing vacancy defect(VD)dipoles,and systematically demonstrated the amplification mechanism through theoretical and experimental investigations.First-principles calculation results indicate that,when a carbon atom is removed from the CNPs by chemical approach,owing to local electron density redistribution,the VDs are formed at the positions of the original carbon atoms and act as the structural origin of permanent electric dipoles with the dipole moment several orders higher than that of non-defect sites.Under pulsed microwave irradiation,the VD dipoles are polarized repeatedly and significantly contribute to the conversion efficiency from absorbed electromagnetic waves to ultrasound through enhanced dielectric relaxation losses.We experimentally synthesized graphene samples with different VD densities and VD types to demonstrate the efficiency of the proposed strategy,and results coincide well with the theoretical proposition.This work offers feasible guidance to the systematic development and rational design of new high-conversion-efficiency TA CNPs via VD engineering.展开更多
High-sensitivity detection of porphyrin in blood is very important for the early diagnosis and treatment of porphyria.Based on the advantages of longer luminescence lifetime and lower background interference,organic a...High-sensitivity detection of porphyrin in blood is very important for the early diagnosis and treatment of porphyria.Based on the advantages of longer luminescence lifetime and lower background interference,organic afterglow molecular porphyrin detection probes were developed,but these probes show poor water solubility and insufficient luminescence intensity.Herein,we present an afterglow nanoprobe(Eu-NP)for porphyria detection in whole blood.The luminescent substance(europium complex)and the organic vinyl co mpound reacted with singlet oxygen(^(1)O_(2))were selected for encapsulation in polystyrene spheres.Eu-NP can respond to^(1)O_(2)produced by porphyrins,and the detection signals can be obtained by the emission of the afterglow Eu^(3+)-emissive nanosensor.Eu-NP can achieve high-sensitivity detection of porphyrin,and the lowest detection limit reaches 0.29μmol/L.The porphyrin detection in whole blood samples is consistent with clinical diagnosis results.Compared with the organic afterglow molecule,the Eu-NPs constructed in this work show a higher signal-to-noise ratio and sensitivity of porphyria detection.展开更多
Mitophagy has a critical role in maintaining cellular homeostasis through acidic lysosomes engulfing excess or impaired mitochondria,thereby pH fluctuation is one of the most significant indicators for tracking mitoph...Mitophagy has a critical role in maintaining cellular homeostasis through acidic lysosomes engulfing excess or impaired mitochondria,thereby pH fluctuation is one of the most significant indicators for tracking mitophagy.Then such precise pH tracking demands the fluorogenic probe that has tailored contemporaneous features,including mitochondrial-specificity,excellent biocompatibility,wide pH-sensitive range of 8.0–4.0,and especially quantitative ability.However,available molecular probes cannot simultaneously meet all the requirements since it is extremely difficult to integrate multiple functionalities into a single molecule.To fully address this issue,we herein integrate two fluorogenic pH sensitive units,a mitochondria-specific block,cellpenetrating facilitator,and biocompatible segments into an elegant silica nano scaffold,which greatly ensures the applicability for real-time tracking of pH fluctuations in mitophagy.Most significantly,at a single wavelength excitation,the integrated pHsensitive units have spectra-distinguishable fluorescence towards alkaline and acidic pH in a broad range that covers mitochondrial and lysosomal pH,thus enabling a ratiometric analysis of pH variations during the whole mitophagy.This work also provides constructive insights into the fabrication of advanced fluorescent nanoprobes for diverse biomedical applications.展开更多
A ratiometric fluorescent hybrid nanoprobe CDs-1 for arginine(Arg),exhibiting high sensitivity(the limit of detection,LOD,being 6.5×10^-8 mol/L) and excellent selectivity and anti-interference ability,was fabrica...A ratiometric fluorescent hybrid nanoprobe CDs-1 for arginine(Arg),exhibiting high sensitivity(the limit of detection,LOD,being 6.5×10^-8 mol/L) and excellent selectivity and anti-interference ability,was fabricated through fluorescence resonance energy transfer(FRET) and the electrostatic attraction between positively-charged hemicyanine molecules and negatively-charged carbon dots(CDs).Arg can be quantitatively detected in the concentration range from 6.0×10^-5 mol/L to 2.7×10^-4 mol/L.Further,due to its ability to target mitochondrion and low cytotoxicity,intracellular Arg was succes s fully tracked through ratiometric fluorescence imaging.展开更多
Ascorbic acid(AA) serves as a key coenzyme in many metabolic pathways. Enough daily AA supplements from different dietary sources are the only way for human to maintain their AA levels in body.Determination of AA cont...Ascorbic acid(AA) serves as a key coenzyme in many metabolic pathways. Enough daily AA supplements from different dietary sources are the only way for human to maintain their AA levels in body.Determination of AA content in different foods guides to build healthy diet, which is of great biomedical significance. Hence, developing a highly selective and instantaneous fluorescent nanoprobe for the detection of AA in biological samples is highly needed. Here we present a novel turn-on fluorescent nanoprobe using lanthanide-doped upconversion nanoparticles(UCNPs) and cobalt oxyhydroxide(Co OOH) nanoflakes for monitoring AA in fruit samples. In this nanosystem, the UCNPs can be adsorbed onto the Co OOH nanoflakes, leading to a remarkable fluorescence decrease through Fo?rster resonance energy transfer. Furthermore, the AA could trigger the disassembly of the Co OOH to liberate the upconverted fluorescence. The UCNPs-based nanoprobe can provide an effective platform for highly selective and rapid detection of AA in biological samples.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61973233).
文摘Nanowires have emerged as promising one-dimensional materials with which to construct various nanocircuits and nanosensors.However,measuring the electrical properties of individual nanowires directly remains challenging because of their small size,thereby hindering the comprehensive understanding of nanowire-based device performance.A crucial factor in achieving reliable electrical characterization is establishing well-determined contact conditions between the nanowire sample and the electrodes,which becomes particularly difficult for soft nanowires.Introduced here is a novel technique for measuring the conductivity of an individual nanowire with the aid of automated nanomanipulation using an atomic force microscope.In this method,two nanowire segments cut from the same silver nanowire are positioned onto a pair of gold electrodes,serving as flexible nanoprobes to establish controllable contact with the sample.By changing the contact points along the nanowire sample,conductivity measurements can be performed on different regions,thereby eliminating the influence of contact resistance by analyzing multiple current–voltage curves.Using this approach,the resistivity of a 100-nm-diameter silver nanowire is determined to be 3.49×10^(−8)Ωm.
基金supported by the National HighTech R&D Program of China (863 program, 2011AA050504)National Natural Science Foundation of China (21171117 and 61376003)+4 种基金Program for New Century Excellent Talents in University (NCET-12-0356)Shanghai Natural Science Foundation (13ZR1456600)Shanghai Science and Technology Grant (12JC1405700)Shanghai Pujiang Program (11PJD011)the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, and Medical-Engineering Crossover Fund (YG2012MS40 and YG2012MS32) of Shanghai Jiao Tong University
文摘Carbon dots(CDs), as a new member of carbon nanomaterial family, have aroused great interest since their discovery in 2004. Because of their outstanding water solubility, high sensitivity and selectivity to target analytes, low toxicity, favorable biocompatibility, and excellent photostability, researchers from diverse disciplines have come together to further develop the fundamental properties of CDs. Many methods for the production of CDs have been reported, therein, hydrothermal and solvothermal technology needs simple equipments, and microwave synthesis needs less reaction time, hence these methods become current common synthesis methods, in which many precursors have been applied to produce CDs. Due to their excellent fluorescence, CDs have made impressive strides in sensitivity and selectivity to a diverse array of salt ions,organic/biological molecules and target gases. The development of CDs as nanoprobes is still in its infancy, but continued progress may lead to their integration into environmental and biological applications. Hydrothermal,solvothermal, and microwave synthesis of fluorescent carbon dots and their detection applications as nanoprobes in salt ions, organic/biological molecules, and target gases will be reviewed.
基金supported by the Science and Technology Project in Xiamen(3502Z20132012)the Xiamen Southern Oceanographic Center(14GYY008NF08)+2 种基金the Natural Science Foundation of Fujian Province(2011J01220)the Major Program of Department of Science and Technology(2012Y4009)the Science and Technology Planning Project of Xiamen(3502Z20123036)
文摘In this paper, near-infrared emitting long-persistence luminescent Zn3Ga2Ge2O10:Cr3?(ZGG) nanoparticles with diameters of 30–100 nm and bright luminescence were prepared by a sol–gel synthesis method. After the surface amination, the nanoparticles were further bioconjugated with breast cancer-specific monoclonal antibody(anti-Ep CAM) to form ZGG-Ep CAM nanoprobes which can specifically target breast cancer cell lines(MCF7) in vitro. The results of in vitro images show that the luminescence signals from the cells treated with ZGG-Ep CAM nanoprobes are stronger than those from cells treated with ZGG-unconjugated antibody, indicating that the prepared ZGG-Ep CAM nanoprobes possessed excellent specific recognition capability. Furthermore, due to their long afterglow properties, the imaging could persist more than 1 h. Therefore, these nanoprobes could not only provide a high specificity detection method for cancer cells but also realize the long-time monitoring. Developed near-infrared emitting long-persistence luminescent nanoprobes will be expected to find new perspectives for cell therapy research and diagnosis applications.
基金This work was supported by a WSU startup fund.XAS measurements were done at beamline 12-BM of the Advanced Photon Source(APS),which is a User Facility operated for the U.S.Department of Energy Office of Science by Argonne National Laboratory under Contract DE-AC02-06CH11357.
文摘Fe-based single-atomic site catalysts(SASCs),with the natural metalloproteases-like active site structure,have attracted widespread attention in biocatalysis and biosensing.Precisely,controlling the isolated single-atom Fe-N-C active site structure is crucial to improve the SASCs’performance.In this work,we use a facile ion-imprinting method(IIM)to synthesize isolated Fe-N-C single-atomic site catalysts(IIM-Fe-SASC).With this method,the ion-imprinting process can precisely control ion at the atomic level and form numerous well-defined single-atomic Fe-N-C sites.The IIM-Fe-SASC shows better peroxidase-like activities than that of non-imprinted references.Due to its excellent properties,IIM-Fe-SASC is an ideal nanoprobe used in the colorimetric biosensing of hydrogen peroxide(H_(2)O_(2)).Using IIM-Fe-SASC as the nanoprobe,in situ detection of H_(2)O_(2)generated from MDA-MB-231 cells has been successfully demonstrated with satisfactory sensitivity and specificity.This work opens a novel and easy route in designing advanced SASC and provides a sensitive tool for intracellular H_(2)O_(2)detection.
基金financially supported by National Nature Scientific foundation(81803094,81802979 and 81921002)the National Foundational Basic Research Project of China(2017YFA0205301 and 2015CB931802)+3 种基金Shanghai Municipal Commission of Economy and Information Technology Fund(No.XC-ZXSJ-02-2016-05)the medical engineering cross project of Shanghai Jiao Tong university(YG2017ZD05,YG2016ZD10 and YG2017Z D05)the Project of Thousand Youth Talents from Chinathe National Key Research and Development Program of China(2017YFC1200904 and 2017YFE0124400)。
文摘How to trigger strong anti-tumor immune responses has become a focus for tumor therapy.Here,we report the human-induced pluripotent stem cells(iPSs)to deliver MnO2@Ce6 nanoprobes into tumors for simultaneous photodynamic therapy(PDT)and enhanced immunotherapy.Ce6 photosensitizer was attached on manganese dioxide(MnO2)nanoparticles,and resultant MnO2@Ce6 nanoprobes were delivered into mitomycin-treated iPSs to form iPS-MnO2@Ce6 nanoprobes.The iPS-MnO2@Ce6 actively targeted in vivo tumors,the acidic microenvironment triggered interaction between MnO2 and H2O2,released large quantities of oxygen,alleviated hypoxia in tumor.Upon PDT,singlet oxygen formed,broken iPSs released tumor-shared antigens,which evoked an intensive innate and adaptive immune response against the tumor,improving dendritic cells matured,effector T cells,and natural killer cells were activated.Meanwhile,regulatory T cells were reduced,and then the immune response induced by iPS-MnO2@Ce6 was markedly stronger than the immune reaction induced by MnO2@Ce6(P<0.05).The iPS-MnO2@Ce6 markedly inhibited tumor growth and metastasis and reduced mortality in mice models with tumor.Human iPS s loaded with MnO2-based nanoprobes are a promising strategy for simultaneous PDT and enhanced immunotherapy against tumor and own clinical translational prospect.
基金Project supported by the National Natural Science Foundation of China(92159103)Beijing Municipal Education Commission Outstanding Young Individual Project(CIT&TCD201904082)+1 种基金Youth High-level Talent Project of Capital Normal University(20530810024)Yanjing Young Scholar Program of Capital Normal University。
文摘Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for cancer.However,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor drugs.In this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is reduced.The unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe complex.In addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor environment.The change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic effect.In vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in tumors.This work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.
基金the National Key R&D Program of China(No.2020YFA0908800)the National Natural Science Foundation of China(Nos.22174105 and 21974104)Large-scale Instrument and Equipment Sharing Foundation of Wuhan University.
文摘Malignant tumors are the main diseases threatening human life. Using precise theranostics to diagnose and cure tumors has emerged as a new method to improve patient survival. Based on the current development of precise tumor imaging, image-guided tumor therapy has received widespread attention because it is beneficial for developing precise treatment of tumors, has the potential to improve the efficacy of tumor therapy and reduce the incidence of adverse side effects. Nanoprobes, which are nanomaterial functionalized with specific biomolecules, have intrigued intense interest due to their great potential in monitoring biorecognition and biodetection evens. Benefiting from the unique advantages of nanomaterials, including the easy surface functionalization, the unique imaging performances, and the high drug loading capacity, nanoprobes have become a powerful tool to simultaneously realize tumor precise imaging, diagnosis, and therapy. This review introduces the non-invasive tumor precise imaging and highlights the recent advances of image-guided oncotherapy mediated by nanoprobes in anti-tumor drug delivery, tumor precise surgical navigation, chemodynamic therapy, and phototherapy. Finally, a perspective on the challenge and future direction of nanoprobes in imaging-guided tumor theranostics is also discussed.
基金This work was supported by the National Natural Science Foundation of China(Nos.81971664 and 82272057)the Shanghai Pujiang Program(No.2019PJD044).
文摘The development of microenvironment-responsive nanoprobes has shown great promise for use in magnetic resonance imaging(MRI),with the advantage of significantly improved specificity and good biocompatibility.However,the clinical application of responsive probes is hampered by a lack of biological sensitivity for early molecular diagnostics and visualizing microenvionment of metabolism reprogramming in tumor progression.Here,we report on a dual-ratiometric magnetic resonance tunable(DMRT)nanoprobe designed by crosslinking different ratios of transferrin chelating gadolinium and superparamagnetic nanoparticles,complexed to a pH responsive biocompatible polymer.This dually activatable nanoprobe enables pH-dependent tumor microenvironment visualization,providing exceptional quantitative pathophysiological information in vitro and in vivo.When used in combination with dual-contrast enhancement triple subtraction imaging technique(DETSI),this smart nanoprobe guarantees the diagnosis of early-stage diseases.We envisage that this novel integrated nanoplatform will provide a new paradigm for the clinical translation of robust DMRT nanoprobes for early disease detection and staging,as well as microenvironment visualization and disease progression monitoring.
基金supported by the National Natural Science Foundation of China(82172044,22006109)the Medical Scientific Research Project of Jiangsu Provincial Health Commission(H2019086)+1 种基金the Postdoctoral Foundation of Jiangsu Province(2020Z372)Suzhou Medical Innovation Application Research Project(SKY2022104),China.
文摘Breast cancer is one of the most prevalent cancers worldwide,and early diagnosis and screening are vital to its successful treatment.Although medical imaging methods can assist in the early detection of breast cancer,imaging methods that are currently used for clinical diagnosis have drawbacks,such as low sensitivity and accuracy.Contrast agents are often used in diagnostic imaging to address these drawbacks.Nanocontrast agents have attracted considerable attention in recent years due to their unique physicochemical characteristics.Among these agents,inorganic nanoprobes have been substantially developed through improvements in synthesis techniques and pairings with other organic molecules.This paper mainly summarizes the specific applications of inorganic nanoprobes in the magnetic resonance imaging,fluorescence imaging,radionuclide imaging,and bimodal/multimodal imaging of breast cancer.
基金the National Natural Science Foundation of China (NSFC,No.21675120)the National Key R&D Program of China (Nos.2017YFA0208000 and 2016YFF0100800)+1 种基金Foundation for Innovative Research Groups of NSFC (No.21521063)the National Basic Research Program of China (No.2015CB932600).
文摘Persistent luminescence nanoprobes (PLNPs) can remain luminescent after ceasing excitation.Due to the ultra-long decay time of persistent luminescence (PersL),autofluorescence interference can be efficiently eliminated by collecting PersL signal after autofluorescence decays completely,thus the imaging contrast and sensing sensitivity can be significantly improved.Since near-infrared (NIR) light shows reduced scattering and absorption coefficient in penetrating biological organs or tissues,near-infrared persistent luminescence nanoprobes (NIR PLNPs) possess deep tissue penetration and offer a bright prospect in the areas of in vivo biosensing/bioimaging.In this review,we firstly summarize the design of different types of NIR PLNPs for biosensing/bioimaging,such as transition metal ions-doped NIR PLNPs,lanthanide ions-doped NIR PLNPs,organic molecules-based NIR PLNPs,and semiconducting polymer self-assembled NIR PLNPs.Notably,organic molecules-based NIR PLNPs and semiconductor self-assembled NIR PLNPs,for the first time,were introduced to the review of PLNPs.Secondly,the effects of different types of charge carriers on NIR PersL and luminescence decay of NIR PLNPs are significantly emphasized so as to build up an in-depth understanding of their luminescence mechanism.It includes the regulation of valence band and conduction band of different host materials,alteration of defect types,depth and concentration changes caused by ion doping,effective radiation transitions and energy transfer generated by different luminescence centers.Given the design and potential of NIR PLNPs as long-lived luminescent materials,the current challenges and future perspective in this rapidly growing field are also discussed.
基金National Natural Science Foundation of China (Nos. 21771065 and 81630046)Natural Science Foundation of Guangdong Province, China (No. 2017A020215088)+2 种基金Science and Technology Planning Project of Guangdong Province, China (Nos. 2015B020233016 and 2014B020215003)Science and Technology Planning Project of Guangdong Province (Guangdong- Hong Kong Joint Innovation Project), China (No. 2014B050504009) Pearl River Nova Program of Guangzhou, Guangdong Province, China (No. 201806010189)Scientific and Technological Planning Project of Guangzhou, Guangdong Province, China (No. 201805010002).
文摘Cellular redox status presents broad implications with diverse physiological and pathological processes. Simultaneous detection of both the oxidative and reductive species of redox couples, especially the most representative pair glutathione/hydrogen peroxide (GSH/H2O2), is crucial to accurately map the cellular redox status. However, it still remains challenging to synchronously detect GSH/H2O2 in vivo due to lack of a reliable measuring tool. Herein, a ratiometric nanoprobe (UCNP-TB) possessing simultaneous delectability of GSH/H2O2 is established based on a multi-spectral upconverti ng nano phosphor (UCNP-OA) as the lumin esce nee res onance energy tran sfer (LRET) donor and two dye molecules as the acceptors, including a GSH-sensitive dye (TCG) and a H2O2-sensitive dye (BCH). With the as-prepared UCNP-TB, real-time and synchronous monitoring the variation of GSH and H2O2 in vitro and in living mice can be achieved using the ratio of the upcon versi on lumin esce nee (UCL) at 540 and 650 nm to that at 800 nm as the detecti on sign al, respectively, providi ng highly inhere nt reliability of the sensing results by self-calibrati on. Moreover, the nan oprobe is capable of mappi ng the redox status within the drug-resista nt tumor and the drug-induced hepatotoxic liver via ratiometric UCL imaging. Thus, this nan oprobe would provide a reliable tool to elucidate the redox state in vivo.
基金supported by the Science and Technology Cooperation Fund between Chinese and Australian Governments(No.2017YFE0132300)the Strategic Priority Research Program of the CAS(No.XDB20000000)+2 种基金the National Natural Science Foundation of China(Nos.11774345,12074379,21771185,21875250,and 11904365)the CAS/SAFEA International Partnership Program for Creative Research Teams,Natural Science Foundation of Fujian Province(No.202010037)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZR125).
文摘Inorganic luminescent nanocrystals(NCs)doped with main-group ns^(2)-metal ions have evoked tremendous interest in many technological fields owing to their superior optical properties.Herein,we report a new class of luminescent nanoprobes based on 5s2-metal Sb3+-doped CaS NCs that are excitable by using a near ultraviolet light-emitting diode.The optical properties and excited-state dynamics of Sb3+in CaS NCs are comprehensively surveyed through temperature-dependent steady-state and transient photoluminescence(PL)spectroscopies.Owing to the strong electron-phonon coupling of Sb^(3+)in CaS NCs,Sb3+ions experience a dynamic Jahn-Taller distortion on the excited state,which results in bright green PL of Sb3+with a broad emission band,a large Stokes shift,and a high PL quantum yield up to 17.3%.By taking advantage of the intense PL of Sb^(3+),we show in proof-of-concept experiments the application of biotinylated CaS:Sb^(3+)NCs as sensitive luminescent nanoprobes for biotin receptor-targeted cancer cell imaging and zebrafish imaging with a high imaging contrast.These findings provide fundamental insights into the excited-state dynamics of Sb^(3+)in CaS NCs,thus laying a foundation for future design of novel and versatile luminescent nanoprobes via main-group ns2-metal doping.
基金supported by the Strategic Priority Research Program of the CAS (No.XDB20000000)the National Natural Science Foundation of China (Nos.U1805252, 21771185,21804134, 51672272, and 21771178)the CAS/SAFEA International Partnership Program for Creative Research Teams, and Natural Science Foundation of Fujian Province (No.201710018).
文摘CuInS2 semiconductor nanocrystals (NCs) exhibit large absorption coefficient, size-dependent photoluminescence and low toxicity, making them excellent candidates in a variety of bioapplications. However, precise control of both their composition and morphology to improve the luminescent efficiency remains a great challenge via conventional direct synthesis. Herein, we present a novel low-temperature template synthesis of highly efficient luminescent CuInS2 nanoprobes from In2S3 NCs via a facile cation exchange strategy. The proposed strategy enables synthesis of a series of CuInS2 NCs with broad size tunability from 2.2 to 29.6 nm. Through rationally manipulating the stoichiometry of Cu/In, highly efficient luminescence of CuInS2 with the maximum quantum yield of 28.6% has been achieved, which is about one order of magnitude improvement relative to that of directly synthesized NCs. By virtue of the intense emission of CuInS2 nanoprobes, we exemplify their application in sensitive homogeneous biodetection for an important biomolecule of adenosine triphosphate (ATP) with the limit of detection down to 49.3 nM. Moreover, the CuInS2 nanoprobes are explored for ATP-targeted cancer cell imaging, thus revealing their great potentials in the field of cancer diagnosis and prognosis.
基金Project supported by the National Natural Science Foundation of China(61675067,51675174,61575062,61474042)the Scientific Research Fund of Hunan Provincial Education Department(16C0627,17B090)the Natural Science Foundation of Hunan Province,China(2016JJ2059,2018JJ3138)
文摘In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can be efficiently imbibed during the growing process and the absorbance presented a position dependence effect, which was supported by the upconversion spectra and the fluorescent image characterization. In addition, the concentration of the residual RhB in bean sprout can be efficiently traced by the synthesized probe based on the fluorescent resonant energy transfer. Finally, the relation between the excitation power, concentration and the ratio of yellow to green emission are discussed in detail. These results can be helpful in understanding the RhB dye molecules absorbance process in vegetable growth and provide an efficient way to trace the residual dyes in vivo plant.
基金the National Natural Science Foundation of China(Nos.81471779 and 31671003)Thousand Young Talents Program,the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(No.TP2014028)for their financial support
文摘Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications of Raman imaging. By adsorbing Raman molecules onto specific nanostructures such as noble metals, Raman signals can be significantly enhanced, termed surfaceenhanced Raman scattering(SERS). Recent years have witnessed great interest in the development of SERS nanoprobes for Raman imaging. Rationally designed SERS nanoprobes have greatly enhanced Raman signals by several orders of magnitude, thus showing great potential for biomedical applications.In this review we elaborate on recent progress in design strategies with emphasis on material properties,modifying factors, and structural parameters.
基金This research is supported by the National Natural Science Foundation of China(Nos.61331001,61627827,61805085 and 91539127)the Science and Technology Planning Project of Guangdong Province,China(Nos.2015B020233016,2014B020215003,2014A020215031,2014B050504009 and 2018A030310519)+2 种基金the Guangzhou Science and technology plan project(No.201904010321)the Distinguished Young Teacher Project in Higher Education of Guangdong,China(No.YQ2015049)the Science and Technology Program of Guangzhou(No.2019050001).
文摘The immense potential of carbon nanoprobes(CNPs)for using as contrast agents has propelled much recent research and development in the field of thermoacoustic(TA)molecular imaging,while the proper engineering and design of such materials with required high TA conversion efficiency is still a highly challenging task.In this work,we proposed a controllable strategy to amplify the TA conversion efficiency of the CNPs by constructing vacancy defect(VD)dipoles,and systematically demonstrated the amplification mechanism through theoretical and experimental investigations.First-principles calculation results indicate that,when a carbon atom is removed from the CNPs by chemical approach,owing to local electron density redistribution,the VDs are formed at the positions of the original carbon atoms and act as the structural origin of permanent electric dipoles with the dipole moment several orders higher than that of non-defect sites.Under pulsed microwave irradiation,the VD dipoles are polarized repeatedly and significantly contribute to the conversion efficiency from absorbed electromagnetic waves to ultrasound through enhanced dielectric relaxation losses.We experimentally synthesized graphene samples with different VD densities and VD types to demonstrate the efficiency of the proposed strategy,and results coincide well with the theoretical proposition.This work offers feasible guidance to the systematic development and rational design of new high-conversion-efficiency TA CNPs via VD engineering.
基金Project supported by the National Key R&D Program of China(2017YFA0205100)the National Natural Science Foundation of china(2193700321874027)。
文摘High-sensitivity detection of porphyrin in blood is very important for the early diagnosis and treatment of porphyria.Based on the advantages of longer luminescence lifetime and lower background interference,organic afterglow molecular porphyrin detection probes were developed,but these probes show poor water solubility and insufficient luminescence intensity.Herein,we present an afterglow nanoprobe(Eu-NP)for porphyria detection in whole blood.The luminescent substance(europium complex)and the organic vinyl co mpound reacted with singlet oxygen(^(1)O_(2))were selected for encapsulation in polystyrene spheres.Eu-NP can respond to^(1)O_(2)produced by porphyrins,and the detection signals can be obtained by the emission of the afterglow Eu^(3+)-emissive nanosensor.Eu-NP can achieve high-sensitivity detection of porphyrin,and the lowest detection limit reaches 0.29μmol/L.The porphyrin detection in whole blood samples is consistent with clinical diagnosis results.Compared with the organic afterglow molecule,the Eu-NPs constructed in this work show a higher signal-to-noise ratio and sensitivity of porphyria detection.
基金supported by STINT Joint China-Sweden Mobility Project(No.CH2017-7243)the Swedish Research Council(VR)(Nos.2019-02409 and 2020-05437)+2 种基金the China Scholarship Council(CSC),Carl Tryggers Stiftelse(No.CTS 19:379)Swedish Government strategic faculty grant in material science(SFO,MATLIU)in Advanced Functional Materials(AFM)(VR No.5.1-2015-5959)the Centre in Nano Science and technology at LiTH(CeNano),and LiU Cancer network at Linköping University.
文摘Mitophagy has a critical role in maintaining cellular homeostasis through acidic lysosomes engulfing excess or impaired mitochondria,thereby pH fluctuation is one of the most significant indicators for tracking mitophagy.Then such precise pH tracking demands the fluorogenic probe that has tailored contemporaneous features,including mitochondrial-specificity,excellent biocompatibility,wide pH-sensitive range of 8.0–4.0,and especially quantitative ability.However,available molecular probes cannot simultaneously meet all the requirements since it is extremely difficult to integrate multiple functionalities into a single molecule.To fully address this issue,we herein integrate two fluorogenic pH sensitive units,a mitochondria-specific block,cellpenetrating facilitator,and biocompatible segments into an elegant silica nano scaffold,which greatly ensures the applicability for real-time tracking of pH fluctuations in mitophagy.Most significantly,at a single wavelength excitation,the integrated pHsensitive units have spectra-distinguishable fluorescence towards alkaline and acidic pH in a broad range that covers mitochondrial and lysosomal pH,thus enabling a ratiometric analysis of pH variations during the whole mitophagy.This work also provides constructive insights into the fabrication of advanced fluorescent nanoprobes for diverse biomedical applications.
基金National Natural Science Foundation of China(Nos.U1704161,U1504203,21601158)Zhengzhou University(No.32210431)for the financial supports。
文摘A ratiometric fluorescent hybrid nanoprobe CDs-1 for arginine(Arg),exhibiting high sensitivity(the limit of detection,LOD,being 6.5×10^-8 mol/L) and excellent selectivity and anti-interference ability,was fabricated through fluorescence resonance energy transfer(FRET) and the electrostatic attraction between positively-charged hemicyanine molecules and negatively-charged carbon dots(CDs).Arg can be quantitatively detected in the concentration range from 6.0×10^-5 mol/L to 2.7×10^-4 mol/L.Further,due to its ability to target mitochondrion and low cytotoxicity,intracellular Arg was succes s fully tracked through ratiometric fluorescence imaging.
基金supported by 973 Program (No. 2013CB933800) National Natural Science Foundation of China (Nos. 21390411, 21535004, 21422505, 21375081)Natural Science Foundation for Distinguished Young Scholars of Shandong Province (No. JQ201503)
文摘Ascorbic acid(AA) serves as a key coenzyme in many metabolic pathways. Enough daily AA supplements from different dietary sources are the only way for human to maintain their AA levels in body.Determination of AA content in different foods guides to build healthy diet, which is of great biomedical significance. Hence, developing a highly selective and instantaneous fluorescent nanoprobe for the detection of AA in biological samples is highly needed. Here we present a novel turn-on fluorescent nanoprobe using lanthanide-doped upconversion nanoparticles(UCNPs) and cobalt oxyhydroxide(Co OOH) nanoflakes for monitoring AA in fruit samples. In this nanosystem, the UCNPs can be adsorbed onto the Co OOH nanoflakes, leading to a remarkable fluorescence decrease through Fo?rster resonance energy transfer. Furthermore, the AA could trigger the disassembly of the Co OOH to liberate the upconverted fluorescence. The UCNPs-based nanoprobe can provide an effective platform for highly selective and rapid detection of AA in biological samples.
