Endosulfan, an organochlorine pesticide, is known for its toxicity and ability to accumulate in the environment. In India endosulfan was banned only in 2011 and hence toxic residues are still persistent in the environ...Endosulfan, an organochlorine pesticide, is known for its toxicity and ability to accumulate in the environment. In India endosulfan was banned only in 2011 and hence toxic residues are still persistent in the environment. The abilities of three plant species Chittaratha (Alpinia calcarata), Tulsi (Ocimum sanctum), and Lemongrass (Cymbopogon citratus) to remove endosulfan from soil in the absence and presence of zerovalent iron nanoparticles (nZVIs) (1000 mg/Kg of soil), i.e., by phytoremediation and nano-phytoremediation, were determined. Extracted soil samples from the experimental plot were analyzed using Gas Chromatograph with Electron Capture Detector (GC-ECD) and final dehalogenated product was confirmed by Mass Spectrometer (MS). A. calcarata had the best efficiency compared to the other two plant species and the efficiency decreased in the order A. calcarata > O. sanctum> C. citrates. The initial endosulfan removal rate was high (82% was removed within 7 days) when nano phytoremediation experiments were conducted with A. calcarata but then gradually decreased, probably because the activity of nZVI decreased over time. The nZVI endosulfan degradation mechanism appears to involve hydrogenolysis and sequential dehalogenation which was confirmed by GC-MS analysis. Only small amounts of endosulfan were accumulated in the plants because the added nZVIs might have promoted the reductive dechlorination of endosulfan.展开更多
Superparamagnetic iron oxide nanoparticles(SPIONs)have immeasurable potentials in many fields such as nanobiotechnology and biomedical engineering because of their superparamagnetic properties and small particle size....Superparamagnetic iron oxide nanoparticles(SPIONs)have immeasurable potentials in many fields such as nanobiotechnology and biomedical engineering because of their superparamagnetic properties and small particle size.This review introduces the methods for SPIONs synthesis,including co-precipitation,thermal decomposition,microemulsion and hydrothermal reaction,and surface modification of SPIONs with organometallic and inorganic metals,surface modification for targeted drug delivery,and the use of SPIONs as a contrast agent.In addition,this article also provides an overview of recent progress in SPIONs for the treatment of glioma,lung cancer and breast cancer.展开更多
Cell labeling with magnetic iron oxide nanoparticles(IONPs)is increasingly a routine approach in the cellbased cancer treatment.However,cell labeling with magnetic IONPs and their leading effects on the biological pro...Cell labeling with magnetic iron oxide nanoparticles(IONPs)is increasingly a routine approach in the cellbased cancer treatment.However,cell labeling with magnetic IONPs and their leading effects on the biological properties of human lung carcinoma cells remain scarcely reported.Therefore,in the present study the magnetic c-Fe2O3nanoparticles(MNPs)were firstly synthesized and surface-modified with cationic poly-L-lysine(PLL)to construct the PLL-MNPs,which were then used to magnetically label human A549 lung cancer cells.Cell viability and proliferation were evaluated with propidium iodide/fluorescein diacetate double staining and standard 3-(4,5-dimethylthiazol-2-diphenyl-tetrazolium)bromide assay,and the cytoskeleton was immunocytochemically stained.The cell cycle of the PLL-MNPlabeled A549 lung cancer cells was analyzed using flow cytometry.Apoptotic cells were fluorescently analyzed with nuclear-specific staining after the PLL-MNP labeling.The results showed that the constructed PLL-MNPs efficiently magnetically labeled A549 lung cancer cells and that,at low concentrations,labeling did not affect cellular viability,proliferation capability,cell cycle,and apoptosis.Furthermore,the cytoskeleton in the treated cells was detected intact in comparison with the untreated counterparts.However,the results also showed that at high concentration(400 lg m L-1),the PLL-MNPs would slightly impair cell viability,proliferation,cell cycle,and apoptosis and disrupt the cytoskeleton in the treated A549 lung cancer cells.Therefore,the present results indicated that the PLL-MNPs at adequate concentrations can be efficiently used for labeling A549 lung cancer cells and could be considered as a feasible approach for magnetic targeted anti-cancer drug/gene delivery,targeted diagnosis,and therapy in lung cancer treatment.展开更多
Due to their very small size,nanoparticles can interact with all cells in the central nervous system.One of the most promising nanoparticle subgroups are very small superparamagnetic iron oxide nanoparticles(VSOP)that...Due to their very small size,nanoparticles can interact with all cells in the central nervous system.One of the most promising nanoparticle subgroups are very small superparamagnetic iron oxide nanoparticles(VSOP)that are citrate coated for electrostatic stabilization.To determine their influence on murine blood-derived monocytes,which easily enter the injured central nervous system,we applied VSOP and carboxydextran-coated superparamagnetic iron oxide nanoparticles(Resovist).We assessed their impact on the viability,cytokine,and chemokine secretion,as well as iron uptake of murine blood-derived monocytes.We found that(1)the monocytes accumulated VSOP and Resovist,(2)this uptake seemed to be nanoparticle-and time-dependent,(3)the decrease of monocytes viability was treatment-related,(4)VSOP and Resovist incubation did not alter cytokine homeostasis,and(5)overall a 6-hour treatment with 0.75 mM VSOP-R1 was probably sufficient to effectively label monocytes for future experiments.Since homeostasis is not altered,it is safe to label blood-derived monocles with VSOP.VSOP labeled monocytes can be used to study injured central nervous system sites further,for example with drug-carrying VSOP.展开更多
This work aims to establish comparisons between two models used for the performance of heat exchangers. The chosen system, in this case, consists of a heat exchanger used in automotive radiators flat finned tube type....This work aims to establish comparisons between two models used for the performance of heat exchangers. The chosen system, in this case, consists of a heat exchanger used in automotive radiators flat finned tube type. Water and ethylene glycol compound as base fluid and volume fractions of iron oxide nanoparticles (Fe<sub>3</sub>O<sub>4</sub>) are used as a refrigerant. The quantities determined in this work are the nanofluid exit temperature, the air exit temperature, the absolute error between the models for heat transfer rate, and Effectiveness. The quantities that constitute parameters, independent variables, are the airflow, represented by the Reynolds number, and the iron oxide volume fraction. Ethylene Glycol 50% compound has slightly better thermal performance than pure water and reduces the reactive effect of water on the environment, increasing the average life of the equipment. The absolute relative error between the models is less than 20% and presents maximum values with the increase of the nanoparticle volume fraction and growth in the Reynolds number for the air.展开更多
Antibacterial activity of iron oxide nanoparticles, an employing B. aegyptiaca oil (L.) Del., was used as natural stabilizer by modifying a co-precipitation method. In this work, we chose B. aegyptiaca oil as the new ...Antibacterial activity of iron oxide nanoparticles, an employing B. aegyptiaca oil (L.) Del., was used as natural stabilizer by modifying a co-precipitation method. In this work, we chose B. aegyptiaca oil as the new surfactant coating agent, and synthesized B. aegyptiaca oil coating with iron oxide nanoparticles which were characterized with a variety of methods, including Gas Chromatography (GC) to determine the fatty acids composition of the seeds oil, Fourier Transform-Infrared Spectroscopy (FTIR), Transmission Electron Microscopy (TEM) equipped with Energy Dispersive Spectroscopy (EDS), X-ray Powder Diffractometer (XRD) and Vibrating Sample Magnetometer (VSM). In antibacterial studies, disk diffusion susceptibility test was used to measure efficacy of iron oxide nanoparticles against Gram-positive bacteria Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis) and Gram-negative bacteria Escherichia coli (E. coli) in terms of zone inhibition. The B. aegyptiaca coated on the surface of iron oxide nanoparticles;its particle size was found to be nanoscale below 50 nm, and the magnetization (<sup><sup></sup>δ</sup>s) was 16.975 emu g<sup>-1</sup>. Antibacterial activity was measured. Efficacy of iron oxide nanoparticles against bacterial strains was found in Escherichia coli (E. coli). All these findings suggest that the nanoparticles synthesized from B. aegyptiaca oil may be a promising reagent for a wide variety of applications in biological fields as well as in nanomedicine.展开更多
A green and convenient pathway of preparing iron nanoparticles(FeNPs)with pomegranate leaf(PG)extract for highly effective removal of malachite green(MG)was proposed under ambient conditions.The materials were charact...A green and convenient pathway of preparing iron nanoparticles(FeNPs)with pomegranate leaf(PG)extract for highly effective removal of malachite green(MG)was proposed under ambient conditions.The materials were characterized by scanning electron microscope(SEM),X-ray energy-dispersive spectrometer(EDS),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)techniques.The results show that their surfaces are capped and stabilized by PG extract with amorphous nature and without any detection of zero-valent iron.The size and surface valence state of FeNPs are the key factors that affect the MG removal efficiency.As the reagent volume ratio of PG extract to FeCl_(3) increases greater than 1,the cross-linked FeNPs become more obvious,having a homogeneous distribution with the size range from 30 to 40 nm,and show an increasing ratio ofFe(Ⅱ)/Fe(Ⅲ),which is in proportion to the degradation efficiency of MG,reaching higher than 95%in only 2 min by using 50 mg Fe/L FeNPs and 200 mg/L MG.展开更多
Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast agents.Especi...Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast agents.Especially when the particle size is less than 10 nm,it has strong diffusion ability and deep penetration distance in tumor tissue.Substitution doping can significantly enhance the T_(1)contrast effect of nanoparticles by regulating the surface exposed atoms.However,the nucleation and growth processes of multi-component synthesis systems are complex and difficult to be accurately controlled,leading to great challenges in the synthesis of ultra-small-sized nanoparticles with different components and sizes.Here,extremely smallsized superparamagnetic gadolinium-doped iron oxide nanoparticles(GdIONPs,Gd_(x)Fe_(3-x)O_(4) NPs) with adjustable doping amount and controllable size in the range of 3.5-7.5 nm were synthesized by thermal decomposition.Then,as-synthesized GdIONPs were surface modified with a highly water-soluble and biocompatible carboxyl-polyethylene glycol-phosphoric acid ligand with high binding affinity.Gd_(0.65)Fe_(2.35)O_(4) NPs exhibited very high r_(1) relaxivity of 10.6 mmol^(-1)·L·s^(-1) in terms of all metal concentrations and 49.0 mmol^(-1)·L·s^(-1) in terms of gadolinium alone,respectively,3 and 14 times higher than clinical T_(1) contrast agents(Gd-DTPA).GdIONPs can continuously obtain high resolution images of blood vessels,and can be used as an efficient and multifunctional contrast agent for MR T_(1)imaging.This stable and efficient doping strategy provides an easy and effective method to individually optimize the magnetic properties of complex oxides and their relaxation effects for a variety of biomedical applications.展开更多
The preparation of γ-Fe<sub>2</sub>O<sub>3</sub>/Gd<sub>2</sub>O<sub>3</sub> nanocomposite for possible use in magnetic hyperthermia application was done by ball millin...The preparation of γ-Fe<sub>2</sub>O<sub>3</sub>/Gd<sub>2</sub>O<sub>3</sub> nanocomposite for possible use in magnetic hyperthermia application was done by ball milling technique. The nanocomposite was characterized by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The heating efficiency and the effect of milling time (5 h and 30 h) on the structural and magnetic properties of the nanocomposite were reported. XRD analysis confirms the formation of the nanocomposite, while magnetization measurements show that the milled sample present hysteresis with low coercivity and remanence. The specific absorption rate (SAR) under an alternating magnetic field is investigated as a function of the milling time. A mean heating efficiency of 68 W/g and 28.7 W/g are obtained for 5 h and 30 h milling times respectively at 332 kHz and 170 Oe. The results showed that the obtained nanocomposite for 5 h milling time is a promising candidate for magnetic hyperthermia due to his properties which show an interesting magnetic behavior and high specific absorption rate.展开更多
The undesirable shuttle effect and sluggish redox kinetics of polysulfides seriously result in low sulfur utilization and poor capacity retention.Here,an integrated strategy is proposed by rational designing multifunc...The undesirable shuttle effect and sluggish redox kinetics of polysulfides seriously result in low sulfur utilization and poor capacity retention.Here,an integrated strategy is proposed by rational designing multifunctional architecture to manipulate the redox kinetics of polysulfides,specifically,by employing iron atoms(Fe-As)and iron-species nanoparticles(Fe-NPs)co-embedded nitrogen-doped carbon nanotube(Fe-NCNT)as catalyst and host for sulfur.The synergistic cooperation of Fe-As and Fe-NPs provides efficient active sites to facilitate the diffusion,strengthen the affinities,and promote the conversion reactions for polysulfides.Furthermore,the NCNT not only offers practical Li+transport pathways but also immobilize the polysulfides effectively.Benefiting from these merits,the Fe-NCNT/S electrodes exhibit high initial specific capacity of 1502.6 mAh/g at 0.1 C,outstanding rate performance(830 mAh/g at 2 C),and good cycling performance(597.8 mAh/g after 500 cycles with an ultralow capacity fading rate of 0.069%per cycle).This work features the distinct interaction of iron atom-nanoparticles on facilitating immobilization-diffusion-transformation process of polysulfides,and it also expected to pave the way for the application in practical Li-S batteries.展开更多
Despite advances in diagnostic and therapeutic technologies for cardiovascular diseases(CVDs),it remains a leading cause of mortality and morbidity worldwide.This underscores the urgency for innovative approaches aimi...Despite advances in diagnostic and therapeutic technologies for cardiovascular diseases(CVDs),it remains a leading cause of mortality and morbidity worldwide.This underscores the urgency for innovative approaches aiming at early and precise detection and treatment of CVDs to reduce the disease burden.Iron oxide nanoparticles(IONPs),with their unique magnetism and bioproperties,have shown great potential in this regard.In this review,we will begin with a brief overview of the synthesis and properties of IONPs.We will then focus on the latest applications of IONPs in CVDs,including diagnosis and treatment.The use of IONPs in the integration of diagnosis and treatment for CVDs is a promising field,and will be addressed in a separate section.The translational potential and challenges of IONPs will also be discussed.In conclusion,ongoing research and development of IONP-based strategies are highly likely to address current challenges effectively,and offer more personalized and efficient options for the diagnosis and treatment of CVDs.展开更多
Iron oxide nanoparticles(IONPs)modified with functional proteins hold great promise in the biomedical field.However,conventional protein modification strategies,such as adsorption and covalent coupling,are either unst...Iron oxide nanoparticles(IONPs)modified with functional proteins hold great promise in the biomedical field.However,conventional protein modification strategies,such as adsorption and covalent coupling,are either unstable or nonspecific,or may result in the changes of protein structure and ultimately the loss of protein activity.Modification of active proteins on small-sized IONPs with a particle size of less than 30 nm is especially difficult due to their high surface energy.Herein,we developed a universal modifica-tion method based on Spy chemistry for rapid and stable protein immobilization on small-sized IONPs,which only requires the presence of active groups on the surface of nanoparticles that can couple with SpyCatcher.In short,the SpyCatcher peptides were first coated on the surface of IONPs by cross-linking with activated groups,and then the SpyTag peptide fused with a model protein(enhanced green fluo-rescent protein,EGFP)was engineered(SpyTag-EGFP)and directly coupled to SpyCatcher-modified IONPs by self-assembly,which is spontaneous and robust while avoiding the effect of chemical reactions on functional protein activity.The obtained EGFP-functionalized IONPs exhibited enhanced and stable green fluorescence and improved magnetic properties.In addition,the cell internalization efficiency of EGFP-functionalized IONPs was significantly increased as compared to unmodified IONPs,providing an ideal solution for efficient cell labeling and tracking.In conclusion,here we report a rapid and easy strategy for EGFP immobilization on IONPs based on Spy chemistry,which could be further adapted to other functional proteins in the future.SpyCatcher-modified IONPs and SpyTag-X(arbitrary functional fusion proteins)hold great potential to be applied as a versatile platform for protein immobilization on IONPs and enable its multifunctional application in the future.展开更多
Sustainable metal-air batteries demand high-efficiency,environmentally-friendly,and non-precious metal-based electrocatalysts with bifunctionality for both the oxygen reduction reaction(ORR)and oxygen evolution reacti...Sustainable metal-air batteries demand high-efficiency,environmentally-friendly,and non-precious metal-based electrocatalysts with bifunctionality for both the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).In this research,novel functional carbon nanotubes with multi-active sites including well-dispersed single-atom iron throughout the walls and encapsulated ultrafine iron nanoparticles were synthesized as an electrocatalyst(FeNP@Fe-N-C)through one-step pyrolysis of metal-organic frameworks.High-resolution synchrotron powder X-ray diffraction and X-ray absorption spectroscopy were applied to characterize the unique structure of the electrocatalyst.In comparison to the commercial Pt/C and Ru O_(2)electrodes,the newly prepared FeNP@Fe-N-C presented a superb bifunctional performance with its narrow potential difference(Egap)of 0.73 V,which is ascribed to the metallic Fe nanoparticles that boosts the adsorption and activation of oxygen on the active sites with an enhanced O_(2)adsorption capacity of 7.88 cm^(3)g^(-1)and synergistically functionalizes the iron atoms dispersed on the nanotubes.A rechargeable zinc-air battery based on FeNP@Fe-N-C exhibited a superior open-circuit voltage(1.45 V),power density(106.5 m W cm^(-2)),and stable cycling performance.The green technique developed in this work for the fabrication of functional nanotubes raises the prospect of making more efficient electrocatalysts for sustainable energy cells.展开更多
CO_(2)electroreduction reaction(CO_(2)RR),combined with solid oxide electrolysis cells(SOECs),is a feasible technology for the storage of renewable electric energy,while its development is limited by the catalytic act...CO_(2)electroreduction reaction(CO_(2)RR),combined with solid oxide electrolysis cells(SOECs),is a feasible technology for the storage of renewable electric energy,while its development is limited by the catalytic activity and stability on cathodes.Here,a novel garnet oxide(Gd_(3)Fe_(5)O_(12))cathode is designed,where the garnet oxide is converted to perovskite oxide and iron via in situ electrochemical phase transition during CO_(2)electroreduction,resulting in high activity with Faradaic efficiency close to 100%and great stability over 1000 h galvanostatic test.A variety of experimental characterizations and density functional theory calculations indicate that in situ exsolved Fe clusters can effectively enhance the adsorption energies of intermediates and lowering the CO_(2)dissociation barriers.Microkinetic modelling confirms that CO_(2)RR goes through a dissociative adsorption mechanism and the electronic transfer for CO_(2)dissociation is the rate-determining step.展开更多
Anaerobic digestion is widely used in the treatment of industrial wastewater,excess activated sludge,municipal waste,crop straw and livestock manure,with the functions of environmental protection and energy recovery. ...Anaerobic digestion is widely used in the treatment of industrial wastewater,excess activated sludge,municipal waste,crop straw and livestock manure,with the functions of environmental protection and energy recovery. This review summarizes and evaluates the present knowledge of effects of different states of Fe( ZVI,Fe( II),Fe( III)) on hydrogen and methane production in anaerobic digestion process. The potential promotion effects of iron oxides nanoparticles( IONPs),especially magnetite nanoparticles on anaerobic digestion are also mentioned. Fe plays important role in transporting electron,stimulating bacterial growth and increasing hydrogen and methane production rate by promoting enzyme activity. Adding Fe with different morphologies and valence states in anaerobic digestion to increase biogas( hydrogen and methane) production and enhance organic matter degradation simultaneously,which has attracted many scientists' attention in recent years. Rapid progress in this area has been made over the last few years,since Fe is essential to the fermentative hydrogen and methane production,while few is known about how Fe affects the fermentative biogas production. This review is significant to maintain the stable operation of the biogas project.展开更多
Despite being a common therapy for hepatocellular carcinoma(HCC),insufficient thermal ablation can leave behind tumor residues that can cause recurrence.This is believed to augment M2 inflammatory macrophages that usu...Despite being a common therapy for hepatocellular carcinoma(HCC),insufficient thermal ablation can leave behind tumor residues that can cause recurrence.This is believed to augment M2 inflammatory macrophages that usually play a pro-tumorigenic role.To address this problem,we designed D-mannose-chelated iron oxide nanoparticles(man-IONPs) to polarize M2-like macrophages into the antitumor Ml phenotype.In vitro and in vivo experiments demonstrated that man-IONPs specifically targeted M2-like macrophages and accumulated in peri-ablation zones after macrophage infiltration was augmented under insufficient microwave ablation(MWA).The nanoparticles simultaneously induced polarization of pro-tumorigenic M2 macrophages into antitumor M1 phenotypes,enabling the transformation of the immunosuppressive microenvironment into an immunoactivating one.Post-MWA macrophage polarization exerted robust inhibitory effects on HCC progression in a well-established orthotopic liver cancer mouse model.Thus,combining thermal ablation with man-IONPs can salvage residual tumors after insufficient MWA.These results have strong potential for clinical translation.展开更多
Breast cancer bone metastasis poses significant challenge for therapeutic strategies.Inside the metastatic environment,osteoclasts and tumor cells interact synergistically to promote cancer progression.In this study,t...Breast cancer bone metastasis poses significant challenge for therapeutic strategies.Inside the metastatic environment,osteoclasts and tumor cells interact synergistically to promote cancer progression.In this study,the proprotein convertase furin is targeted due to its critical roles in both tumor cell invasion and osteoclast function.Importantly,the furin inhibitor is specifically delivered by bone targeting superparamagnetic iron oxide(SPIO)nanoparticles.Our in vitro and in vivo data demonstrate that this system can effectively inhibit both osteoclastic bone resorption and breast cancer invastion,leading to alleviated osteolysis.Therefore,the bone targeting&furin inhibition nanoparticle system is a promising therapeutic and diagnostic strategy for breast cancer bone metastasis.展开更多
Dextran-coated superparamagnetic iron oxide nanoparticles(Dex-SPIONs)are excellent magnetic resonance imaging contrast agents for disease diagnosis and therapy.They can be delivered to target tissues mainly though vas...Dextran-coated superparamagnetic iron oxide nanoparticles(Dex-SPIONs)are excellent magnetic resonance imaging contrast agents for disease diagnosis and therapy.They can be delivered to target tissues mainly though vascular endothelium cells,which are major targets of oxidative stress.In cardiovascular cells,autophagy serves primarily on a pro-survival approach that protects the cells from oxidative stress even some autophagy inducers have been developed for adjuvant therapy of cardiovascular disorders.Our study demonstrated that the nanoparticles could be taken up by human umbilical vein endothelial cells(HUVECs)without causing obvious cytotoxicity but triggering autophagy.Furthermore,our results revealed that Dex-SPIONs could enhance HUVECs survival and reverse the reduction of nitric oxide secretion under the condition of H2O2 damage.However,these effects could be diminished by the autophagy inhibitor.In particular,we discovered that Dex-SPIONs evoked autophagy in HUVECs by reducing the phosphorylation of PRAS40,an upstream regulator of autophagy initiation.These results suggested that Dex-SPIONs functions as an autophagic-related antioxidant in HUVECs which may be utilized as an adjuvant therapy to cardiovascular disease associated with oxidative stress.展开更多
Iron oxide nanoparticle(IONP)with unique magnetic property and high biocompatibility have been widely used as magnetic resonance imaging(MRI)contrast agent(CA)for long time.However,a review which comprehensively summa...Iron oxide nanoparticle(IONP)with unique magnetic property and high biocompatibility have been widely used as magnetic resonance imaging(MRI)contrast agent(CA)for long time.However,a review which comprehensively summarizes the recent development of IONP as traditional T_(2) CA and its new application for different modality of MRI,such as T_(1) imaging,simultaneous T_(2)/T_(1) or MRI/other imaging modality,and as environment responsive CA is rare.This review starts with an investigation of direction on the development of high-performance MRI CA in both T_(2) and T_(1) modal based on quantum mechanical outer sphere and Solomon-Bloembergen-Morgan(SBM)theory.Recent rational attempts to increase the MRI contrast of IONP by adjusting the key parameters,including magnetization,size,effective radius,inhomogeneity of surrounding generated magnetic field,crystal phase,coordination number of water,electronic relaxation time,and surface modification are summarized.Besides the strategies to improve r2 or r1 values,strategies to increase the in vivo contrast efficiency of IONP have been reviewed from three different aspects,those are introducing second imaging modality to increase the imaging accuracy,endowing IONP with environment response capacity to elevate the signal difference between lesion and normal tissue,and optimizing the interface structure to improve the accumulation amount of IONP in lesion.This detailed review provides a deep understanding of recent researches on the development of high-performance IONP based MRI CAs.It is hoped to trigger deep thinking for design of next generation MRI CAs for early and accurate diagnosis.展开更多
文摘Endosulfan, an organochlorine pesticide, is known for its toxicity and ability to accumulate in the environment. In India endosulfan was banned only in 2011 and hence toxic residues are still persistent in the environment. The abilities of three plant species Chittaratha (Alpinia calcarata), Tulsi (Ocimum sanctum), and Lemongrass (Cymbopogon citratus) to remove endosulfan from soil in the absence and presence of zerovalent iron nanoparticles (nZVIs) (1000 mg/Kg of soil), i.e., by phytoremediation and nano-phytoremediation, were determined. Extracted soil samples from the experimental plot were analyzed using Gas Chromatograph with Electron Capture Detector (GC-ECD) and final dehalogenated product was confirmed by Mass Spectrometer (MS). A. calcarata had the best efficiency compared to the other two plant species and the efficiency decreased in the order A. calcarata > O. sanctum> C. citrates. The initial endosulfan removal rate was high (82% was removed within 7 days) when nano phytoremediation experiments were conducted with A. calcarata but then gradually decreased, probably because the activity of nZVI decreased over time. The nZVI endosulfan degradation mechanism appears to involve hydrogenolysis and sequential dehalogenation which was confirmed by GC-MS analysis. Only small amounts of endosulfan were accumulated in the plants because the added nZVIs might have promoted the reductive dechlorination of endosulfan.
基金Supported by National Natural Science Foundation of China(32060228)。
文摘Superparamagnetic iron oxide nanoparticles(SPIONs)have immeasurable potentials in many fields such as nanobiotechnology and biomedical engineering because of their superparamagnetic properties and small particle size.This review introduces the methods for SPIONs synthesis,including co-precipitation,thermal decomposition,microemulsion and hydrothermal reaction,and surface modification of SPIONs with organometallic and inorganic metals,surface modification for targeted drug delivery,and the use of SPIONs as a contrast agent.In addition,this article also provides an overview of recent progress in SPIONs for the treatment of glioma,lung cancer and breast cancer.
基金supported by the National Natural Science Foundation of China(No.314 008 55)the Technological Innovation Incubator Program from Henan University of Technology(No.201 518)the Introduced Postdoctoral Talents of Henan University of Technology(No.150 199)
文摘Cell labeling with magnetic iron oxide nanoparticles(IONPs)is increasingly a routine approach in the cellbased cancer treatment.However,cell labeling with magnetic IONPs and their leading effects on the biological properties of human lung carcinoma cells remain scarcely reported.Therefore,in the present study the magnetic c-Fe2O3nanoparticles(MNPs)were firstly synthesized and surface-modified with cationic poly-L-lysine(PLL)to construct the PLL-MNPs,which were then used to magnetically label human A549 lung cancer cells.Cell viability and proliferation were evaluated with propidium iodide/fluorescein diacetate double staining and standard 3-(4,5-dimethylthiazol-2-diphenyl-tetrazolium)bromide assay,and the cytoskeleton was immunocytochemically stained.The cell cycle of the PLL-MNPlabeled A549 lung cancer cells was analyzed using flow cytometry.Apoptotic cells were fluorescently analyzed with nuclear-specific staining after the PLL-MNP labeling.The results showed that the constructed PLL-MNPs efficiently magnetically labeled A549 lung cancer cells and that,at low concentrations,labeling did not affect cellular viability,proliferation capability,cell cycle,and apoptosis.Furthermore,the cytoskeleton in the treated cells was detected intact in comparison with the untreated counterparts.However,the results also showed that at high concentration(400 lg m L-1),the PLL-MNPs would slightly impair cell viability,proliferation,cell cycle,and apoptosis and disrupt the cytoskeleton in the treated A549 lung cancer cells.Therefore,the present results indicated that the PLL-MNPs at adequate concentrations can be efficiently used for labeling A549 lung cancer cells and could be considered as a feasible approach for magnetic targeted anti-cancer drug/gene delivery,targeted diagnosis,and therapy in lung cancer treatment.
基金supported by Deutsche Forschungsgemeinschaft(DFG)grant Klinische Forschergruppe(KFO)213(to JG).
文摘Due to their very small size,nanoparticles can interact with all cells in the central nervous system.One of the most promising nanoparticle subgroups are very small superparamagnetic iron oxide nanoparticles(VSOP)that are citrate coated for electrostatic stabilization.To determine their influence on murine blood-derived monocytes,which easily enter the injured central nervous system,we applied VSOP and carboxydextran-coated superparamagnetic iron oxide nanoparticles(Resovist).We assessed their impact on the viability,cytokine,and chemokine secretion,as well as iron uptake of murine blood-derived monocytes.We found that(1)the monocytes accumulated VSOP and Resovist,(2)this uptake seemed to be nanoparticle-and time-dependent,(3)the decrease of monocytes viability was treatment-related,(4)VSOP and Resovist incubation did not alter cytokine homeostasis,and(5)overall a 6-hour treatment with 0.75 mM VSOP-R1 was probably sufficient to effectively label monocytes for future experiments.Since homeostasis is not altered,it is safe to label blood-derived monocles with VSOP.VSOP labeled monocytes can be used to study injured central nervous system sites further,for example with drug-carrying VSOP.
文摘This work aims to establish comparisons between two models used for the performance of heat exchangers. The chosen system, in this case, consists of a heat exchanger used in automotive radiators flat finned tube type. Water and ethylene glycol compound as base fluid and volume fractions of iron oxide nanoparticles (Fe<sub>3</sub>O<sub>4</sub>) are used as a refrigerant. The quantities determined in this work are the nanofluid exit temperature, the air exit temperature, the absolute error between the models for heat transfer rate, and Effectiveness. The quantities that constitute parameters, independent variables, are the airflow, represented by the Reynolds number, and the iron oxide volume fraction. Ethylene Glycol 50% compound has slightly better thermal performance than pure water and reduces the reactive effect of water on the environment, increasing the average life of the equipment. The absolute relative error between the models is less than 20% and presents maximum values with the increase of the nanoparticle volume fraction and growth in the Reynolds number for the air.
文摘Antibacterial activity of iron oxide nanoparticles, an employing B. aegyptiaca oil (L.) Del., was used as natural stabilizer by modifying a co-precipitation method. In this work, we chose B. aegyptiaca oil as the new surfactant coating agent, and synthesized B. aegyptiaca oil coating with iron oxide nanoparticles which were characterized with a variety of methods, including Gas Chromatography (GC) to determine the fatty acids composition of the seeds oil, Fourier Transform-Infrared Spectroscopy (FTIR), Transmission Electron Microscopy (TEM) equipped with Energy Dispersive Spectroscopy (EDS), X-ray Powder Diffractometer (XRD) and Vibrating Sample Magnetometer (VSM). In antibacterial studies, disk diffusion susceptibility test was used to measure efficacy of iron oxide nanoparticles against Gram-positive bacteria Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis) and Gram-negative bacteria Escherichia coli (E. coli) in terms of zone inhibition. The B. aegyptiaca coated on the surface of iron oxide nanoparticles;its particle size was found to be nanoscale below 50 nm, and the magnetization (<sup><sup></sup>δ</sup>s) was 16.975 emu g<sup>-1</sup>. Antibacterial activity was measured. Efficacy of iron oxide nanoparticles against bacterial strains was found in Escherichia coli (E. coli). All these findings suggest that the nanoparticles synthesized from B. aegyptiaca oil may be a promising reagent for a wide variety of applications in biological fields as well as in nanomedicine.
基金the National Natural Science Foundation of China(No.21407050)the Excellent Young and Middle-aged Science and Technology Innovation Team Plan of Hubei Colleges(No.T201824)。
文摘A green and convenient pathway of preparing iron nanoparticles(FeNPs)with pomegranate leaf(PG)extract for highly effective removal of malachite green(MG)was proposed under ambient conditions.The materials were characterized by scanning electron microscope(SEM),X-ray energy-dispersive spectrometer(EDS),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)techniques.The results show that their surfaces are capped and stabilized by PG extract with amorphous nature and without any detection of zero-valent iron.The size and surface valence state of FeNPs are the key factors that affect the MG removal efficiency.As the reagent volume ratio of PG extract to FeCl_(3) increases greater than 1,the cross-linked FeNPs become more obvious,having a homogeneous distribution with the size range from 30 to 40 nm,and show an increasing ratio ofFe(Ⅱ)/Fe(Ⅲ),which is in proportion to the degradation efficiency of MG,reaching higher than 95%in only 2 min by using 50 mg Fe/L FeNPs and 200 mg/L MG.
基金financially supported by the Project of High-level Teachers in Beijing Municipal Universities in the Period of 13th Five-Year Plan (No.CIT&TCD201804025)Beijing Municipal Education Commission (No.KM201910011009)the Graduate Student Scientific Research Ability Promotion of BTBU。
文摘Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast agents.Especially when the particle size is less than 10 nm,it has strong diffusion ability and deep penetration distance in tumor tissue.Substitution doping can significantly enhance the T_(1)contrast effect of nanoparticles by regulating the surface exposed atoms.However,the nucleation and growth processes of multi-component synthesis systems are complex and difficult to be accurately controlled,leading to great challenges in the synthesis of ultra-small-sized nanoparticles with different components and sizes.Here,extremely smallsized superparamagnetic gadolinium-doped iron oxide nanoparticles(GdIONPs,Gd_(x)Fe_(3-x)O_(4) NPs) with adjustable doping amount and controllable size in the range of 3.5-7.5 nm were synthesized by thermal decomposition.Then,as-synthesized GdIONPs were surface modified with a highly water-soluble and biocompatible carboxyl-polyethylene glycol-phosphoric acid ligand with high binding affinity.Gd_(0.65)Fe_(2.35)O_(4) NPs exhibited very high r_(1) relaxivity of 10.6 mmol^(-1)·L·s^(-1) in terms of all metal concentrations and 49.0 mmol^(-1)·L·s^(-1) in terms of gadolinium alone,respectively,3 and 14 times higher than clinical T_(1) contrast agents(Gd-DTPA).GdIONPs can continuously obtain high resolution images of blood vessels,and can be used as an efficient and multifunctional contrast agent for MR T_(1)imaging.This stable and efficient doping strategy provides an easy and effective method to individually optimize the magnetic properties of complex oxides and their relaxation effects for a variety of biomedical applications.
文摘The preparation of γ-Fe<sub>2</sub>O<sub>3</sub>/Gd<sub>2</sub>O<sub>3</sub> nanocomposite for possible use in magnetic hyperthermia application was done by ball milling technique. The nanocomposite was characterized by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The heating efficiency and the effect of milling time (5 h and 30 h) on the structural and magnetic properties of the nanocomposite were reported. XRD analysis confirms the formation of the nanocomposite, while magnetization measurements show that the milled sample present hysteresis with low coercivity and remanence. The specific absorption rate (SAR) under an alternating magnetic field is investigated as a function of the milling time. A mean heating efficiency of 68 W/g and 28.7 W/g are obtained for 5 h and 30 h milling times respectively at 332 kHz and 170 Oe. The results showed that the obtained nanocomposite for 5 h milling time is a promising candidate for magnetic hyperthermia due to his properties which show an interesting magnetic behavior and high specific absorption rate.
基金supported by the Natural Science Foundation of China(Nos.22125902,U2032202,21975243 and 21825302)the National Program for Support of Topnotch Young Professionals,the Fundamental Research Funds for the Central Universities(No.WK2030020032)+1 种基金the DNL cooperation Fund,CAS(No.DNL202020)the Anhui Science Fund for Distinguished Young Scholars(No.2208085J15).
文摘The undesirable shuttle effect and sluggish redox kinetics of polysulfides seriously result in low sulfur utilization and poor capacity retention.Here,an integrated strategy is proposed by rational designing multifunctional architecture to manipulate the redox kinetics of polysulfides,specifically,by employing iron atoms(Fe-As)and iron-species nanoparticles(Fe-NPs)co-embedded nitrogen-doped carbon nanotube(Fe-NCNT)as catalyst and host for sulfur.The synergistic cooperation of Fe-As and Fe-NPs provides efficient active sites to facilitate the diffusion,strengthen the affinities,and promote the conversion reactions for polysulfides.Furthermore,the NCNT not only offers practical Li+transport pathways but also immobilize the polysulfides effectively.Benefiting from these merits,the Fe-NCNT/S electrodes exhibit high initial specific capacity of 1502.6 mAh/g at 0.1 C,outstanding rate performance(830 mAh/g at 2 C),and good cycling performance(597.8 mAh/g after 500 cycles with an ultralow capacity fading rate of 0.069%per cycle).This work features the distinct interaction of iron atom-nanoparticles on facilitating immobilization-diffusion-transformation process of polysulfides,and it also expected to pave the way for the application in practical Li-S batteries.
文摘Despite advances in diagnostic and therapeutic technologies for cardiovascular diseases(CVDs),it remains a leading cause of mortality and morbidity worldwide.This underscores the urgency for innovative approaches aiming at early and precise detection and treatment of CVDs to reduce the disease burden.Iron oxide nanoparticles(IONPs),with their unique magnetism and bioproperties,have shown great potential in this regard.In this review,we will begin with a brief overview of the synthesis and properties of IONPs.We will then focus on the latest applications of IONPs in CVDs,including diagnosis and treatment.The use of IONPs in the integration of diagnosis and treatment for CVDs is a promising field,and will be addressed in a separate section.The translational potential and challenges of IONPs will also be discussed.In conclusion,ongoing research and development of IONP-based strategies are highly likely to address current challenges effectively,and offer more personalized and efficient options for the diagnosis and treatment of CVDs.
基金This work was financially supported by the National Natural Science Innovative Research Group Project(No.61821002)the Key Project of the National Natural Science Foundation of China(No.92163213)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20220824)the Nanjing Science and Technology Develop-ment Foundation(No.202205066).
文摘Iron oxide nanoparticles(IONPs)modified with functional proteins hold great promise in the biomedical field.However,conventional protein modification strategies,such as adsorption and covalent coupling,are either unstable or nonspecific,or may result in the changes of protein structure and ultimately the loss of protein activity.Modification of active proteins on small-sized IONPs with a particle size of less than 30 nm is especially difficult due to their high surface energy.Herein,we developed a universal modifica-tion method based on Spy chemistry for rapid and stable protein immobilization on small-sized IONPs,which only requires the presence of active groups on the surface of nanoparticles that can couple with SpyCatcher.In short,the SpyCatcher peptides were first coated on the surface of IONPs by cross-linking with activated groups,and then the SpyTag peptide fused with a model protein(enhanced green fluo-rescent protein,EGFP)was engineered(SpyTag-EGFP)and directly coupled to SpyCatcher-modified IONPs by self-assembly,which is spontaneous and robust while avoiding the effect of chemical reactions on functional protein activity.The obtained EGFP-functionalized IONPs exhibited enhanced and stable green fluorescence and improved magnetic properties.In addition,the cell internalization efficiency of EGFP-functionalized IONPs was significantly increased as compared to unmodified IONPs,providing an ideal solution for efficient cell labeling and tracking.In conclusion,here we report a rapid and easy strategy for EGFP immobilization on IONPs based on Spy chemistry,which could be further adapted to other functional proteins in the future.SpyCatcher-modified IONPs and SpyTag-X(arbitrary functional fusion proteins)hold great potential to be applied as a versatile platform for protein immobilization on IONPs and enable its multifunctional application in the future.
基金financially supported by grants 17210219 and T21-711/16R from the Research Grants Council of the Hong Kong governmentproject 51978369 from the National Natural Science Foundation of China。
文摘Sustainable metal-air batteries demand high-efficiency,environmentally-friendly,and non-precious metal-based electrocatalysts with bifunctionality for both the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).In this research,novel functional carbon nanotubes with multi-active sites including well-dispersed single-atom iron throughout the walls and encapsulated ultrafine iron nanoparticles were synthesized as an electrocatalyst(FeNP@Fe-N-C)through one-step pyrolysis of metal-organic frameworks.High-resolution synchrotron powder X-ray diffraction and X-ray absorption spectroscopy were applied to characterize the unique structure of the electrocatalyst.In comparison to the commercial Pt/C and Ru O_(2)electrodes,the newly prepared FeNP@Fe-N-C presented a superb bifunctional performance with its narrow potential difference(Egap)of 0.73 V,which is ascribed to the metallic Fe nanoparticles that boosts the adsorption and activation of oxygen on the active sites with an enhanced O_(2)adsorption capacity of 7.88 cm^(3)g^(-1)and synergistically functionalizes the iron atoms dispersed on the nanotubes.A rechargeable zinc-air battery based on FeNP@Fe-N-C exhibited a superior open-circuit voltage(1.45 V),power density(106.5 m W cm^(-2)),and stable cycling performance.The green technique developed in this work for the fabrication of functional nanotubes raises the prospect of making more efficient electrocatalysts for sustainable energy cells.
基金financially supported by the National Natural Science Foundation of China(91545202,91945302)the Strategic Priority Research Program of the Chinese Academy of Sciences(CAS,XDB17000000,XDB36030200)+4 种基金the Ministry of Science and Technology of China(2018YFA0704503)the Liao Ning Revitalization Talents Program(XLYC1807066,XLYC1907099)the Youth Innovation Promotion Association of CAS(Y201829)the State Key Laboratory of Catalysis in DICP(No.N-19-13)the DNL Cooperation Fund,CAS(DNL202003)。
文摘CO_(2)electroreduction reaction(CO_(2)RR),combined with solid oxide electrolysis cells(SOECs),is a feasible technology for the storage of renewable electric energy,while its development is limited by the catalytic activity and stability on cathodes.Here,a novel garnet oxide(Gd_(3)Fe_(5)O_(12))cathode is designed,where the garnet oxide is converted to perovskite oxide and iron via in situ electrochemical phase transition during CO_(2)electroreduction,resulting in high activity with Faradaic efficiency close to 100%and great stability over 1000 h galvanostatic test.A variety of experimental characterizations and density functional theory calculations indicate that in situ exsolved Fe clusters can effectively enhance the adsorption energies of intermediates and lowering the CO_(2)dissociation barriers.Microkinetic modelling confirms that CO_(2)RR goes through a dissociative adsorption mechanism and the electronic transfer for CO_(2)dissociation is the rate-determining step.
基金Sponsored by the National Natural Science Foundation for Youth of China(Grant No.51308149)Major Science and Technology Program for Water Pollution Control Treatment(Grant No.2014ZX07201-012+1 种基金2013ZX07201007-001)State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology)(Grant No.2014TS08)
文摘Anaerobic digestion is widely used in the treatment of industrial wastewater,excess activated sludge,municipal waste,crop straw and livestock manure,with the functions of environmental protection and energy recovery. This review summarizes and evaluates the present knowledge of effects of different states of Fe( ZVI,Fe( II),Fe( III)) on hydrogen and methane production in anaerobic digestion process. The potential promotion effects of iron oxides nanoparticles( IONPs),especially magnetite nanoparticles on anaerobic digestion are also mentioned. Fe plays important role in transporting electron,stimulating bacterial growth and increasing hydrogen and methane production rate by promoting enzyme activity. Adding Fe with different morphologies and valence states in anaerobic digestion to increase biogas( hydrogen and methane) production and enhance organic matter degradation simultaneously,which has attracted many scientists' attention in recent years. Rapid progress in this area has been made over the last few years,since Fe is essential to the fermentative hydrogen and methane production,while few is known about how Fe affects the fermentative biogas production. This review is significant to maintain the stable operation of the biogas project.
基金supported by the National Natural Science Foundation of China (Grant Nos. 91859201, 92159305, 81971625, and 82030047)
文摘Despite being a common therapy for hepatocellular carcinoma(HCC),insufficient thermal ablation can leave behind tumor residues that can cause recurrence.This is believed to augment M2 inflammatory macrophages that usually play a pro-tumorigenic role.To address this problem,we designed D-mannose-chelated iron oxide nanoparticles(man-IONPs) to polarize M2-like macrophages into the antitumor Ml phenotype.In vitro and in vivo experiments demonstrated that man-IONPs specifically targeted M2-like macrophages and accumulated in peri-ablation zones after macrophage infiltration was augmented under insufficient microwave ablation(MWA).The nanoparticles simultaneously induced polarization of pro-tumorigenic M2 macrophages into antitumor M1 phenotypes,enabling the transformation of the immunosuppressive microenvironment into an immunoactivating one.Post-MWA macrophage polarization exerted robust inhibitory effects on HCC progression in a well-established orthotopic liver cancer mouse model.Thus,combining thermal ablation with man-IONPs can salvage residual tumors after insufficient MWA.These results have strong potential for clinical translation.
基金supported by grants from Natural Science Foundation of China(No.81772373,No.81572167)by Shanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant Support,the SHIPM-pi fund No.JY201804&No.JC201801 from Shanghai Institute of Precision Medicine,Ninth People's Hospital Shanghai Jiao Tong University,Shanghai Jiao Tong University School of Medicine,and by the Foundation of National Facility for Translational Medicine(Shanghai)(No.TMSK-2020-119).
文摘Breast cancer bone metastasis poses significant challenge for therapeutic strategies.Inside the metastatic environment,osteoclasts and tumor cells interact synergistically to promote cancer progression.In this study,the proprotein convertase furin is targeted due to its critical roles in both tumor cell invasion and osteoclast function.Importantly,the furin inhibitor is specifically delivered by bone targeting superparamagnetic iron oxide(SPIO)nanoparticles.Our in vitro and in vivo data demonstrate that this system can effectively inhibit both osteoclastic bone resorption and breast cancer invastion,leading to alleviated osteolysis.Therefore,the bone targeting&furin inhibition nanoparticle system is a promising therapeutic and diagnostic strategy for breast cancer bone metastasis.
基金the Innovative Research Groups of the National Natural Science Foundation of China(no.81621003)National Key Basic Research Program of China(no.2013CB933903)+1 种基金Sichuan Science and Technology Program(no.2019JDRC0103)China Postdoctoral Science Foundation Funded Project(no.2015M572475).
文摘Dextran-coated superparamagnetic iron oxide nanoparticles(Dex-SPIONs)are excellent magnetic resonance imaging contrast agents for disease diagnosis and therapy.They can be delivered to target tissues mainly though vascular endothelium cells,which are major targets of oxidative stress.In cardiovascular cells,autophagy serves primarily on a pro-survival approach that protects the cells from oxidative stress even some autophagy inducers have been developed for adjuvant therapy of cardiovascular disorders.Our study demonstrated that the nanoparticles could be taken up by human umbilical vein endothelial cells(HUVECs)without causing obvious cytotoxicity but triggering autophagy.Furthermore,our results revealed that Dex-SPIONs could enhance HUVECs survival and reverse the reduction of nitric oxide secretion under the condition of H2O2 damage.However,these effects could be diminished by the autophagy inhibitor.In particular,we discovered that Dex-SPIONs evoked autophagy in HUVECs by reducing the phosphorylation of PRAS40,an upstream regulator of autophagy initiation.These results suggested that Dex-SPIONs functions as an autophagic-related antioxidant in HUVECs which may be utilized as an adjuvant therapy to cardiovascular disease associated with oxidative stress.
基金supported by the National Natural Science Foundation of China(81601607 and 81971609)Chongqing High-level Personnel of Special Support Program(Youth Top-notch Talent CQYC201905077)Creative Research Group of CQ University(CXQT21017).
文摘Iron oxide nanoparticle(IONP)with unique magnetic property and high biocompatibility have been widely used as magnetic resonance imaging(MRI)contrast agent(CA)for long time.However,a review which comprehensively summarizes the recent development of IONP as traditional T_(2) CA and its new application for different modality of MRI,such as T_(1) imaging,simultaneous T_(2)/T_(1) or MRI/other imaging modality,and as environment responsive CA is rare.This review starts with an investigation of direction on the development of high-performance MRI CA in both T_(2) and T_(1) modal based on quantum mechanical outer sphere and Solomon-Bloembergen-Morgan(SBM)theory.Recent rational attempts to increase the MRI contrast of IONP by adjusting the key parameters,including magnetization,size,effective radius,inhomogeneity of surrounding generated magnetic field,crystal phase,coordination number of water,electronic relaxation time,and surface modification are summarized.Besides the strategies to improve r2 or r1 values,strategies to increase the in vivo contrast efficiency of IONP have been reviewed from three different aspects,those are introducing second imaging modality to increase the imaging accuracy,endowing IONP with environment response capacity to elevate the signal difference between lesion and normal tissue,and optimizing the interface structure to improve the accumulation amount of IONP in lesion.This detailed review provides a deep understanding of recent researches on the development of high-performance IONP based MRI CAs.It is hoped to trigger deep thinking for design of next generation MRI CAs for early and accurate diagnosis.
