In order to overcome all encapsulation variations during a complex coacervation process, the replacement of gelatin cationic polymer has been performed using p(AMA). The synthesis of p(AMA) was realized through a rand...In order to overcome all encapsulation variations during a complex coacervation process, the replacement of gelatin cationic polymer has been performed using p(AMA). The synthesis of p(AMA) was realized through a random radical methodology. Under these conditions a polymer with 18,600 g/mol was found appropriate for optimal capsule yield and physico-chemical properties. Turbidity measurements performed during the coacervation reactions with different ratios of both CMC and p(AMA) allowed optimizing coacervation conditions. Coacervates characterizations particularly demonstrate the stability of the capsules exhibiting a break strength over 3 N/m<sup>2</sup>.展开更多
The experiment adopts complex coacervation to prepare microcapsules. Through the experimental comparison, soybean protein isolated-maltodextrin is determined as the wall material for the experimental preparation of th...The experiment adopts complex coacervation to prepare microcapsules. Through the experimental comparison, soybean protein isolated-maltodextrin is determined as the wall material for the experimental preparation of the microcapsules of kiwi fruit seed oil. This paper researched the effects of wall material concentration, core wall ratio and other factors on complex coacervation of kiwi fruit seed oil microcapsules embedding rate, determining that the best wall material concentration is 1%, core wall ratio is 1:1, and the optimum pH ratio is 3.0, temperature is 40°C, and the optimum curing time is 6 hours. The experiment carried out half life research on the microcapsules prepared by the complex coacervation of kiwi fruit seed oil microcapsule. By calculation: the degradation rate constant of kiwi fruit seed oil microcapsules prepared by complex coacervation is 2.793. According to the regression equation it can calculate the half life of kiwi fruit seed oil microcapsules is 18.58 months, about a year and a half.展开更多
Discharge of whey proteins is still a current practice by small cheese producers. The development of low-cost alternatives for recovery of these proteins is fundamental for small producers who cannot apply expensive t...Discharge of whey proteins is still a current practice by small cheese producers. The development of low-cost alternatives for recovery of these proteins is fundamental for small producers who cannot apply expensive techniques. The present study investigated the complex coacervation technique as a cheap technology to recover proteins from sweet whey using carboxymethylcellulose, and the coacervate used as an ingredient in the formulation of probiotic fermented milk. The nutritional properties of whey-carboxymethylcellulose coacervates (WP-CMC) were evaluated in trials with animals (rats) using casein as a reference. All these parameters—the coefficient of feed efficiency (CEA), protein digestibility-corrected amino acid score (PDCAAS), and net protein ratio (NPR), as well as weight gain—were determined to evaluate protein quality. A sensory acceptance test was applied to evaluate the sensory characteristics of the product. The complex coacervation technique recovered 86% of the protein from sweet whey. No significant (p > 0.05) differences were observed in the biological tests for both groups (WP-CMC and Casein groups) when NPR (4.98 to 5.04), digestibility (92.35 to 90.64), and CEA (0.40 to 0.42) were evaluated. Probiotic fermented milk beverage containing WP-CMC (0.78%) and guar gum (0.68%) presented good acceptability as determined by sensory evaluation. WP-CMC can be considered an ingredient with high nutritional and biological value that could be applied in probiotic fermented milk as an alternative to small producers to allocate the residual whey from cheese manufacture.展开更多
We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a ...We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a supercritical CO2 solution.? A suspension of CaCO3 in CO2 and dissolved poly(HDFDA) were mixed in supercritical CO2.? After the system pressure was slowly decreased to atmospheric pressure, the microcapsules were obtained.? Coacervation was achieved by the precipitation of poly(HDFDA) during the decrease in the pressure of CO2;the solubility of poly(HDFDA) in CO2 decreased with the pressure.? The structure and morphology of the microparticles were investigated by using a scanning electron microscope (SEM) and an electron probe microanalyzer (EPMA) equipped with a wavelength dispersive X-ray spectroscope (WDX).展开更多
For more than a decade,the discovery of liquid–liquid phase separation within living organisms has prompted colloid scientists to understand the connection between coacervate functionality,phase behavior,and dynamics...For more than a decade,the discovery of liquid–liquid phase separation within living organisms has prompted colloid scientists to understand the connection between coacervate functionality,phase behavior,and dynamics at a multidisciplinary level.Although the protein–polysaccharide was the first system in which the coacervation phenomenon was discovered and is widely used in food systems,the phase state and relaxation dynamics of protein–polysaccharide complex coacervates(PPCC)have rarely been discussed previously.Consequently,this review aims to unravel the relationship between PPCC dynamics,thermodynamics,molecular architecture,applications,and phase states in past studies.Looking ahead,solving the way molecular architecture spreads to macro-functionality,that is,establishing the relationship between molecular architecture–dynamics–application,will catalyze novel advancements in PPCC research within the field of foods and biomaterials.展开更多
To improve the oxidative stability and application of fish oil, it was microencapsulated by simple coacervation followed by spray drying. Simple coacervation took place by adding malt dextrin into the emulsion of fish...To improve the oxidative stability and application of fish oil, it was microencapsulated by simple coacervation followed by spray drying. Simple coacervation took place by adding malt dextrin into the emulsion of fish oil and hydroxypropyl methylcellulose （HPMC） solution. Influences of several process parameters on the microencapsulation were evaluated and the oxidative stability and microstructure of microcapsules were analyzed. Results showed that the coacervation could be observed only when dextrose equivalent value （DE value） of malt dextrin, concentration of HPMC solution and fish oil percentage in microcapsules were no more than 20. 5% and 40%, respectively. Moreover, microencapsulation efficiency was higher at HPMC solution concentration of 4% and fish oil percentage of less than 30%. The oxidative stability of fish oil was improved by the microencapsulation and done best in the ease of replacing malt dextrin by 40% with acacia. Scanning electronic microscopic photographs showed that the microcapsule obtained was a round, smooth and hollow microcapsule with its wall made up of innumerable small and solid submicrocapsules with the core of fish oil.展开更多
Complex coacervation of whey protein（WP） with acacia gum（AG） was carried out in water with the presence of dodecyl acetate （DA）,a component of insect sex pheromones,in order to obtain microcapsules with DA as th...Complex coacervation of whey protein（WP） with acacia gum（AG） was carried out in water with the presence of dodecyl acetate （DA）,a component of insect sex pheromones,in order to obtain microcapsules with DA as the core material and WP-AG coacervate as the wall materials.Through variations in wall/core ratios,concentrations of the wall materials in capsule preparations,DA encapsulation was optimized,which showed a high DA encapsulation was achieved when coacervation was conducted at pH 3.5 with wall/core mass ratio at 3 combined with concentration of wall materials at 1.0 wt%.Morphology and the structure of DA loaded microcapsules were examined by scanning electron microscope,which showed the microcapsules were of core/shell structure with DA encapsulated in the inner of the microcapsules.DA release was examined and the behavior of the release was discussed.展开更多
Adhesives have attracted a great deal of attention as an advanced modality in biomedical engineering because of their unique wound management behavior.However,it is a grand challenge for current adhesive systems to ac...Adhesives have attracted a great deal of attention as an advanced modality in biomedical engineering because of their unique wound management behavior.However,it is a grand challenge for current adhesive systems to achieve robust adhesion due to their tenuous interfacial bonding strength.Moreover,the absence of dynamic adaptability in conventional chemical adhesives restricts neoblasts around the wound from migrating to the site,resulting in an inferior tissue-regeneration effect.Herein,an extracellular matrix-derived biocomposite adhesive with robust adhesion and a real-time skin healing effect is well-engineered.Liquid–liquid phase separation is well-harnessed to drive the assembly of the biocomposite adhesive,with the active involvement of supramolecular interactions between chimeric protein and natural DNA,leading to a robustly reinforced adhesion performance.The bioadhesive exhibits outstanding adhesion and sealing behaviors,with a sheared adhesion strength of approximately 18 MPa,outperforming its reported counterparts.Moreover,the engineered bioderived components endow this adhesive material with biocompatibility and exceptional biological functions including the promotion of cell proliferation and migration,such that the use of this material eventually yields real-time in situ skin regeneration.This work opens up novel avenues for functionalized bioadhesive engineering and biomedical translations.展开更多
With Perfume as core and gelatin-gum arabic as mem-brane,a series of microcapsules were prepared by meansof complex coacervation at various technical conditions.Their interior and outer diameters and membrane thick-ne...With Perfume as core and gelatin-gum arabic as mem-brane,a series of microcapsules were prepared by meansof complex coacervation at various technical conditions.Their interior and outer diameters and membrane thick-nesses were measured and the effects of preparation tech-niques on microcapsule properties were revealed.展开更多
Hexafluoroisopropanol(HFIP)-induced sodium dodecyl sulfate/dodecyltrimethylammonium bromide(SDS/DTAB) catanionic surfactant coacervate extraction method coupled with high performance liquid chromatography(HPLC) was us...Hexafluoroisopropanol(HFIP)-induced sodium dodecyl sulfate/dodecyltrimethylammonium bromide(SDS/DTAB) catanionic surfactant coacervate extraction method coupled with high performance liquid chromatography(HPLC) was used to detect the migration of phthalates from disposable tablewares to drinking water. The concentration factors are larger than 82 and extraction recoveries over 53% for water samples spiked with 100 or 200 ng/m L phthalates. Limit of detection is in the range of 1.0–2.6 ng/m L.Good linearity with correlation coefficients larger than 0.9985 is obtained in the concentration of20–1500 or 40–3000 ng/m L. Relative recoveries are from 82.4% to 123.6% for water samples spiked with30/60, 250/500, and 1500/3000 ng/m L phthalates, respectively. Relative standard deviations(RSDs) are0.4%–7.4% for intraday precision(n = 5) and 0.6%–7.8% for interday precision(n = 3). Four of studied phthalates are found in the drinking water samples prepared from four kinds of tablewares.展开更多
Distribution of TX114 between coacervate and aqueous phases in clouding of various initial TX114 concentrations was studied. Effects of temperature and salinity （Na2SO4） on the distribution of TX114 concentration we...Distribution of TX114 between coacervate and aqueous phases in clouding of various initial TX114 concentrations was studied. Effects of temperature and salinity （Na2SO4） on the distribution of TX114 concentration were also investigated. Differing from the nonionic surfactant C12E10, the distribution of TX114 is sensitive to the temperature, and it is observed that the TX114 concentration in the aqueous phase （Caq） does not depend on the initial TX114 concentration apparently at 45℃, and the Caq decreases with an increase of NazSO4 concentration. Low initial TX114 concentration in unclouded solutions, high Na2SO4 concentration, and temperature are suggested to control the surfactant loss in large-scale cloud point extraction applications.展开更多
The microstructure of CdI2 thin film grown during vapor-phase deposition was investigated by scanning electron microscopy (SEM). The thin film deposited on Si crystal consists of numerous sunflower-like aggregates. Th...The microstructure of CdI2 thin film grown during vapor-phase deposition was investigated by scanning electron microscopy (SEM). The thin film deposited on Si crystal consists of numerous sunflower-like aggregates. These aggregates display well self-assembly characteristics. The size of Sunflower-like aggregates is between 12 and 44 μm. Each sunflower-like aggregate is surrounded with many adjacent wings-'petals'. The structure of central region of the 'sunflower' is obviously difFerent from that of the 'petal'. Electron spectroscopy for chemical analysis (ESCA) was employed in determining the chemical valence of the thin film. Self-organization efFect is used to explain the coring growth process of CdI2 thin film展开更多
Engineering hydrogels that resemble biological tissues of various lengths via conventional fabrication techniques remains challenging.Three-dimensional(3D)bioprinting has emerged as an advanced approach for constructi...Engineering hydrogels that resemble biological tissues of various lengths via conventional fabrication techniques remains challenging.Three-dimensional(3D)bioprinting has emerged as an advanced approach for constructing complex biomimetic 3D architectures,which are currently restricted by the limited number of available bioinks with high printability,biomimicry,biocompatibility,and proper mechanical properties.Inspired by ubiquitous coacervation phenomena in biology,we present a unique mineral-biopolymer coacervation strategy that enables the hierarchical assembly of nanoclay and recombinant human collagen(RHC).This system was observed to undergo a coacervation transition(liquid‒liquid phase separation)spontaneously.The formed dense phase separated from its supernatant is the coacervate of clay-RHC-rich complexes,where polymer chains are sandwiched between silicate layers.Molecular dynamics simulation was first used to verify and explore the coacervation process.Then,the coacervates were demonstrated to be potential bioinks that exhibited excellent self-supporting and shear-thinning viscoelastic properties.Through extrusion-based printing,the versatility of the bioink was demonstrated by reconstructing the key features of several biological tissues,including multilayered lattice,vascular,nose,and ear-like structures,without the need for precrosslinking operations or support baths.Furthermore,the printed scaffolds were cytocompatible,elicited minimal inflammatory responses,and promoted bone regeneration in calvarial defects.展开更多
The liquid-liquid phase separation of biopolymers in living cells contains multiple interactions and occurs in a dynamic environment.Resolving the regulation mechanism is still a challenge.In this work,we designed a s...The liquid-liquid phase separation of biopolymers in living cells contains multiple interactions and occurs in a dynamic environment.Resolving the regulation mechanism is still a challenge.In this work,we designed a series of peptides(XXLY)_(6)SSSGSS and studied their complexation and coacervation behavior with single-stranded oligonucleotides.The“X”and“Y”are varied to combine known amounts of charged and non-charged amino acids,together with the introduction of secondary structures and pH responsiveness.Results show that the electrostatic interaction,which is described as charge density,controls both the strength of complexation and the degree of chain relaxation,and thus determines the growth and size of the coacervates.The hydrophobic interaction is prominent when the charges are neutralized.Interestingly,the secondary structures of peptides exhibit profound effect on the morphology of the phases,such as solid phase to liquid phase transition.Our study gains insight into the phase separation under physiological conditions.It is also helpful to create coacervates with desirable structures and functions.展开更多
Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding a...Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion failure.Thus,the design of adhesives for natural seawater represents challenges less resolved.Herein,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural seawater.By combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in seawater.The instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural seawater.The design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.展开更多
Controlled delivery of proteins and other biologics is a growing medium of therapy for diseases previously untreatable.Here we report a self-assembling,tunable vesicle for the controlled delivery of growth factors and...Controlled delivery of proteins and other biologics is a growing medium of therapy for diseases previously untreatable.Here we report a self-assembling,tunable vesicle for the controlled delivery of growth factors and cytokines.Coacervate made of heparin and a biocompatible polycation,PEAD,forms the core of the vesicle;lipids form the membrane of the vesicle.We call this vesicle lipocoacervate(LipCo),which has a high affinity for growth factors and cytokines due to heparin.LipCo is a tunable protein delivery vehicle.The vesicle size is controlled through polymer and salt concentrations.Membrane functionalization enables potential for targeting capabilities with long-term storage through lyophilization.Importantly,the controlled delivery of therapeutics also avoids high toxicity to treated cells in vitro.Here we report on these key principles of LipCo assembly and design.展开更多
Developing an oral in situ-forming hydrogel that targets the inflamed intestine to suppress bleeding ulcers and alleviate intestinal inflammation is crucial for effectively treating ulcerative colitis(UC).Here,inspire...Developing an oral in situ-forming hydrogel that targets the inflamed intestine to suppress bleeding ulcers and alleviate intestinal inflammation is crucial for effectively treating ulcerative colitis(UC).Here,inspired by sandcastle worm adhesives,we proposed a water-immiscible coacervate(EMNs-gel)with a programmed coacervate-to-hydrogel transition at inflammatory sites composed of dopa-rich silk fibroin matrix containing embedded inflammation-responsive core-shell nanoparticles.Driven by intestinal peristalsis,the EMNs-gel can be actuated forward and immediately transform into a hydrogel once contacting with the inflamed intestine to yield strong tissue adhesion,resulting from matrix metalloproteinases(MMPs)-triggered release of Fe3+from embedded nanoparticles and rearrangement of polymer network of EMNs-gel on inflamed intestine surfaces.Extensive in vitro experiments and in vivo UC models confirmed the preferential hydrogelation behavior of EMNs-gel to inflamed intestine surfaces,achieving highly effective hemostasis,and displaying an extended residence time(48 h).This innovative EMNs-gel provides a non-invasive solution that accurately suppresses severe bleeding and improves intestinal homeostasis in UC,showcasing great potential for clinical applications.展开更多
Insufficient metabolic energy,in the form of adenosine triphosphate(ATP),and bacterial infections are among the main causes for the development of chronic wounds.Previously we showed that the physi-ological inorganic ...Insufficient metabolic energy,in the form of adenosine triphosphate(ATP),and bacterial infections are among the main causes for the development of chronic wounds.Previously we showed that the physi-ological inorganic polymer polyphosphate(polyP)massively accelerates wound healing both in animals(diabetic mice)and,when incorporated into mats,in patients with chronic wounds.Here,we focused on a hydrogel-based gel formulation,supplemented with both soluble sodium polyP(Na-polyP)and amor-phous calcium polyP nanoparticles(Ca-polyP-NP).Exposure of human epidermal keratinocytes to the gel caused a significant increase in extracellular ATP level,an effect that was even enhanced when Na-polyP was combined with Ca-polyP-NP.Furthermore,it is shown that the added polyP in the gel is converted into a coacervate,leading to encapsulation and killing of bacteria.The data on human chronic wounds showed that the administration of hydrogel leads to the complete closure of these wounds.Histological analysis of biopsies showed an increased granulation of the wounds and an enhanced microvessel forma-tion.The results indicate that the polyP hydrogel,due to its properties to entrap bacteria and generate metabolic energy,is a very promising formulation for a new therapy for chronic wounds.展开更多
Protecting the skin from UV light irradiation in wet and underwater environments is challenging due to the weak adhesion of existing sunscreen materials but highly desired.Herein we report a polyethyleneimine/thioctic...Protecting the skin from UV light irradiation in wet and underwater environments is challenging due to the weak adhesion of existing sunscreen materials but highly desired.Herein we report a polyethyleneimine/thioctic acid/titanium dioxide(PEI/TA/TiO_(2))coacervate-derived hydrogel with robust,asymmetric,and reversible wet bioadhesion and effective UV-light-shielding ability.The PEI/TA/TiO_(2)complex coacervate can be easily obtained by mixing a PEI solution and TA/TiO_(2)powder.The fluid PEI/TA/TiO_(2)coacervate deposited on wet skin can spread into surface irregularities and subsequently transform into a hydrogel with increased cohesion,thereby establishing interdigitated contact and adhesion between the bottom surface and skin.Meanwhile,the functional groups between the skin and hydrogel can form physical interactions to further enhance bioadhesion,whereas the limited movement of amine and carboxyl groups on the top hydrogel surface leads to low adhesion.Therefore,the coacervate-derived hydrogel exhibits asymmetric adhesiveness on the bottom and top surfaces.Moreover,the PEI/TA/TiO_(2)hydrogel formed on the skin could be easily removed using a NaHCO3 aqueous solution without inflicting damage.More importantly,the PEI/TA/TiO_(2)hydrogel can function as an effective sunscreen to block UV light and prevent UV-induced MMP-9 overexpression,inflammation,and DNA damage in animal skin.The advantages of PEI/TA/TiO_(2)coacervate-derived hydrogels include robust,asymmetric,and reversible wet bioadhesion,effective UV light-shielding ability,excellent biocompatibility,and easy preparation and usage,making them a promising bioadhesive to protect the skin from UV light-associated damage in wet and underwater environments.展开更多
Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets...Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets are established as a model of artificial membraneless organelles in endothelial dysfunctional cells for the cascade enzymatic production of nitric oxide(NO) with a purpose of correcting cellular NO deficiency. We prepared the coacervate microdroplets via liquid-liquid phase separation of oppositely charged polyelectrolytes, in which glucose oxidase/horseradish peroxidase-mediated cascade reaction was compartmented. After the coacervate microdroplets were implanted in NO-deficient dysfunctional cells, the compartments maintained a phase-separated liquid droplet structure, which facilitated a significant enhancement of NO production in the dysfunctional cells. The recovery of NO production was further exploited to inhibit clot formation in blood plasma located in the cell suspension. This demonstrated a proof-of-concept design of artificial organelles in dysfunctional cells for cell repair and anticoagulation-related medical applications. Our results demonstrate an approach for the construction of coacervate droplets through phase separation for the generation of artificial membraneless organelles, which can be designed to provide an array of functionalities in living organisms that have the potential to be used in the field of cell engineering and medical therapy.展开更多
文摘In order to overcome all encapsulation variations during a complex coacervation process, the replacement of gelatin cationic polymer has been performed using p(AMA). The synthesis of p(AMA) was realized through a random radical methodology. Under these conditions a polymer with 18,600 g/mol was found appropriate for optimal capsule yield and physico-chemical properties. Turbidity measurements performed during the coacervation reactions with different ratios of both CMC and p(AMA) allowed optimizing coacervation conditions. Coacervates characterizations particularly demonstrate the stability of the capsules exhibiting a break strength over 3 N/m<sup>2</sup>.
文摘The experiment adopts complex coacervation to prepare microcapsules. Through the experimental comparison, soybean protein isolated-maltodextrin is determined as the wall material for the experimental preparation of the microcapsules of kiwi fruit seed oil. This paper researched the effects of wall material concentration, core wall ratio and other factors on complex coacervation of kiwi fruit seed oil microcapsules embedding rate, determining that the best wall material concentration is 1%, core wall ratio is 1:1, and the optimum pH ratio is 3.0, temperature is 40°C, and the optimum curing time is 6 hours. The experiment carried out half life research on the microcapsules prepared by the complex coacervation of kiwi fruit seed oil microcapsule. By calculation: the degradation rate constant of kiwi fruit seed oil microcapsules prepared by complex coacervation is 2.793. According to the regression equation it can calculate the half life of kiwi fruit seed oil microcapsules is 18.58 months, about a year and a half.
文摘Discharge of whey proteins is still a current practice by small cheese producers. The development of low-cost alternatives for recovery of these proteins is fundamental for small producers who cannot apply expensive techniques. The present study investigated the complex coacervation technique as a cheap technology to recover proteins from sweet whey using carboxymethylcellulose, and the coacervate used as an ingredient in the formulation of probiotic fermented milk. The nutritional properties of whey-carboxymethylcellulose coacervates (WP-CMC) were evaluated in trials with animals (rats) using casein as a reference. All these parameters—the coefficient of feed efficiency (CEA), protein digestibility-corrected amino acid score (PDCAAS), and net protein ratio (NPR), as well as weight gain—were determined to evaluate protein quality. A sensory acceptance test was applied to evaluate the sensory characteristics of the product. The complex coacervation technique recovered 86% of the protein from sweet whey. No significant (p > 0.05) differences were observed in the biological tests for both groups (WP-CMC and Casein groups) when NPR (4.98 to 5.04), digestibility (92.35 to 90.64), and CEA (0.40 to 0.42) were evaluated. Probiotic fermented milk beverage containing WP-CMC (0.78%) and guar gum (0.68%) presented good acceptability as determined by sensory evaluation. WP-CMC can be considered an ingredient with high nutritional and biological value that could be applied in probiotic fermented milk as an alternative to small producers to allocate the residual whey from cheese manufacture.
文摘We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a supercritical CO2 solution.? A suspension of CaCO3 in CO2 and dissolved poly(HDFDA) were mixed in supercritical CO2.? After the system pressure was slowly decreased to atmospheric pressure, the microcapsules were obtained.? Coacervation was achieved by the precipitation of poly(HDFDA) during the decrease in the pressure of CO2;the solubility of poly(HDFDA) in CO2 decreased with the pressure.? The structure and morphology of the microparticles were investigated by using a scanning electron microscope (SEM) and an electron probe microanalyzer (EPMA) equipped with a wavelength dispersive X-ray spectroscope (WDX).
基金China Postdoctoral Science Foundation,Grant/Award Number:2023M731135Ministry of Science and Technology of the People’s Republic of China,Grant/Award Number:DL2022163005L+2 种基金National Natural Science Foundation of China,Grant/Award Number:32172257Higher Education Discipline Innovation Project,Grant/Award Number:B17018Postdoctoral Innovative Talent Support Program,Grant/Award Number:BX20230130。
文摘For more than a decade,the discovery of liquid–liquid phase separation within living organisms has prompted colloid scientists to understand the connection between coacervate functionality,phase behavior,and dynamics at a multidisciplinary level.Although the protein–polysaccharide was the first system in which the coacervation phenomenon was discovered and is widely used in food systems,the phase state and relaxation dynamics of protein–polysaccharide complex coacervates(PPCC)have rarely been discussed previously.Consequently,this review aims to unravel the relationship between PPCC dynamics,thermodynamics,molecular architecture,applications,and phase states in past studies.Looking ahead,solving the way molecular architecture spreads to macro-functionality,that is,establishing the relationship between molecular architecture–dynamics–application,will catalyze novel advancements in PPCC research within the field of foods and biomaterials.
基金Project supported by the Doctoral Foundation of Guangdong Natural Science Foundation （No. 04300744）.
文摘To improve the oxidative stability and application of fish oil, it was microencapsulated by simple coacervation followed by spray drying. Simple coacervation took place by adding malt dextrin into the emulsion of fish oil and hydroxypropyl methylcellulose （HPMC） solution. Influences of several process parameters on the microencapsulation were evaluated and the oxidative stability and microstructure of microcapsules were analyzed. Results showed that the coacervation could be observed only when dextrose equivalent value （DE value） of malt dextrin, concentration of HPMC solution and fish oil percentage in microcapsules were no more than 20. 5% and 40%, respectively. Moreover, microencapsulation efficiency was higher at HPMC solution concentration of 4% and fish oil percentage of less than 30%. The oxidative stability of fish oil was improved by the microencapsulation and done best in the ease of replacing malt dextrin by 40% with acacia. Scanning electronic microscopic photographs showed that the microcapsule obtained was a round, smooth and hollow microcapsule with its wall made up of innumerable small and solid submicrocapsules with the core of fish oil.
文摘Complex coacervation of whey protein（WP） with acacia gum（AG） was carried out in water with the presence of dodecyl acetate （DA）,a component of insect sex pheromones,in order to obtain microcapsules with DA as the core material and WP-AG coacervate as the wall materials.Through variations in wall/core ratios,concentrations of the wall materials in capsule preparations,DA encapsulation was optimized,which showed a high DA encapsulation was achieved when coacervation was conducted at pH 3.5 with wall/core mass ratio at 3 combined with concentration of wall materials at 1.0 wt%.Morphology and the structure of DA loaded microcapsules were examined by scanning electron microscope,which showed the microcapsules were of core/shell structure with DA encapsulated in the inner of the microcapsules.DA release was examined and the behavior of the release was discussed.
基金supported by the National Key Research and Development Program of China(2022YFA0913200 and 2021YFB3502300)the National Natural Science Foundation of China(22020102003,22125701,22277064,82272161,52222214,and 22107097)+3 种基金Beijing Municipal Science and Technology Commission(221100007422088)Beijing Nova Program(Z211100002121132)Beijing Natural Science Foundation(2222010)Xiangfu Lab Research Project(XF012022C0200)。
文摘Adhesives have attracted a great deal of attention as an advanced modality in biomedical engineering because of their unique wound management behavior.However,it is a grand challenge for current adhesive systems to achieve robust adhesion due to their tenuous interfacial bonding strength.Moreover,the absence of dynamic adaptability in conventional chemical adhesives restricts neoblasts around the wound from migrating to the site,resulting in an inferior tissue-regeneration effect.Herein,an extracellular matrix-derived biocomposite adhesive with robust adhesion and a real-time skin healing effect is well-engineered.Liquid–liquid phase separation is well-harnessed to drive the assembly of the biocomposite adhesive,with the active involvement of supramolecular interactions between chimeric protein and natural DNA,leading to a robustly reinforced adhesion performance.The bioadhesive exhibits outstanding adhesion and sealing behaviors,with a sheared adhesion strength of approximately 18 MPa,outperforming its reported counterparts.Moreover,the engineered bioderived components endow this adhesive material with biocompatibility and exceptional biological functions including the promotion of cell proliferation and migration,such that the use of this material eventually yields real-time in situ skin regeneration.This work opens up novel avenues for functionalized bioadhesive engineering and biomedical translations.
文摘With Perfume as core and gelatin-gum arabic as mem-brane,a series of microcapsules were prepared by meansof complex coacervation at various technical conditions.Their interior and outer diameters and membrane thick-nesses were measured and the effects of preparation tech-niques on microcapsule properties were revealed.
基金the National Natural Science Foundation of China(Grant no.81373045)the Provincial Natural Science Foundation of Hubei of China(Grant no.2015CFA139)
文摘Hexafluoroisopropanol(HFIP)-induced sodium dodecyl sulfate/dodecyltrimethylammonium bromide(SDS/DTAB) catanionic surfactant coacervate extraction method coupled with high performance liquid chromatography(HPLC) was used to detect the migration of phthalates from disposable tablewares to drinking water. The concentration factors are larger than 82 and extraction recoveries over 53% for water samples spiked with 100 or 200 ng/m L phthalates. Limit of detection is in the range of 1.0–2.6 ng/m L.Good linearity with correlation coefficients larger than 0.9985 is obtained in the concentration of20–1500 or 40–3000 ng/m L. Relative recoveries are from 82.4% to 123.6% for water samples spiked with30/60, 250/500, and 1500/3000 ng/m L phthalates, respectively. Relative standard deviations(RSDs) are0.4%–7.4% for intraday precision(n = 5) and 0.6%–7.8% for interday precision(n = 3). Four of studied phthalates are found in the drinking water samples prepared from four kinds of tablewares.
基金Supported by the National Natural Science Foundation of China （20676069）.
文摘Distribution of TX114 between coacervate and aqueous phases in clouding of various initial TX114 concentrations was studied. Effects of temperature and salinity （Na2SO4） on the distribution of TX114 concentration were also investigated. Differing from the nonionic surfactant C12E10, the distribution of TX114 is sensitive to the temperature, and it is observed that the TX114 concentration in the aqueous phase （Caq） does not depend on the initial TX114 concentration apparently at 45℃, and the Caq decreases with an increase of NazSO4 concentration. Low initial TX114 concentration in unclouded solutions, high Na2SO4 concentration, and temperature are suggested to control the surfactant loss in large-scale cloud point extraction applications.
文摘The microstructure of CdI2 thin film grown during vapor-phase deposition was investigated by scanning electron microscopy (SEM). The thin film deposited on Si crystal consists of numerous sunflower-like aggregates. These aggregates display well self-assembly characteristics. The size of Sunflower-like aggregates is between 12 and 44 μm. Each sunflower-like aggregate is surrounded with many adjacent wings-'petals'. The structure of central region of the 'sunflower' is obviously difFerent from that of the 'petal'. Electron spectroscopy for chemical analysis (ESCA) was employed in determining the chemical valence of the thin film. Self-organization efFect is used to explain the coring growth process of CdI2 thin film
基金the projects of National Natural Science Foundation of China(No.32301209)Key R&D Projects of Henan Province(Nos.231111312400 and 241111220400).
文摘Engineering hydrogels that resemble biological tissues of various lengths via conventional fabrication techniques remains challenging.Three-dimensional(3D)bioprinting has emerged as an advanced approach for constructing complex biomimetic 3D architectures,which are currently restricted by the limited number of available bioinks with high printability,biomimicry,biocompatibility,and proper mechanical properties.Inspired by ubiquitous coacervation phenomena in biology,we present a unique mineral-biopolymer coacervation strategy that enables the hierarchical assembly of nanoclay and recombinant human collagen(RHC).This system was observed to undergo a coacervation transition(liquid‒liquid phase separation)spontaneously.The formed dense phase separated from its supernatant is the coacervate of clay-RHC-rich complexes,where polymer chains are sandwiched between silicate layers.Molecular dynamics simulation was first used to verify and explore the coacervation process.Then,the coacervates were demonstrated to be potential bioinks that exhibited excellent self-supporting and shear-thinning viscoelastic properties.Through extrusion-based printing,the versatility of the bioink was demonstrated by reconstructing the key features of several biological tissues,including multilayered lattice,vascular,nose,and ear-like structures,without the need for precrosslinking operations or support baths.Furthermore,the printed scaffolds were cytocompatible,elicited minimal inflammatory responses,and promoted bone regeneration in calvarial defects.
基金supported by the National Natural Science Foundation of China(No.21973002).
文摘The liquid-liquid phase separation of biopolymers in living cells contains multiple interactions and occurs in a dynamic environment.Resolving the regulation mechanism is still a challenge.In this work,we designed a series of peptides(XXLY)_(6)SSSGSS and studied their complexation and coacervation behavior with single-stranded oligonucleotides.The“X”and“Y”are varied to combine known amounts of charged and non-charged amino acids,together with the introduction of secondary structures and pH responsiveness.Results show that the electrostatic interaction,which is described as charge density,controls both the strength of complexation and the degree of chain relaxation,and thus determines the growth and size of the coacervates.The hydrophobic interaction is prominent when the charges are neutralized.Interestingly,the secondary structures of peptides exhibit profound effect on the morphology of the phases,such as solid phase to liquid phase transition.Our study gains insight into the phase separation under physiological conditions.It is also helpful to create coacervates with desirable structures and functions.
基金financially supported by the National Key R&D Program of China(No.2022YFB3805103)the National Natural Science Foundation of China(No.22178139)。
文摘Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion failure.Thus,the design of adhesives for natural seawater represents challenges less resolved.Herein,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural seawater.By combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in seawater.The instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural seawater.The design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.
文摘Controlled delivery of proteins and other biologics is a growing medium of therapy for diseases previously untreatable.Here we report a self-assembling,tunable vesicle for the controlled delivery of growth factors and cytokines.Coacervate made of heparin and a biocompatible polycation,PEAD,forms the core of the vesicle;lipids form the membrane of the vesicle.We call this vesicle lipocoacervate(LipCo),which has a high affinity for growth factors and cytokines due to heparin.LipCo is a tunable protein delivery vehicle.The vesicle size is controlled through polymer and salt concentrations.Membrane functionalization enables potential for targeting capabilities with long-term storage through lyophilization.Importantly,the controlled delivery of therapeutics also avoids high toxicity to treated cells in vitro.Here we report on these key principles of LipCo assembly and design.
基金Chongqing Postdoctoral International Exchange Training Program(7820100997)Fundamental Research Funds for Central Universities(Nos.SWU-XDPY22010)+2 种基金National College Students Innovation and Entrepreneurship Training Program(202310635114)National Natural Science Foundation of China(No.81703424),Chongqing Graduate Student Research Innovation Project(CYB21121).
文摘Developing an oral in situ-forming hydrogel that targets the inflamed intestine to suppress bleeding ulcers and alleviate intestinal inflammation is crucial for effectively treating ulcerative colitis(UC).Here,inspired by sandcastle worm adhesives,we proposed a water-immiscible coacervate(EMNs-gel)with a programmed coacervate-to-hydrogel transition at inflammatory sites composed of dopa-rich silk fibroin matrix containing embedded inflammation-responsive core-shell nanoparticles.Driven by intestinal peristalsis,the EMNs-gel can be actuated forward and immediately transform into a hydrogel once contacting with the inflamed intestine to yield strong tissue adhesion,resulting from matrix metalloproteinases(MMPs)-triggered release of Fe3+from embedded nanoparticles and rearrangement of polymer network of EMNs-gel on inflamed intestine surfaces.Extensive in vitro experiments and in vivo UC models confirmed the preferential hydrogelation behavior of EMNs-gel to inflamed intestine surfaces,achieving highly effective hemostasis,and displaying an extended residence time(48 h).This innovative EMNs-gel provides a non-invasive solution that accurately suppresses severe bleeding and improves intestinal homeostasis in UC,showcasing great potential for clinical applications.
基金We are very much grateful to Dr.Beate Weidenthaler-Barth(De-partment of Dermatology,University Clinic Mainz)for the very expert histological analyses and the permission to include the images in this study.Moreover,we thank Mrs.Kerstin Bahr,Institute of Functional and Clinical Anatomy,University Medical Center,Mainz(Germany)for her continuous support.In addition,we are thankful to Mrs.Franziska S.Kranz(Medical Center of the Jo-hannes Gutenberg University,Mainz)for her important support.W.E.G.Müller is the holder of an ERC Advanced Investigator Grant(Grant No.268476)In addition,W.E.G.Müller has obtained three ERC-PoC grants(Si-Bone-PoC,Grant No.324564,MorphoVES-PoC,Grant No.662486,and ArthroDUR,Grant No.767234)+3 种基金In addition,this work was supported by grants from the European Commission(Grant Nos.604036 and 311848)the International Human Frontier Science Program,and the BiomaTiCS research initiative of the University Medical Center,Mainz.Further support came from the BMBF(Grant No.13GW0403A/B-SKIN-ENERGY)the BMWi(Grant No.ZF4294002AP9)the China National Key R&D Plan:China-German Cooperation(Grant No.2018YFE0194300).
文摘Insufficient metabolic energy,in the form of adenosine triphosphate(ATP),and bacterial infections are among the main causes for the development of chronic wounds.Previously we showed that the physi-ological inorganic polymer polyphosphate(polyP)massively accelerates wound healing both in animals(diabetic mice)and,when incorporated into mats,in patients with chronic wounds.Here,we focused on a hydrogel-based gel formulation,supplemented with both soluble sodium polyP(Na-polyP)and amor-phous calcium polyP nanoparticles(Ca-polyP-NP).Exposure of human epidermal keratinocytes to the gel caused a significant increase in extracellular ATP level,an effect that was even enhanced when Na-polyP was combined with Ca-polyP-NP.Furthermore,it is shown that the added polyP in the gel is converted into a coacervate,leading to encapsulation and killing of bacteria.The data on human chronic wounds showed that the administration of hydrogel leads to the complete closure of these wounds.Histological analysis of biopsies showed an increased granulation of the wounds and an enhanced microvessel forma-tion.The results indicate that the polyP hydrogel,due to its properties to entrap bacteria and generate metabolic energy,is a very promising formulation for a new therapy for chronic wounds.
基金the National Key Research and Development Program(2022YFB3804403)the Collaborative Research Fund from the Research Grants Council of Hong Kong(Project No.C5044-21G)+1 种基金the Research Grants Council of the Hong Kong Special Administration Region(project no.GRF/14202920,GRF/14204618,GRF/14108720,T13-402/17-N and AoE/M-402/20)National Natural Science Foundation of China(22205264).
文摘Protecting the skin from UV light irradiation in wet and underwater environments is challenging due to the weak adhesion of existing sunscreen materials but highly desired.Herein we report a polyethyleneimine/thioctic acid/titanium dioxide(PEI/TA/TiO_(2))coacervate-derived hydrogel with robust,asymmetric,and reversible wet bioadhesion and effective UV-light-shielding ability.The PEI/TA/TiO_(2)complex coacervate can be easily obtained by mixing a PEI solution and TA/TiO_(2)powder.The fluid PEI/TA/TiO_(2)coacervate deposited on wet skin can spread into surface irregularities and subsequently transform into a hydrogel with increased cohesion,thereby establishing interdigitated contact and adhesion between the bottom surface and skin.Meanwhile,the functional groups between the skin and hydrogel can form physical interactions to further enhance bioadhesion,whereas the limited movement of amine and carboxyl groups on the top hydrogel surface leads to low adhesion.Therefore,the coacervate-derived hydrogel exhibits asymmetric adhesiveness on the bottom and top surfaces.Moreover,the PEI/TA/TiO_(2)hydrogel formed on the skin could be easily removed using a NaHCO3 aqueous solution without inflicting damage.More importantly,the PEI/TA/TiO_(2)hydrogel can function as an effective sunscreen to block UV light and prevent UV-induced MMP-9 overexpression,inflammation,and DNA damage in animal skin.The advantages of PEI/TA/TiO_(2)coacervate-derived hydrogels include robust,asymmetric,and reversible wet bioadhesion,effective UV light-shielding ability,excellent biocompatibility,and easy preparation and usage,making them a promising bioadhesive to protect the skin from UV light-associated damage in wet and underwater environments.
基金supported by the National Natural Science Foundation of China(21735002,22177032,32101082)the Science Fund for Distinguished Young Scholars of Hunan Province(2021JJ10013)+1 种基金the Hunan Province Innovative Talent Funding for Postdoctoral Fellows(2021RC2059)the Postdoctoral Science Foundation of China(2021TQ0103,2021M690957).
文摘Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets are established as a model of artificial membraneless organelles in endothelial dysfunctional cells for the cascade enzymatic production of nitric oxide(NO) with a purpose of correcting cellular NO deficiency. We prepared the coacervate microdroplets via liquid-liquid phase separation of oppositely charged polyelectrolytes, in which glucose oxidase/horseradish peroxidase-mediated cascade reaction was compartmented. After the coacervate microdroplets were implanted in NO-deficient dysfunctional cells, the compartments maintained a phase-separated liquid droplet structure, which facilitated a significant enhancement of NO production in the dysfunctional cells. The recovery of NO production was further exploited to inhibit clot formation in blood plasma located in the cell suspension. This demonstrated a proof-of-concept design of artificial organelles in dysfunctional cells for cell repair and anticoagulation-related medical applications. Our results demonstrate an approach for the construction of coacervate droplets through phase separation for the generation of artificial membraneless organelles, which can be designed to provide an array of functionalities in living organisms that have the potential to be used in the field of cell engineering and medical therapy.
