Detection of phthalates migration from disposable tablewares to drinking water using hexafluoroisopropanol-induced catanionic surfactant coacervate extraction

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.

Coacervate Structures of CdI_2 Thin Film Grown during Phase Transformation

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

Polyelectrolyte Complexes and Coacervates Formed by De novo-Designed Peptides and Oligonucleotide

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.

Lipocoacervate,a tunable vesicle for protein delivery

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.

Cation-Dipole Interaction-Induced Coacervate Underwater Adhesives in Natural Seawater

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.

Bioinspired coacervate-based bioinks for construction of multiscale tissue engineering scaffolds

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.

Complex coacervate-derived hydrogel with asymmetric and reversible wet bioadhesion for preventing UV light-induced morbidities

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.

The correlation between thermally induced precipitateto-coacervate transition and glass transition in a polyelectrolyte-bolaamphiphile complex

The precipitate and the coacervate are two aggregated states in the polyelectrolyte complexes(PECs).The precipitate-to-coacervate transition and glass transition in PECs have been widely reported in the past.In many cases,the two phenomena are studied independently,although both of them are apparently affected by water and small ions.Here,utilizing a PEC system consisting of poly(acrylic acid)(PAA)and a cationic bolaamphiphile(DBON),we explore the states of PECs as a function of salt,temperature,and the molecular weight of PAAs.By a combination of microscopic observation,time-resolved fluorescence measurements,and differential scanning calorimetry,we identify salt/temperature driven precipitate-to-coacervate transitions of the complexes.The thermally induced morphology transformation from the precipitate to coacervate occurs around the glass transition temperature,indicating a strong correlation between the two processes.As the molecular weight of the PAA increases,the thermal transition temperature becomes higher.This finding offers new insights on the mechanistic interactions that dictate the aggregated states of PECs.Based on the photothermal effect of DBON,we also develop a UV light-induced strategy to mediate the precipitate-to-coacervate transition,providing a fantastic platform to create functional PEC materials.

Myocardial protection by heparin-based coacervate of FGF10

Heart disease is still the leading killer all around the world,and its incidence is expected to increase over the next decade.Previous reports have already shown the role of fibroblast growth factor10(FGF10)in alleviating heart diseases.However,FGF10 has not been used to treat heart diseases because the free protein has short half-life and low bioactivity.Here,an injectable coacervate was designed to protect growth factor from degradation during delivery and the effects of the FGF10 coacervate were studied using a mice acute myocardial infarction(MI)model.As shown in our echocardiographic results,a single injection of FGF10 coacervate effectively inhibited preserved cardiac contractibility and ventricular dilation when compared with free FGF10 and the saline treatment 6 weeks after MI.It is revealed in histological results that the MI induced myocardial inflammation and fibrosis was reduced after FGF10 coacervate treatment.Furthermore,FGF10 coacervate treatment could improve arterioles and capillaries stabilization through increasing the proliferation of endothelial and mural cells.However,with the same dosage,no statistically significant difference was shown between free FGF10,heparin+FGF10 and saline treatment,especially in long term.On another hand,FGF10 coacervate also increased the expression of cardiac-associated the mRNA(cTnT,Cx43 and α-SMA),angiogenic factors(Ang-1 and VEGFA)and decreased the level of inflammatory factor(tumor necrosis factor-α).The downstream signaling of the FGF10 was also investigated,with the western blot results showing that FGF10 coacervate activated the p-FGFR,PI3K/Akt and ERK1/2 pathways to a more proper level than free FGF10 or heparin+FGF10.In general,it is revealed in this research that one-time injection of FGF10 coacervate sufficiently attenuated MI induced injury when compared with an equal dose of free FGF10 or heparin+FGF10 injection.

Bio-inspired functional coacervates

Many functional coacervates have been identified in biological systems,which have attracted widespread interest.Coacervation is a liquid–liquid phase separation(LLPS)process in which a macromolecule-enriched liquid phase is formed together with a macromolecule-depleted phase.Bio-inspired coacervates possess excellent features such as underwater delivery,low interface energy,shear thinning,and excellent biocompatibility.They also serve as good delivery platforms for different types of molecules.In this review,we briefly discuss some important extracellular coacervate systems,including mussel adhesives,sandcastle worm glue,squid beak,and tropoelastin.We then provide an overview of the recent development of bio-inspired functional coacervates for various biomedical applications,including medical adhesives,drug delivery,and tissue engineering.Bio-inspired functional coacervates offer a promising material platform for developing new materials for biomedical applications.

A Multiresponsive Transformation between Surfactant-Based Coacervates and Vesicles

Low-molecular weight surfactants have significant potential as building blocks for prebiotic organization.However,reports about surfactant-based coacervates as protocell models capable of reversible transformation are scarce.Herein,we develop a simple system made of a surfactant(-)-N-dodecylN-methylephedrinium bromide(DMEB)and inorganic salts that is capable of spontaneous formation of vesicles,coacervates,and the reversible transformation between the two states.

用于实时皮肤创面愈合的超强工程化蛋白凝聚体黏合剂

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.

Surfactant Distribution in the Clouding of TX114

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.

Potentialities of the Poly(Aminoethyl Methacrylate) p(AMA) as Gelatin-Like Polymer in Complex Coacervation

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/m2.

Preparations and Properties of Perfume Microcapsules

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.

Preparation of Microcapsules and Half Life of the Kiwi Fruit Seed Oil by Complex Coacervation

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.

Whey Protein-Carboxymethylcellulose Obtained by Complex Coacervation as an Ingredient in Probiotic Fermented Milk

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.

Coacervation Microencapsulation of CaCO₃Particles with a Fluoropolymer by Pressure-induced Phase Separation of Supercritical Carbon Dioxide Solutions

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).

New insights into protein–polysaccharide complex coacervation:Dynamics,molecular parameters,and applications

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.

The physiological polyphosphate as a healing biomaterial for chronic wounds:Crucial roles of its antibacterial and unique metabolic energy supplying properties

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.