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Collective behaviour in mixed populations of synthetic protocells is an unexplored area of bottom-up synthetic biology. The dynamics of a model protocell community is exploited to modulate the function and higher-order behaviour of mixed populations of bioinorganic protocells in response to a process of artificial phagocytosis. Enzyme-loaded silica colloidosomes are spontaneously engulfed by magnetic Pickering emulsion (MPE) droplets containing complementary enzyme substrates to initiate a range of processes within the host/guest protocells. Specifically, catalase, lipase, or alkaline phosphatase-filled colloidosomes are used to trigger phagocytosis-induced buoyancy, membrane reconstruction, or hydrogelation, respectively, within the MPE droplets. The results highlight the potential for exploiting surface-contact interactions between different membrane-bounded droplets to transfer and co-locate discrete chemical packages (artificial organelles) in communities of synthetic protocells., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Artificial cells have received much attention in recent years as cell mimics with typical biological functions that can be adapted for therapeutic and diagnostic applications, as well as having an unlimited supply. Although remarkable progress has been made to construct complex multifunctional artificial cells, there are still significant differences between artificial cells and natural cells. It is therefore important to understand the techniques and challenges for the fabrication of artificial cells and their applications for further technological advancement. The key concepts of top-down and bottom-up methods for preparing artificial cells are summarized, and the advantages and disadvantages of the bottom-up methods are compared and critically discussed in this review. Potential applications of artificial cells as drug carriers (microcapsules), as signaling regulators for coordinating cellular communication and as bioreactors for biomolecule fabrication, are further discussed. The challenges and future trends for the development of artificial cells simulating the real activities of natural cells are finally described.

Krill oil possesses strong antioxidant activity but has limited applications in the food industry due to its poor aqueous solubility, strong off‐flavours and susceptibility to oxidative degradation. This study was aimed to improve the colloidal and oxidative stability of krill oil via microencapsulation using spray drying. Whey protein isolate (WPI), maltodextrin (MD), carboxymethyl starch (CMS) and n‐octenylsuccinate starch (OSAS) were used as the microcapsule wall materials. The results showed that WPI+MD microcapsules had the optimum characterised properties compared to WPI+CMS and WPI+OSAS microcapsules. WPI+MD microcapsules possessed the highest encapsulation efficiency of 76.59%. The optimal air inlet temperature was 165°C, providing a high krill oil encapsulation efficiency and reducing concaveness on the microcapsule surfaces. Krill oil was distributed homogeneously inside the capsules and presented a good colloidal stability during an extended storage time. The antioxidant capacity against heat was simultaneously increased owing to the improved oxidative stability by microencapsulation. Consequently, this study provides useful guidelines for improving the stability and application of krill oil in the food industry. [ABSTRACT FROM AUTHOR]

A new type of concrete surface gel coating using thermosensitive fluorescent (TSF) microcapsules was proposed to monitor micro-cracks of cement-based materials. The gel materials can adhere other materials, and the incorporation of microcapsules into the gel coating can be cured on various structural surfaces. Zinc sulfide and phenyl acetate were encapsulated into a polymethyl methacrylate shell to prepare the TSF microcapsules by a solvent evaporation method. When micro-cracks are generated on the surface of the gel coating, the ruptured TSF microcapsules burst out, fill the damaged area, and then emit fluorescence after being excited at ambient temperature. It was found that the brightness of the fluorescence increased with increasing temperature from 80–110 °C. When the concentration of TSF microcapsules was 15% of the mass of the gel coating, the cement-based damage-sensing material had sufficient damage-indicating effects, and the fluorescence brightness of the crack location remained even after a long time. It is expected that this study will provide an effective and intuitive method for crack location detection of cement-based materials. [ABSTRACT FROM AUTHOR]

This study examined the effect of incorporation of spray dried nutmeg oleoresin on physical and functional properties of deep fried donuts. Donuts were made by sponge and dough method with the addition of 1% of microcapsules composed of two different wall material ratios (1:1 and 1:3) of gum arabic and sorghum starch (native and octenyl succinic anhydride). The results showed that addition of microcapsules did not significantly reduce the oil uptake in donuts. All the incorporated samples possessed better retention of bioactive compounds and having better antioxidant properties with high phenolic content. Nutmeg microcapsules composed of gum arabic and native starch in a proportion of 1:1 observed to have excellent textural, sensorial and physical properties as compared to control donut sample. The supplementation of GA:NAT (1:1) also showed high antioxidant value with higher total phenolic and flavonoid content. The study revealed that only 1% addition of nutmeg microcapsules in dough formulation can be improved the physical, textural and functional attributes of deep fried donuts. [ABSTRACT FROM AUTHOR]

There is an urgent need to reduce the environmental impacts of wool fabrics dyeing process while maintain its dyeing effects. Microcapsule technology is a potential option which could be used to move towards cleaner production process and to cope with ever-increasing demands for wool fiber dyeing efficiency. Reactive dyestuff microcapsules were prepared via reverse-phase evaporation methods and then auxiliary-free dye microcapsules were used to dye the wool fabrics. Transmission electron microscope images and fourier transform infrared showed that dye microcapsules possessed a spherical core–shell structure with a diameter of about 500 ± 5 nm. The processing factors were analyzed and optimized by using response surface methodology to improve the encapsulation rate. Higher fixation rate (80.13% vs. 72.03%) of dyed wool fabric, while lower absorbance of dyestuff (0.071 vs. 0.96), chemical oxygen demand (COD, 190 mg/L vs. 1395 mg/L) and biological oxygen demand (BOD5, 83.5 mg/L vs. 649.3 mg/L) of residual wastewater were observed by using microcapsule dyeing, compared with conventional dyeing process. In addition, the results also demonstrated that the filtrated wastewater of microcapsule dyeing can be recycled as dyebath to replace distill water. Thus, we innovatively produced a novel dye microcapsule for wool fabric dyeing application, advancing greatly in reducing the discharge of contaminants to environment, but also in economizing water and energy resources. [ABSTRACT FROM AUTHOR]

Abstract Essential oils are complex, volatile liquid mixtures that can be extracted from various parts of plants. Their main characteristics are strong fragrance and biological properties. Studying the characteristics of oils along with the possibility of an interaction with textiles creates new possible uses of this material. However, when oil is applied to a textile substrate, it is necessary to develop an oil release model, while most of the works only explore the application procedure and the fixed oil durability against washes. Thus, this work reports the mechanism and kinetics of controlled release of microencapsulated citronella oil from wool. The microencapsulation was done by complex coacervation with gelatin and gum Arabic biopolymers as shell materials. Optical microscopy, scanning electron microscopy and Fourier-transform infrared spectroscopy were used to confirm the encapsulation. The microcapsules were then supported by foulard in wool, fixed on fabrics and evaluated by attenuated total reflection Fourier-transform infrared spectroscopy. The controlled release of citronella from the microcapsules deposited on the fabric was studied in vitro. The microcapsules formed had a multi-core structure, and when applied to wool they showed diffusion by a Fickian mechanism in the first release stage and on the second stage changed to non-Fickian kinetics. The controlled release indicates that the textile structure influences the release model due to an interaction between fabric and water. Graphical abstract Unlabelled Image Highlights • The microcapsules formed by the biopolymers were polynuclear. • The encapsulated oil has more thermal stability, the microcapsule protects it. • The mechanism of controlled release presents two stages, Fickian and anomalous. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 is a pathogen, which can generate Shiga-like toxins (SLTs) and cause hemolytic-uremic syndrome. Foodborne illness outbreaks caused by E. coli O157:H7 have become a global issue. Since SLTs are quite toxic, effective medicines that can reduce the damage caused by SLTs should be explored. SLTs consist of a single A and five B subunits, which can inhibit ribosome activity for protein synthesis and bind with the cell membrane of host cells, respectively. Pigeon ovalbumin (POA), i.e. a glycoprotein, is abundant in pigeon egg white (PEW) proteins. The structure of POA contains Gal-α(1→4)-Gal-β(1→4)-GlcNAc ligands, which have binding affinity toward the B subunit in SLT type-1 (SLT-1B). POA immobilized gold nanoparticles (POA-Au NPs) can be generated by reacting PEW proteins with aqueous tetrachloroauric acid in one-pot. The generated POA-Au NPs have been demonstrated to have selective trapping-capacity toward SLT-1B previously. Herein, we explore that POA-Au NPs can be used as protective agents to neutralize the toxicity of SLT-1 in SLT-1-infected model cells. The results show that the cells can be completely rescued when a sufficient amount of POA-Au NPs is used to treat the SLT-1-infected cells within 1 h. [ABSTRACT FROM AUTHOR]

The traditional therapy of cancer has systemic side effects, and many cancers, such as human breast cancer and lung cancer easily metastasize to bones, leading to the formation of secondary tumours. This study was aimed at enhancing the anti-tumour effect of curcumin (CUR) and preventing tumour spread to the bone. A novel multifunctional redox-responsive and CD44 receptor targeting polymer-drug, poly alendronate-hyaluronan-S-S-curcumin copolymer (ALN-oHA-S-S-CUR) based CUR and alendronate (ALN) were synthesized successfully with the disulphide bond linker. The structure of ALN-oHA-S-S-CUR was characterized by 1H-NMR. The nanomedicine had natural anti-tumour drugs (CUR) as the hydrophobic kernel, and targeting CD44 receptor oligosaccharides of hyaluronan (oHA) and other anti-tumour drugs (ALN) as hydrophilic shell, named ALN-oHA-S-S-CUR conjugates, which could self-assemble into micelle-like nano-spheres in water via a dialysis method with hydrodynamic diameters of 179 ± 23 nm. Interestingly, the cur-loaded ALN-oHA-S-S-CUR micelles were stable in PBS but were capable of releasing the drug under the reducing environment. The rate of drug release was proportional to the GSH concentration. The uptake and cytotoxicity of micelles were higher in MDA-MB-231 cells than in MCF-7 cells because of a higher expression of the CD44 receptor in the former cell line. And compared to the cur-loaded oHA-CUR micelles, the cur-loaded ALN-oHA-S-S-CUR micelles had a good cellular uptake in 2D cancer cell and penetrability in 3D cancer cell spheroids. These results indicated the active targeting redox-sensitive micelles were promising as intracellular drug delivery systems for cancer treatment. [ABSTRACT FROM AUTHOR]

To protect sweet orange essential oil (SOEO) from volatilization and oxidation, and also to expand the range of application in physiology or medicine, beta‐cyclodextrin (β‐CD) is employed to develop SOEO microcapsules via an inclusion encapsulation method in this study. An optimal encapsulating condition obtained from response surface methodology (RSM) is an SOEO mass of 5.66 g, an encapsulating time of 3.24 h, and an encapsulating temperature of 53.7 °C, which provides the greatest encapsulation efficiency (EE) of 50.31%. Particle size and scanning electron microscope (SEM) reveal that rhombus, trapezoid, and parallelogram can be found in optimized microcapsule aggregates with a particle size of 1.34 ± 0.58 µm. Fourier transform infrared spectroscopy (FT‐IR) and differential scanning calorimetry (DSC) confirm the encapsulation of SOEO in β‐CD. Furthermore, the release study in vitro suggests that SOEO in microcapsules can be better released in simulated gastric fluid (SGF) than in simulated intestinal fluid, and the study in vivo suggests that, β‐CD might increase the solubility and bioavailability of SOEO. Thus, the microcapsules have potentials to be applied to the biomedical industry. Practical Applications: The optimal encapsulating condition is attained using RSM, and SOEO is capsuled to be a stable form in optimized microcapsules. The active ingredients of SOEO can be exerted fully by microcapsules. The microcapsules have excellent potentials for use as biological or pharmaceutical products. In this study, microcapsules of SOEO are developed using RSM. The physical and chemical characterizations of SOEO microcapsules are analyzed. The release behaviors in vitro and in vivo are also researched. Though these works, the microcapsules increase the solubility and bioavailability of SOEO, which has potentials for application in the biomedical industry. [ABSTRACT FROM AUTHOR]

Shrimp processing waste holds digestive proteases with a great potential to be used as feed supplement for Nile tilapia Oreochromis niloticus . In the present work, we characterize both sodium alginate (A) and sodium alginate-bentonite (AB) microcapsules to entrap enzymes obtained from Pleoticus muelleri processing waste. Also, we evaluate these encapsulation methods as a strategy to improve intestinal delivery of exogenous enzymes in O. niloticus in order to enhance their digestion process. The effects of different storage methods, in vitro simulation of gastric pH conditions and exposition to 40 °C were studied. In order to evaluate if microencapsulated shrimp enzymes are active when they reach fish gut, animals were exposed to three treatments: (1) fast, (2) diet and, (3) AB capsules + diet. Alginate capsules were more affected by different storage methods than alginate-bentonite ones. SEM images showed a correlation between decreased enzyme activity and capsule microstructure changes. The best method to store the AB beads is at −20 °C. After incubating for 7 h at 40 °C, we observed a notorious reduction in the enzyme activities of both microcapsules. On the other hand, at pH 3 both microcapsules prevented enzyme irreversible denaturalization and kept 100% of their activity. The overall results indicate that AB capsules are better vehicles to deliver shrimp enzymes in Nile tilapia. In the bioassay, we observed that when fish were fed with treatment 3, the alkaline protease activity in their intestines was 27% higher than that of the diet fish group. Thus, encapsulated shrimp enzymes have a great potential to be used as a feed supplement in fish nutrition. Further trials involving grow bioassays are needed to verify if this shrimp enzyme contained in AB capsules improve fish digestion, feed conversion, body weight and survival rate. [ABSTRACT FROM AUTHOR]

Objectives:The present study aimed to develop microparticles of phenolic hydroxyl derivative of carboxymethylcellulose (CMC-Ph) via Co-flow microfluidics technology and encapsulated gene-modified rat bone mesenchymal stem cells (BMSCs) for the detection of the growth factor release was controlled by Tet-on system. Meanwhile, we investigated the effect of the CMC-Ph microcapsules and Lentiviral transduction on osteogenesis of BMP2–BMSCs. Methods:The middle size of CMC-Ph microcapsules was prepared by optimized co-flow microfluidics through ejecting fluid CMC-Ph suspension (mixed with HRP) into co-flowing liquid paraffin which blends H2O2at priority. The Lentivirus-encoding hBMP-2 and Tet-On system were constructed and amplified by RT-PCR, then encapsulated in the microcapsules. The cellular viability of CMC-Ph microparticles was assessed by Live/dead staining and metabolic activity was estimated by colorimetric assay kit. In addition, BMP-2 secretion and kinetic studies were determined by ELISA, alkaline phosphatase (ALP) activity was evaluated using ALP assay kit, and ALP staining as well as mineral calcium deposition was detected by alizarin red S staining. Key findings:The diameter of CMC-Ph microparticles was controlled between 100 and 150 μm by altering the flow speed of liquid paraffin and then encapsulated bone morphogenetic protein 2 (BMP-2) gene modified BMSCs transduced by a lentiviral vector. Moreover, the mitochondrial activity of the encapsulated cells was maintained at least 24 d and BMP-2 protein secretion into the supernatant sustained for 35 d without significant loss of efficiency under the induction of the doxycycline. Furthermore, mineral deposition staining and ALP activity detection showed that encapsulated lentiviral-BMP2 transduced BMSCs possess more osteogenic differentiation potential than normal cells. Conclusions:Co-flow microfluidics and phenolic hydroxyl derivative of carboxymethylcellulose (CMC-Ph) provide a promising strategy for cell-enclosed microcapsules in combination with BMP-2 gene and Tet-on system modified BMSCs and then controlled BMP-2 protein released effectively as well as promoted the osteogenic differentiation of BMSCs. [ABSTRACT FROM PUBLISHER]

Membranes are important components in a number of systems, where separation and control of the flow of molecules is desirable. Controllable membranes represent an even more coveted and desirable entity and their development is considered to be the next step of development. Typically, membranes are considered on flat surfaces, but spherical capsules possess a perfect "infinite" or fully suspended membranes. Similarities and transitions between spherical and flat membranes are discussed, while applications of membranes are also emphasized. [ABSTRACT FROM AUTHOR]

A facile approach is described in this work to prepare spherical microcapsules of Palm stearine which are coated with hydrated layers of a food polymer-methylcellulose. These microcapsules were then used as structuring units to create unique hybrid oleogels where both crystalline fat particles and the hydrophilic polymer sheets contributed to the microstructure development. This approach could open-up new possibilities of utilizing a range of hydrophilic food polymers to improve the oil structuring properties of commonly used fat hard stocks. [ABSTRACT FROM AUTHOR]

Acaricidal nylon 66 fabrics (AN66Fs) grafted with clove oil-loaded microcapsules (COMCs) were developed against Dermatophagoides farina (D. gallinae). The average diameter was about 2.9 μm with a range of 100 nm-8.5 μm. COMCs carried clove oil loading of about 65 vol %. COMCs were chemically grafted to electrospun nylon nanofibers by the chemical reactions between -OH groups of COMCs and -COOH end groups of nylon fabrics to form ester linkages. AN66Fs had an effect on D. farinae depending on COMCs loadings. The increase in COMCs loading of AN66Fs from 5 to 15 wt % increased from 22% to 93% mortality against D. farinae within 72 h. However, AN66Fs containing over 20 wt % COMCs were more effective, showing up to 100% mortality within 24 h because the large amount of monoterpene alcohol, eugenol. This research suggests the use of clove oil and its major constituent eugenol as eco-friendly bioactive agents that can serve as a replacement for synthetic acaricides in controlling the population of D. farinae. [ABSTRACT FROM AUTHOR]

Probiotics possess potential therapeutic and preventative effects for various diseases and metabolic disorders. One important limitation for the oral delivery of probiotics is the harsh conditions of the upper gastrointestinal tract (GIT) which challenge bacterial viability and activity. One proposed method to surpass this obstacle is the use of microencapsulation to improve the delivery of bacterial cells to the lower GIT. The aim of this study is to use alginate-poly-L-lysine-alginate (APA) microcapsules to encapsulate Lactobacillus fermentum NCIMB 5221 and characterize its enzymatic activity and viability through a simulated GIT. This specific strain, in previous research, was characterized for its inherent ferulic acid esterase (FAE) activity which could prove beneficial in the development of a therapeutic for the treatment and prevention of cancers and metabolic disorders. Our findings demonstrate that the APA microcapsule does not slow the mass transfer of substrate into and that of the FA product out of the microcapsule, while also not impairing bacterial cell viability. The use of simulated gastrointestinal conditions led to a significant 2.5 log difference in viability between the free (1.10 × 104 ± 1.00 × 103 cfu/mL) and the microencapsulated (5.50 × 106 ± 1.00 × 105 cfu/mL) L. fermentum NCIMB 5221 following exposure. The work presented here suggests that APA microencapsulation can be used as an effective oral delivery method for L. fermentum NCIMB 5221, a FAE-active probiotic strain.

Alginate-galactosylated chitosan/polylysine (AGCP) microcapsules with excellent stability and high permeability were developed and employed in primary hepatocyte applications. The galactosylated chitosan (GC), synthesized via the covalent coupling of lactobionic acid (LA) with low molecular weight and water-soluble chitosan (CS), was ingeniously introduced into the core of alginate microcapsules by regulating the pH of gelling bath. The internal GC of the microcapsules simultaneously provided a large number of binding sites for the hepatocytes and further promoted the hepatocyte–matrix interactions via the recognition of asialoglycoprotein receptors (ASGPRs) on the hepatocyte surface, and afforded the AGCP microcapsules an excellent stability via the electrostatic interactions with alginate. As a consequence, primary hepatocytes in AGCP microcapsules demonstrated enhanced viability, urea synthesis, albumin secretion, and P-450 enzyme activity, showing great prospects for hepatocyte applications in microcapsule system. [ABSTRACT FROM AUTHOR]

Water-containing organic solutions are widespread reaction media in organic synthesis and catalysis. This type of multicomponent liquid system has a number of unique properties because of the tendency for water to self-organize in mixtures with other liquids. The characterization of these water domains is a challenging task because of their soft and dynamic nature. In the present study, the morphology and dynamics of micrometer- and nanometer-scale water-containing compartments in ionic liquids were directly observed by electron microscopy. A variety of morphologies, including isolated droplets, dense structures, aggregates, and 2D meshworks, have been experimentally detected and studied. Using the developed method, the impact of water on the acid-catalyzed biomass conversion reaction was studied at the microscopic level. The process that produced nanostructured domains in solution led to better yields and higher selectivities compared with reactions involving the bulk system. [ABSTRACT FROM AUTHOR]

Systems of motile microscopic particles can exhibit behaviors that resemble those of living microorganisms, including cooperative motion, self-organization, and adaptability to changing environments. Using mesoscale computational modeling, we design synthetic microswimmers and microcapsules that undergo controllable, self-propelled motion in solution. Stimuli-responsive hydrogels are used to actuate the microswimmers and to enable their navigation and chemotaxing behavior. The self-propelled motion of microcapsules on solid surfaces is achieved by the release of encapsulated solutes that alter the surface adhesiveness. These signaling solutes also enable interactions among multiple microcapsules that lead to complex, cooperative behavior. Our findings provide guidelines for creating microscopic devices and machines able to autonomously move and mimic the communication and chemotaxis of biological microorganisms. [ABSTRACT FROM AUTHOR]

Polyamide 6 microcapsules (PAMC) loaded with 2-10 wt% of different carbon allotropes: carbon black, multiwalled carbon nanotubes, carbon nanofibers and graphite were synthesized via activated anionic polymerization (AAROP) of ε-caprolactam in solution performed in the presence of the respective micro- or nanosized loads. The forming high-molecular weight microporous PAMC showed typical diameters of 15-35 #m, the filler particles being entrapped in the core as proven by microscopy methods. The melt processing of the loaded microcapsules produced PA6/C-filler hybrid thermoplastic composites with homogeneous distribution of one or two C-fillers even at loads of up to 10% without any functionalization. The crystalline structure of all PAMC and molded composites was studied by thermal and X-ray diffraction methods focusing on possible structure modification during the transition from PAMC to molded plates. Mechanical tests in tension and electrical conductivity measurements showed that transforming loaded PAMC into composites by melt processing could be a facile and rapid method to fabricate polyamide composites with improved mechanical performance and tailored electrical and dielectric properties. [ABSTRACT FROM AUTHOR]

Studies have shown that AITC can effectively control pathogenic fungi, which cause fruits and vegetables decay and rotting during storage. However, because of its strong irritant, AITC has not been conveniently used in fruits and vegetables preservation. Microencapsulation techniques may solve this problem. Up to 2% (w/v) gelatin and 2% (w/v) gum arabic (as wall material and materials), as well as AITC (as core material) were prepared used to form microcapsules with a ratio of 1:2 (the core material: to wall material). On the basis of the microcapsule option conditions, the AITC microcapsule encapsulation efficiency is above 90%, which can effectively control AITC release decrease irritant. Compared with control group, the storage time of the tomato of AITC microcapsule preservation was prolonged significantly, and the sensory quality of the tomato was better. Thus, the AITC microcapsule preservation has broad application prospects and development value prospects. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of H 2 O 2 –H 2 O filled poly(methyl methacrylate) (PMMA) microcapsules as potential candidates for controlled O 2 delivery. The microcapsules are prepared by a water-in-oil solvent emulsion and evaporation method. The results of this study describe the effect of process parameters on the characteristics of the microcapsules and on their in vitro performance. The size of the microcapsules, as determined from scanning electron microscopy, ranges from ∼5 to 30 μm and the size distribution is narrow. The microcapsules exhibit an internal morphology with entrapped H 2 O 2 –H 2 O droplets randomly distributed in the PMMA continuous phase. In vitro release studies of 4.5 wt% H 2 O 2 -loaded microcapsules show that ∼70% of the H 2 O 2 releases in 24 h. This corresponds to a total O 2 production of ∼12 cc/gram of dry microcapsules. Shelf-life studies show that the microcapsules retain ∼84 wt% of the initially loaded H 2 O 2 after nine months storage at 2–8 °C, which is an attractive feature for clinical applications. [ABSTRACT FROM AUTHOR]

The formation and characterization of a novel class of all-natural digestible microcapsules containing a liquid lipid core encapsulated by a water-insoluble protein shell with tunable thickness is demonstrated. As an example of a water-insoluble protein, zein is used-the protein of corn-which is an attractive biomaterial from a sustainable source. The microcapsules are prepared by a direct and simple method, based on the precipitation of protein from the continuous phase of an oil-in-(water/ethanol) emulsion onto the oil droplets without the need of any surfactant. The shell thickness can be controlled by the amount of precipitated protein. An in vitro digestion assay is performed to study the lipid hydrolysis and biodegradability. The rate of lipid hydrolysis and release of fatty acids are highly dependent on the protein shell thickness. All-natural edible microcapsules with controlled degradation under gastrointestinal conditions can enable new applications for oral delivery systems. They may further be used as a model system for controlled release studies of lipophilic compounds and could promote the sustainable use of underutilized water insoluble proteins as functional biomaterials. [ABSTRACT FROM AUTHOR]

Addition of microcapsules with a high dielectric constant and low specific heat capacity to a battered layer was designed to create a higher temperature in the crust than in the prefried fish nuggets to prevent the water vapor in the fish nuggets from migrating to the crust during microwave heating. Therefore, chitosan-silica hybrids and soybean oil were utilized to prepare the shell and core of the thermally stable microcapsules (MCCS), respectively. The MCCS were prepared by sol-gel coacervation from an oil-in-water emulsion. The sodium silicate was hydrolyzed and coacervated through polymerization for 24 h at pH 5. The zeta potential analysis indicated that chitosan with a positive charge and silica with a negative charge interacted through electrostatic attraction to form a hybrid shell. The volume mean particle size and encapsulation efficiency of the MCCS were 9.6 ± 0.2 μm and 75.6% ± 1.3%, respectively, when oil/chitosan = 0.2 and chitosan/silica = 0.5 (w/w). In addition to H-bonding and electrostatic attraction, Si-O-N bonds were formed between chitosan and silica. Dehydration of the bound water in the MCCS was observed in the range of 25 to 250 °C in the differential scanning calorimetry thermal analysis, with the lack of apparent thermal peaks indicating its high thermal stability. The decrease of force to cut the crust observed by texture analysis as well as the increase of hedonic score by consumer acceptance test revealed the addition of 1% MCCS significantly improved the crispness of the crust in the microwave-reheated nuggets. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we describe the delivery of plasmid DNA (pDNA) using silk fibroin (SF) layer-by-layer assembled microcapsules. Deposition of fluorescently labeled SF onto polystyrene (PS) template particles resulted in increasing fluorescence intensity and decreasing surface charge in correlation to SF layer number. After removal of the PS core, hollow, monodisperse, and structurally stable SF microcapsules of variable size and shell thickness were obtained. Plasmid DNA encoding for enhanced green fluorescent protein (eGFP) was loaded onto 1 or 4 μm capsules, either by incorporation of pDNA within the innermost layer of the shell or by adsorption to the microcapsules surface, and in vitro pDNA release, cytotoxicty and eGFP expression were studied. Sustained pDNA release over 3 days was observed using both loading techniques, being accelerated in the presence of protease. DNA loaded SF microcapsules resulted in efficient cell transfection along with low cytotoxicity after 3 days incubation compared to treatment with pDNA/branched polyethylenimine complexes. Among the tested conditions highest transfection efficiencies were achieved using 1 μm capsules where pDNA was adsorbed to the capsule surface. Our results suggest that SF microcapsules are suitable for the localized delivery of pDNA, combining low cytotoxicity and high transfection efficiency. [Copyright &y& Elsevier]

Highlights: [•] We have used PLGA and PLA with acid (PLA-COOH) and ester (PLA-COOR) terminations to formulate microcapsules containing perfluorohexane. PLGA led to nice core–shell microcapsules; PLA-COOH led to decentered microcapsules and big “eye” morphologies, and PLA-COOR induced the formation of “acorn” morphologies due to different interfacial properties. [•] The core–shell structure is the result of a significant adsorption of the polymer at the dichloromethane–water interface together with a good stability of the PFH droplet within the emulsion globule. [•] For PLGA-PFH and PLA-COOH microcapsules, the capsule's thickness-to-radius ratio can be controlled easily by varying the polymer to perfluorocarbon proportions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Carbon nanotubes was grafted and used to enhance the thermal conductivities of the microcapsules. [•] The average particle size of the prepared MicroPCMs/CNTs-SA is 0.1μm. [•] The thermal conductivity of MicroPCMs/CNTs-SA with 4% of CNTs increased by 79.2% compared with MicroPCMs. [•] MicroPCMs/CNTs-SA has better durability and thermal stability compared to the original MicroPCMs. [ABSTRACT FROM AUTHOR]

The aim of the study is to analyze the impact of application methods of microcapsules containing n-octadecane as phase change materials (M-PCM) on the thermal properties and air permeability of modified textile fabric. Polyester knitted fabric, printing, coating and padding methods and polymer pastes with 20wt.% of M-PCM were used. For the assessment of modification effects the differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were used. DSC analysis showed that the highest enthalpy of phase transitions has printed fabric and the lowest padded fabric. The widest range of phase transitions temperatures was observed for printed fabric, slightly narrower for coated fabric and the narrowest for padded fabric. SEM analysis showed differences in the morphology of modified fabrics depending on incorporation techniques, which are compatible with differences in air permeability results. M-PCM application techniques allow to regulate the thermal and air permeability properties of fabric. [ABSTRACT FROM AUTHOR]

In this study, a layer-by-layer (LbL) assembly (HEP/CHI) 5 microcapsule with doxorubicin hydrochloride (DOX) encapsulating inside was fabricated via alternatively depositing heparin (HEP) and chitosan (CHI) onto DOX-loaded CaCO 3 templates. The microcapsules were of stable architecture and had good dispersity in aqueous medium. Fluorescence observation showed that DOX distributed both in the wall and in the cavity of microcapsules, while HEP presented in the capsule wall. The release rate of DOX increased at acidic pH as compared with that at basic pH, suggesting a pH-responsive drug release behavior. The microcapsules with positively charged CHI lying on the outer layer could protect HEP from heparanase degradation and achieve intracellular co-delivery of both DOX and HEP. Thus, the DOX-loaded microcapsules could have improved inhibition activity against A549 cells by combining pharmacological actions of DOX and HEP. [ABSTRACT FROM AUTHOR]

Highlights: [•] Wall material of microcapsules is crucial for protecting fish oil from oxidation. [•] Hydrolysate of SPI–maltodextrin conjugate gives better stabilization. [•] Degree of hydrolysis strongly affects the emulsions and powders of fish oil. [•] Emulsions coated by limited hydrolyzed products showed better emulsion stability. [•] Powders coated by hydrolysates (DH 2.9%) showed better oxidative stability. [ABSTRACT FROM AUTHOR]

Introduction. The aim of this work is to determine the sign of the charge of microcapsules shells, containing oil composition and to estimate stability of microcapsules with different diameters in the electric field. Materials and methods. The microcapsules were prepared by complex coacervation method. Remains of electrolytes were removed by dialysis or electro-dialysis. Purified microcapsules were subjected to electrophoresis at 100-400 V/m. Polydispersity was determined by means of our own method. Results and discussion. Small microcapsules with protein-poliuronate shells moves from the cathode (-) to the anode (+) during electrophoresis. Microcapsules with a diameter much than 35µm are most susceptible to degradation in the cathode space, while remaining stable at low pH values at the anode surface. Conclusions. Gelatin-Alginat and Gelatin-Hyaluronat shells have a negative electric charge. Electrophoresis can be used to obtain required diameter of coacervate microcapsules. High stability of the microcapsules in the anode space (acid) confirms the validity of their introduction into fermented dairy products. [ABSTRACT FROM AUTHOR]

Microencapsulation is a process in which active substances are coated by extremely small capsules. It is a new technology that has been used in the cosmetics industry as well as in the pharmaceutical, agrochemical and food industries, being used in flavors, acids, oils, vitamins, microorganisms, among others. The success of this technology is due to the correct choice of the wall material, the core release form and the encapsulation method. Therefore, in this review, some relevant microencapsulation aspects, such as the capsule, wall material, core release forms, encapsulation methods and their use in food technology will be briefly discussed. [ABSTRACT FROM AUTHOR]

The biocompatible thiol-functionalized rGOSH/PMASH microcapsules encapsulating nerve growth factor (NGF) are arrayed onto a transparent and conductive substrate, i.e., indium tin oxide (ITO), to integrate electrically stimulated cellular differentiation, electrically controlled NGF release, and topographically rough nano-surfaces into a 3-D platform for nerve regeneration. The rGOSH/PMASH microcapsules with microscale topography function not only as an adhesive coating to promote the adhesion of PC12 cells but also as electroactive NGF-releasing electrodes that stimulate NGF release and accelerate the differentiation of PC12 cells during electrical stimulation. Once electrical treatment is applied, NGF release and electrically enhanced cellular differentiation lead to an obvious increase both in the percentage of cells with neurites and in the neurite length. This length can reach nearly 90 μm within 2 days of cell culture. The average neurite length is significantly increased (four-fold) after culture on the rGOSH/PMASH microcapsule substrate for 2 days compared with culture on a substrate without an rGOSH/PMASH coating. These multifunctional rGOSH/PMASH microcapsules may be used as potential 3-D patterned substrates for neural regeneration and neural prosthetics in tissue engineering applications. [ABSTRACT FROM AUTHOR]

The present study describes the development of multilayer microcapsules by 11 alternate additions of chitosan (Chi) and sodium dodecyl sulfate (SDS) in a combined emulsification and phase coacervation method based on ionic interactions. After an alkali treatment, microcapsules are applied on polyester (PET) fabric by a padding process to investigate their wash-durability on fabric. Air atmospheric plasma treatment is performed on PET fabric to modify the surface properties of the textiles. Zeta potential, X-ray photoelectron spectroscopy (XPS), wetting measurements, scanning electron microscopy (SEM), and atomic force microscopy (AFM) with surface roughness measurements are realized to characterize and determine wash durability of microcapsule samples onto PET. After alkali treatment, the microcapsules are selected for textile application because they are submicron sized with the desired morphology. The results obtained from various characterization techniques indicate that microcapsules are wash-durable on PET fabric pre activated by air plasma atmospheric as Chi based microcapsules can interact directly with PET by ionic interactions. [ABSTRACT FROM AUTHOR]

Scientific developments are in progress in order to create compressive fabric in the medical field. This study focused on the development of a compressive garment in polyamide designated for severe burns in terms of pressure and hydration release. The fabric was then enhanced by adding a moisturizing treatment. The improvement consisted of the impregnation of ethylcellulose microcapsules containing jojoba oil on the textile surface of compressive garment. The kinetic of release of this active ingredient from the microcapsules, as well as its diffusion through the skin, were assessed using thein vitroFranz diffusion cell system. The results showed a controlled release of jojoba oil over time. The amount of oil released during the experiments (168 h) and that which penetrated through the pig skin did not exceed 1% of the total amount of jojoba oil microencapsulated and impregnated on the surface of a compression garment. This study permitted to obtain a compressive garment which presents hydration properties. [ABSTRACT FROM PUBLISHER]

Abstract: This review addresses luminescent rare earth compounds assembled in microcapsules as well as in planar films fabricated by the layer-by-layer (LbL) technique, the Langmuir–Blodgett (LB) method and in self-assembled monolayers. Chemical precipitation, electrostatic, van der Waals interactions and covalent bonds are involved in the assembly of these compounds. Self-organized ring patterns of rare earth complexes in Langmuir monolayers and on planar surfaces with stripe patterns, as well as fluorescence enhancement due to donor–acceptor pairs, microcavities, enrichment of rare earth compounds, and shell protection against water are described. Recent information on the tuning of luminescence intensity and multicolors by the excitation wavelength and the ratio of rare earth ions, respectively, are also reviewed. Potential applications of luminescent rare earth complex assemblies serving as biological probes, temperature and gas sensors are pointed out. [Copyright &y& Elsevier]

Abstract: Microcapsules are reviewed with special emphasis on the relevance of controlled mechanical properties for functional aspects. At first, assembly strategies are presented that allow control over the decisive geometrical parameters, diameter and wall thickness, which both influence the capsule's mechanical performance. As one of the most powerful approaches the layer-by-layer technique is identified. Subsequently, ensemble and, in particular, single-capsule deformation techniques are discussed. The latter generally provide more in-depth information and cover the complete range of applicable forces from smaller than pN to N. In a theory chapter, we illustrate the physics of capsule deformation. The main focus is on thin shell theory, which provides a useful approximation for many deformation scenarios. Finally, we give an overview of applications and future perspectives where the specific design of mechanical properties turns microcapsules into (multi-)functional devices, enriching especially life sciences and material sciences. [Copyright &y& Elsevier]

Abstract: The encapsulation based technology permits long-term delivery of desired therapeutic products in local regions of body without the need of immunosuppressant drugs. In this study microcapsules composed of sericin and alginate micro bead as inner core and with an outer chitosan shell are prepared. This work is proposed for live cell encapsulation for potential therapeutic applications. The sericin protein is obtained from cocoons of non-mulberry silkworm Antheraea mylitta. The sericin–alginate micro beads are prepared via ionotropic gelation under high applied voltage. The beads further coated with chitosan and crosslinked with genipin. The microcapsules developed are nearly spherical in shape with smooth surface morphology. Alamar blue assay and confocal microscopy indicate high cell viability and uniform encapsulated cell distribution within the sericin–alginate–chitosan microcapsules indicating that the microcapsules maintain favourable microenvironment for the cells. The functional analysis of encapsulated cells demonstrates that the glucose consumption, urea secretion rate and intracellular albumin content increased in the microcapsules. The study suggests that the developed sericin–alginate–chitosan microcapsule contributes towards the development of cell encapsulation model. It also offers to generate enriched population of metabolically and functionally active cells for the future therapeutics especially for hepatocytes transplantation in acute liver failure. [Copyright &y& Elsevier]

Highlights: [•] Acridine orange and silica nanoparticles facilitated novel fluorescent hollow microcapsules are achieved. [•] Microcapsules do not limit intercalation of acridine orange with DNA. [•] AO exists in monomeric and aggregated form in the microcapsules. [•] It could sense DNA in the concentration range ngmL−1. [Copyright &y& Elsevier]

Highlights: [•] Microencapsulation of Schinus molle EO was useful for controlling the release of active components. [•] Microcapsules improved the insecticidal potential of Schinus molle EO. [•] The spray-drying technique applied was an efficient, inexpensive, and simple process. [•] The analytical method described herein could be useful for quality control of plant material and microcapsules. [ABSTRACT FROM AUTHOR]

A novel near-infrared light responsive microcapsule system, gold nanorod-covered DOX-loaded hollow 3 microcapsule (-HM-DOX) is developed for cancer therapy. The hollow 3 microcapsules were prepared based on the self-assembly between chitosan and sodium alginate on 3 particles via layer-by-layer technique, and then covered with gold nanorods to obtain the microcapsule system. Upon near-infrared (NIR) irradiation, microcapsule with gold nanorods can convert the absorbed NIR light into heat. Meanwhile, doxorubicin (DOX), a chemotherapy drug, is loaded into the microcapsule system via electrostatic adsorption for combined photothermal therapy and chemotherapy. Properties of -HM-DOX including grain diameter, optical spectra were characterized. Confocal fluorescence imaging was performed to observe the morphology of the capsules and existence of DOX in the core, confirming the successful loading of DOX. The release of DOX from the capsules under continuous NIR irradiation was investigated to evaluate the temperature responsiveness of -HM-DOX. Results indicate that -HM-DOX microcapsules possess uniform particle size and high light responsiveness. The combination of chemical and physical therapy of -HM-DOX features great potential as an adjuvant therapeutic alternative material for combined cancer therapy. [ABSTRACT FROM AUTHOR]

ABSTRACT The hydrolytic degradation and corresponding content release of capsules made of poly( d,l-lactic- co-glycolic acid) (PLGA) strongly depends on the composition and material properties of the initially applied copolymer. Consecutive or simultaneous release from capsule batches of combinable material compositions, therefore, offers high control over the bioavailability of an encapsulated drug. The keynote of this study was the creation of a superordinated database that addressed the correlation between the release kinetics of filling agents with different molecular weights from PLGA capsules of alternating composition. Fluorescein isothiocyanate (FITC)-dextran (with molecular weights of 4, 40, and 2000 kDa) was chosen as a model analyte, whereas the copolymers were taken from various 50:50 PLGA, 75:25 PLGA, and polylactide blends. With reference to recent publications, the capsule properties, such as the size, morphology, and encapsulation efficiency, were further modified during production. Hence, uniform microdisperse and polydisperse submicrometer nanocapsules were prepared by two different water-in-oil-in-water emulsification techniques, and additional effects on the size and morphology were achieved by capsule solidification in two different sodium salt buffers. The qualitative and quantitative examination of the physical capsule properties was performed by confocal laser scanning microscopy, scanning electron microscopy, and Coulter counting techniques to evaluate the capsule size distribution and the morphological appearance of the different batches. The corresponding agent release was quantified by fluorescence measurement of the FITC-dextran in the incubation media and by the direct measurement of the capsule brightness via fluorescence microscopy. In summary, the observed agent release showed a highly controllable flexibility depending on the PLGA blends, preparation methods, and molecular weight of the used filling substances. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4219-4228, 2013 [ABSTRACT FROM AUTHOR]

The design and characteristics of a micro-system for thermogravimetric analysis (TGA) in which heater, temperature sensor and mass sensor are integrated into a single device are presented. The system consists of a suspended cantilever that incorporates a microfabricated resistor, used as both heater and thermometer. A three-dimensional finite element analysis was used to define the structure parameters. TGA sensors were fabricated by standard microlithographic techniques and tested using milli-Q water and polyurethane microcapsule. The results demonstrated that our approach provides a faster and more sensitive TGA with respect to commercial systems. [ABSTRACT FROM AUTHOR]

The intrinsic advantages of microcapsules with regard to nanocapsules as intravenous drug carrier systems are still not fully exploited. Especially, in clinical situations where a long-term drug release within the vascular system is desired, if large amounts of drug have to be administered or if capillary leakage occurs, long-circulating microparticles may display a superior alternative to nanoparticles. Here, microcapsules were synthesised and parameters such as in vitro tendency of agglomeration, protein adsorption and in vivo performance were investigated. Biocompatible poly(ethylene glycol) (PEG)-coated poly( DL-lactide- co-glycolide) (PLGA) as wall material, solid and perfluorodecalin (PFD)-filled PEG-PLGA microcapsules (1.5 µm diameter) were manufactured by using a modified solvent evaporation method with either 1% poly(vinyl alcohol) (PVA) or 1.5% cholate as emulsifying agents. Compared to microcapsules manufactured with cholate, the protein adsorption (albumin and IgG) was clearly decreased and agglomeration of capsules was prevented, when PVA was used. The intravenous administration of these microcapsules, both solid and PFD-filled, in rats was successful and exhibited a circulatory half-life of about 1 h. Our data clearly demonstrate that PEG-PLGA microcapsules, manufactured by using PVA, are suitable biocompatible, long-circulating drug carriers, applicable for intravenous administration. [ABSTRACT FROM AUTHOR]

Highlights: [•] We introduce a facile route to synthesize ball-like polymer–inorganic patchy microcapsyles. [•] Sol–gel chemistry and phase separation were combined to generate the patchy capsules. [•] Patch size and shape can be tuned by tailoring the experimental parameters. [Copyright &y& Elsevier]

Abstract: The objective of this study was to evaluate encapsulated fatty matter using double emulsification and subsequent enzymatic gelation method using soy protein isolate cross-linked by transglutaminase. For this purpose, six extractions methods (acids, alkaline and enzymatic methods) were used. The extraction methods showed differences, total or partial extraction being observed when using the acid method, alkaline enzymatic method and the acid method with direct determination of the fatty acid composition. The presence of triglycerides and ethyl ester was investigated in the microcapsules by easy ambient sonic-spray ionization mass spectrometry (EASI-MS), high performance size exclusion chromatography (HPSEC) and the fatty acid composition as determined by gas chromatography (GC). The microcapsules were shown to contain 1.07g omega-3 fatty acids / 100g microcapsules. [Copyright &y& Elsevier]

We performed a series of trials to assess the effect of dietary supplementation with microencapsulated Enterococcus fecalis CG 1.0007 on growth performance, antioxidation activity, and intestinal microbiota in Arbor Acres broiler chickens ("broilers"). A total of 150 1 -d-old broilers were assigned randomly to 5 feeding treatments (a control group fed the basal diet, 3 groups fed the basal diet plus various concentrations of microencapsulated CG 1.0007, and 1 group fed the basal diet plus an antibiotic). Changes in important genera of intestinal bacteria were studied using 16S rRNA gene-based PCRdenaturing gradient gel electrophoresis (DGGE) profiling and real-time quantitative PCR analysis of fecal samples. During the course of the 42-d experimental period, ADG of the birds fed the high and intermediate concentrations of microcapsules were significantly greater (9.90 and 9.50%, respectively) and the ratios of feed to gain fed were significantly lower (4.40 and 4.00%, respectively) compared with the control group. The total antioxidant capacity and the content of malondialdehyde and superoxide dismutase in the microcapsule-treated groups showed significant changes in terms of antioxidation. The numbers of Lactobacillus and Bifidobacterium were significantly greater in the microcapsule-treated groups than in the control group. Cluster analysis indicated that the DGGE bacterial profiles were related to the feeding treatments and revealing the diversity and richness of the intestinal microbiota associated with supplementation of microcapsules. In summary, our results indicate that dietary addition of microencapsulated E. fecalis CG 1.0007 enhanced the growth performance of the broilers and improved their health. [ABSTRACT FROM AUTHOR]

Highlights: [•] Association of electrostatic force and chemical bonds. [•] A new finding of controlling the protrusion of nanorods from microcapsules. [•] Adjust the color of microcapsules by controlling the PySO3Na/PyCHO ratio. [•] A new to way sense environmental pH by the color change. [ABSTRACT FROM AUTHOR]

Highlights: [•] Chitosan–gelatin microcapsules were prepared by the complex coacervation. [•] Microcapsules were grafted onto the fabrics by the chemical crosslinking method. [•] The treated fabrics showed a strong antibacterial activity and washing durability. [Copyright &y& Elsevier]