Search

In this work, it has been demonstrated for the first time that CeO 2 microcapsules with a unique vase-like morphology can be produced using a facile technique of spraying microdroplets of an aqueous Ce(NO 3) 3 solution onto the alkaline solution surface of Na 2 SO 4. It has been shown that layers of these microcapsules can be transferred from the solution surface to the substrate surface in two different ways, and depending on the transfer method, they can form ordered, oriented arrays on the substrate. A peculiarity of one of these arrays is that in the layer on the substrate surface, almost all of the microcapsules are oriented with the hole in the wall toward the substrate, while in the other type of array they are oriented in the opposite direction. The structural and chemical characteristics of these microcapsules were investigated using SEM, STEM, HRTEM, EDX, XRD, UV–Vis DR, Raman and FT-IR spectroscopy. It has been established that the walls of these microcapsules are approximately 50–100 nm thick and consist of CeO 2 nanocrystals with a size of 2–5 nm with fcc crystal structure of fluorite. On the surface of these nanocrystals, there are adsorbed NO 3 − and SO 4 2− anions that can be removed by heating the samples to temperatures of 400 °C and 600 °C, respectively. The use of a solution containing a mixture of Ce(III) and Eu(III) nitrates as a reagent in the synthesis process allows for the production of microcapsules whose walls consist of CeO 2 nanocrystals that were doped with Eu(III) cations. These microcapsules display photoluminescence bands in the visible range attributed to 5D 0 –7F J transitions in europium ions upon λ ex = 330 nm and 462 nm. It is proposed that this technique for synthesizing microcapsules could be used to produce microcapsules based on CeO 2 nanoparticles doped with a wide range of metal cations. [Display omitted] [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Chenpi extract (CPE) is rich in polyphenols, flavonoids, and volatile flavor compounds, and possesses numerous healthy biological effects. However, the low stability and bioaccessibility of CPE significantly limits its application in food development.In this study, CPE microcapsules were prepared using soybean oligopeptide (SOP), maltodextrin (MD), soybean protein isolate (SPI), and citrus insoluble dietary fiber (CIDF) as the encapsulants. The successful encapsulation and thermal stability of the CPE microcapsules were confirmed through structural, interaction characterization, and thermal analyses. Soybean oligopeptide encapsulated 97.89% of the total flavonoids and 95.97% of the total polyphenols in CPE, which was significantly higher than the other three materials (MD, SPI, and CIDF). Soybean oligopeptide also showed good retention capacity for volatile flavor compounds in CPE, especially d‐limonene (47.67%), γ‐terpinene (49.65%), n‐octanal (57.38%), and β‐Myrcene (44.65%). The in vitro digestion results showed that the CPE loaded by SOP was more stable during simulated digestion compared with the CPE loaded by the other three materials. The bioaccessibility of total flavonoids and total polyphenols in CP‐SOP was 96.64% and 88.95%, respectively.Overall, these results highlight that SOP is a better carrier for CPE microcapsules, and the distinct characteristics of SOP could significantly improve the quality of Chenpi‐related functional food. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Probiotics have gained significant attention owing to their roles in regulating human health. Recently, spray drying has been considered as a promising technique to produce probiotic powders due to its advantages of high efficiency, cost-saving, and good powder properties. However, the severe environmental conditions from drying and digestion can significantly reduce cell viability, resulting in poor bioaccessibility and bioavailability of live cells. Therefore, there is a need to develop effective targeted delivery systems using spray drying to protect bacteria and to maintain their physiological functions in the targeted sites. This review highlights recent studies about spray-dried targeted delivery vehicles for probiotics, focusing on key strategies to protect bacteria when encountering external stresses, the formation mechanism of particles, the targeted release and colonization mechanisms of live cells in particles with different structures. Advances in the targeted delivery of live probiotics via spray-dried vehicles are still in their early stages. To increase the possibilities for industrialization and commercialization, functional improvement of microcapsules in terms of protection, targeted release, and colonization of bacteria, as well as the effect of spray drying on bacterial physiological functions in the host, need to be further investigated. [ABSTRACT FROM AUTHOR]

This work evaluates the effect of poly(urea‐formaldehyde) (PUF) microcapsules filled with aminated polydimethylsiloxane (PDMS‐a), a self‐healing agent, on the tensile properties of epoxy composites reinforced with graphene nanoplatelets (GNP). The microcapsules are produced by interfacial polymerization and later are infiltrated with the healing agent (PDMS‐a). GNP are dispersed in epoxy resin using sonication, followed by the addition of hollow or filled PUF microcapsules to the system, using mechanical stirring, just before the addition of the curing agent (hardener). The mixture is then cast in soft molds to produce specimens for tensile tests. The results show that the presence of 1 wt% GNP changes the properties of the composites with an improvement in tensile strength and modulus, which achieves 37.4 MPa and 2.8 GPa, respectively, in comparison with neat epoxy and specimens containing just microcapsules. The addition of 2 wt% GNP, however, impairs these properties, with tensile strength and Young's modulus decreasing to 24.9 MPa and 2.3 GPa, due to the presence of GNP agglomerates. The presence of the microcapsules, however, decreases the immediate (no self‐healing) tensile performance of the composites. [ABSTRACT FROM AUTHOR]

In order to improve the utilization rate of solar energy, a new type of photo-thermal phase-change microcapsules PCM@SA@PDA was successfully prepared with n-docosane (C-22) as core material and sodium alginate (SA) and polydopamine (PDA) as composite wall material. Here, SA capsules were formed by cross-linking of metal ions to envelop and prevent the leakage of melted C-22 (PCM@SA). Dopamine was self-polymerized on the surface of PCM@SA microcapsule; thus, efficient light absorption was achieved for photo-thermal transformation. The chemical structure, thermal properties, light absorption properties and photo-thermal conversion properties of the prepared microcapsules were analyzed and characterized. Based on the study of the effect of different contents of C-22 core materials on the thermal storage performance of PCM@SA, the optimal addition amount of C-22 was determined to prepare photo-thermal phase-change microcapsules. Compared with the PCM@SA, the photo-thermal phase-change microcapsule PCM@SA@PDA still showed good stability and heat storage performance. Their melting heat enthalpy was about 152.5 J g−1, and they also showed better photo-thermal conversion performance. Combining C-22, SA and PDA to prepare photo-thermal conversion phase change energy storage materials, the method was characterized by strong adaptability, simple operation, low production cost and high economic benefits, which could not only further improve the stability of the composite material, but also increase the photo-thermal conversion efficiency of the system. Therefore, this composite material integrating active light absorption, conversion and storage functions would have higher solar energy utilization rate and broader application prospect. [ABSTRACT FROM AUTHOR]

The use of microcapsules as preservative vessels for healing materials has led to a great revolution in the repair of materials. Microcapsules have been used in medicine, agriculture, metallurgy and mechanics. In civil engineering applications, microcapsules are usually used for the self-healing of concrete, asphalt and cementitious materials. Concrete and cement are widely used in civil engineering and are the predominant construction materials worldwide. The objective of this study was to design and produce urea–formaldehyde microcapsules for the recovery of reactive powder concrete (RPC). It was found that RPC specimens with and without microcapsules exhibited different behaviours. All of the RPC specimens containing microcapsules were found to have lower strengths than specimens without microcapsules. The smallest reductions in compressive strength were observed in specimens with a microcapsule content of 4–6% by weight of cement. The healing ratio of compressive strength increased with an increase in the weight percentage of microcapsules. Scanning electron microscopy and energy-dispersive spectroscopy were used to observe the process of crack healing, and the results showed that the cracks were filled with healing products. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Local Khulays clay was modified to prepare polystyrene clay nanocomposite (PCN) coatings on carbon steel. The PCN coatings were added to microcapsules (MCs) loaded with the corrosion inhibitor PCN(MC). The microcapsules were prepared by the encapsulation of rare-earth metal Ce+3 ions and isobutyl silanol into polystyrene via the double emulsion solvent evaporation (DESE) technique. From characterization techniques, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) with EDX. SEM and FT-IR confirmed the success of the preparation of the PCN(MC). Nanoindentation tests were performed on the thin-film samples. A significant reduction in both the hardness and the reduced modulus was observed for the PCN film compared to the PS film. Electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) all showed an enhanced protection efficiency (%PE) of 3% PCN(MC) over 3% PCN at high temperatures and at different times. The smart coatings were proven by applying the thermal and the mechanical triggers for the 3% PCN(MC) coating. The mechanism of the release of inhibitors was discussed. The self-healing properties of 3% PCN(MC) were evaluated. The enhanced properties of the developed PCN(MC) coatings make them attractive for potential applications in the oil and other industries. [ABSTRACT FROM AUTHOR]

This study focuses on the selection and evaluation of a kinetic model for the release of vitamin C from different delivery systems, including microcapsules, hydrogels, and a hybrid system combining both. The microcapsules were synthesized from a 2% sodium alginate solution and with vitamin C incorporated in selected formulations. Hydrogels were obtained through photopolymerization using poly(ethylene glycol) diacrylate and polyvinyl alcohol, with and without the addition of vitamin C. The hybrid system incorporated the vitamin C-containing microcapsules within the hydrogel matrix. Physicochemical properties, such as density, porosity, and water vapor transmission rate (WVTR), were evaluated. Kinetic studies of vitamin C release were conducted under dynamic and static conditions, and the experimental data were fitted to six different kinetic models: zero-order, first-order, second-order, Higuchi, Korsmeyer–Peppas, and Hixson–Crowell. The Higuchi and Korsmeyer–Peppas models provided the best fit for most systems, indicating that the release is predominantly controlled by diffusion and, in dynamic conditions, swelling of the matrix. The hybrid system, while exhibiting slower release than the microcapsules and hydrogel alone, demonstrated more controlled and sustained release, which is advantageous for applications requiring prolonged action. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) is a type of probiotic that may benefit intestinal health. Recent advances in nanoencapsulation provide an effective strategy to protect them from harsh conditions via surface functionalization coating techniques. Herein, the categories and features of applicable encapsulation methods are compared to highlight the significant role of nanoencapsulation. Commonly used food-grade biopolymers (polysaccharides and protein) and nanomaterials (nanocellulose and starch nanoparticles) are summarized along with their characteristics and advances to demonstrate enhanced combination effects in LAB co-encapsulation. Nanocoating for LAB provides an integrity dense or smooth layer attributed to the cross-linking and assembly of the protectant. The synergism of multiple chemical forces allows for the formation of subtle coatings, including electrostatic attractions, hydrophobic interactions, π–π, and metallic bonds. Multilayer shells have stable physical transition properties that could increase the space between the probiotic cells and the outer environment, thus delaying the microcapsules burst time in the gut. Probiotic delivery stability can be promoted by enhancing the thickness of the encapsulated layer and nanoparticle binding. Maintenance of benefits and minimization of nanotoxicity are desirable, and green synthesized nanoparticles are emerging. Future trends include optimized formulation, especially using biocompatible materials, protein or plant-based materials, and material modification. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nano-zirconium oxide particles were immobilized into chitosan via electrospraying technique to obtain organic-inorganic hybrid microcapsules (CZ) serving as self-healing anticorrosion materials for the enhancement of epoxy coating. Assessment of produced materials through adequate characterizations revealed hybrid microcapsules possessed spherical morphology with a mean size of 300 μm and thermal stability at 700oC up to ~ 50%. Subsequently, CZ was incorporated into an epoxy coating matrix to develop a self-healing coating, CZPx, for carbon steel protection. SEM and EIS analysis of scratched CZPx coating at 14 days of immersion in a corrosive medium confirmed the self-healing and anticorrosion capabilities of the coating with the impedance at the coating-substrate interface increasing from 2.01 × 106 to 1.22 × 107 (ohm cm2) between the 7th to 14th day of immersion. The barrier property of CZPx was determined through capacitance (CPEdl) to be higher than neat epoxy coating with a stronger impedance to the ingression of corrosion agents after the 14th day of immersion. Due to the unique feature of prepared CZ that allows their absorption of corrosion ions and formation of cross-linkages, self-healing was triggered upon the introduction of defects. The inhibitive nature of CZ provided superior anticorrosion properties to epoxy coating. [ABSTRACT FROM AUTHOR]

Perylenediimide‐chitosan/γ‐poly (glutamic acid) microcapsules sizing (PDI‐CS/γ‐PGA) core–shell microcapsule is designed and used to establish a novel interphase in carbon fiber/epoxy (CF/EP) composite, and the interfacial property, as well as the damage self‐reporting of the composite, is compared with desized carbon fiber (CF‐desized)/EP and commercial carbon fiber (CF‐COM)/EP composite. The ruptured PDI‐CS/γ‐PGA microcapsule exhibits strong "turn‐on" green fluorescence from the released PDI upon mechanical stimuli. The anchoring of PDI‐CS/γ‐PGA microcapsule on carbon fiber with PDI‐CS/γ‐PGA microcapsules sizing (CF@PDI‐CS/γ‐PGA) surface results in increased chemical activity and roughness, exhibiting a weak green fluorescence signal instead of non‐fluorescence on CF‐desized and CF‐COM surface. The transverse fiber bundle tensile (TFBT) strength of CF@PDI‐CS/γ‐PGA composite is 80.97% and 31.09% higher than those of CF‐desized/EP and CF‐COM/EP composite, which is attributed to the mechanical interlocking and chemical bonding interaction between carbon fiber and epoxy matrix by introducing PDI‐CS/γ‐PGA microcapsule with spherular structure and active groups. After microdroplet testing, the strong "turn‐on" green fluorescence signal of the released PDI from the microcapsules is detected in the interfacial debonding regions, realizing the microscopic damage self‐reporting of CF@PDI‐CS/γ‐PGA composite. [ABSTRACT FROM AUTHOR]

Background/Objectives: This study focuses on the development and evaluation of novel alginate–poly[2-(methacryloyloxy)ethyl]trimethylammonium chloride (PMETAC) microcapsules for encapsulating pancreatic islets to address insulin deficiency in diabetes. Methods: In previous research, we fabricated and characterized PMETAC microcapsules, evaluating their stability and permeability in vitro. This study further probes the capsules in vivo, focusing on the functional activity of the encapsulated islets post-transplantation, their viability extension, and the assessment of the immunoprotective, antifibrotic properties, and biostability of the capsules. Results: Rabbit-derived islets were encapsulated and transplanted into diabetic rats. The encapsulated islets maintained insulin secretion for up to 90 days, significantly longer than non-encapsulated ones, which ceased functioning after 7 days. Histological analysis demonstrated high biocompatibility of the PMETAC coating, resulting in minimal fibrotic overgrowth around the capsules. Conclusions: The study highlights the critical role of immunoprotection and the tendency to reduce fibrosis in prolonging islet function. These findings suggest that PMETAC-coated capsules offer a promising solution for cell-based therapies in diabetes by improving graft longevity and reducing fibrotic overgrowth. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to fabricating thinner shells and significantly enhancing the fracture strength of melamine-urea-formaldehyde (M-U-F) microcapsules reinforced with multi-walled carbon nanotubes (MWCNTs). Unlike previous studies that primarily focused on single-walled carbon nanotubes (SWCNTs) or MWCNTs in polyurea-formaldehyde (PUF) shells, this research advances microcapsule technology by exploring MWCNT reinforcement in M-U-F shells. We employed a dual experimental-numerical approach, combining the precision of micro-compression tests with the predictive capabilities of finite element analysis (FEA) to determine the elastic modulus of MWCNT-reinforced M-U-F microcapsules. This method offers new insights into the mechanical behavior of these microcapsules. Our findings indicate an 8.8% increase in fracture load and a 14.6% reduction in fracture displacement for MWCNT-reinforced microcapsules compared to conventional M-U-F microcapsules. Additionally, FEA confirmed the results of the micro-compression tests, showing that MWCNT-reinforced microcapsules had the best correlation with an elastic modulus of 4.00 GPa. Conventional M-U-F microcapsules corresponded to an elastic modulus of 2.25 GPa. These results provide a comprehensive understanding of how nano-reinforcement influences the structural properties of thin-walled microcapsules, with potential applications in composite damage repair and beyond. [ABSTRACT FROM AUTHOR]

Traditional anticorrosion coatings often suffer from reduced effectiveness or even complete failure due to the formation of microcracks. Isophorone diisocyanate (IPDI) can form a polyurea structure without a catalyst in the presence of water, which can protect the underlying metal from corrosion. In this study, an anticorrosion coating with self-healing properties was developed by incorporating microcapsules containing IPDI into the coating formulation. Silica-based self-healing microcapsules were synthesized via interfacial polymerization, using tetraethyl orthosilicate as the precursor and IPDI as the core material. The effects of core-to-wall ratio, reaction temperature, different emulsifiers, and emulsifier ratios on the microcapsule properties were investigated. The results demonstrated that microcapsules prepared using a composite emulsifier system of cetyltrimethylammonium bromide (CTAB) and OP-10 at a 1:1 ratio, with a core-to-wall ratio of 1:1, and a reaction temperature of 75°C, exhibited a smooth surface, spherical shape, and excellent encapsulation efficiency. The maximum core content achieved was 81.2 wt%. An epoxy coating embedded with these self-healing microcapsules was subjected to scratching damage. After applying water to the surface and allowing it to stand for 2 days, the scratches healed, and the steel plate surface remained free from corrosion, indicating excellent self-healing performance. [ABSTRACT FROM AUTHOR]

Limestone calcined clay cement (LC3), enhanced through reactions with volcanic ash and the interaction between limestone and clay, significantly improves the performance of cementitious materials. It has the potential to cut CO2 emissions by up to 30% and energy consumption in cement manufacture by 15% to 20%, providing a promising prospect for the large-scale production of low-carbon cement with a lower environmental effect. To effectively manufacture LC3 concrete, this study utilized limestone (15%), calcined clay (30%), and gypsum (5%) as supplementary cementitious materials (SCMs), replacing 50% of ordinary Portland cement (OPC). However, in regions abundant in sulfate, sulfate attack can cause interior cracking of concrete, reducing the longevity of the building. To address this issue, microcapsules containing microcrystalline wax, ceresine wax, and nano-CaCO3 encapsulated in epoxy resin were prepared and successfully incorporated into LC3 concrete. Sulfate resistance tests were conducted through sulfate dry–wet cycles, comparing samples with and without microcapsules. The findings revealed that the initial mechanical and permeability properties of LC3 concrete did not significantly differ from OPC concrete. LC3 concrete with added microcapsules (SP4) exhibited enhanced resistance to sulfate attack, reducing mass loss and compressive strength degradation. SEM images displayed a mesh-like structure of repair products in SP4. After 14 days of self-repair, SP4 exhibited a 44.2% harmful pore ratio, 98.1% compressive strength retention, 88.7% chloride ion diffusion coefficient retention, 91.12 mV maximum amplitude, and 9.14 mV maximum frequency amplitude. The experimental results indicate that the presence of microcapsules enhances the sulfate attack self-healing performance of LC3 concrete. [ABSTRACT FROM AUTHOR]

Phase change energy storage microcapsules were synthesized in situ by using melamine-formaldehyde–urea co-condensation resin (MUF) as wall material, n-octadecane (C18) as core material and styryl-maleic anhydride copolymer (SMA) as emulsifier. Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry and thermogravimetric analysis were used to study the effects of emulsifier type, emulsifier dosage, core–wall ratio and pH on the morphology and thermal properties of microcapsules. The results show that the pH of core material and the ratio of core to wall have a great influence on the performance of microcapsules. SMA emulsifiers and MUF are suitable for the encapsulation of C18. When the pH is 4.5 and the core–wall ratio is 2/1, the latent heat and encapsulation efficiency of phase transition reaches 207.3 J g−1 and 84.7%, respectively. The prepared phase-change microcapsules also have good shape stability and thermal stability. [ABSTRACT FROM AUTHOR]

More than half of the global population is unable to consume dairy products due to lactose intolerance (hypolactasia). Current enzyme replacement therapy methods are insufficiently effective as a therapeutic approach to treating lactose intolerance. The encapsulation of β-galactosidase in polyelectrolyte microcapsules by using the layer-by-layer method could be a possible solution to this problem. In this study, adsorption and co-precipitation methods were employed for encapsulating β-galactosidase in polyelectrolyte microcapsules composed of (polyallylamine /polystyrene sulphonate)₃. As a result, the co-precipitation method was chosen for β-galactosidase encapsulation. The adsorption method permits to encapsulate six times less enzyme compared with the co-precipitation method; the β-galactosidase encapsulated via the co-precipitation method released no more than 20% of the initially encapsulated enzyme in pH 2 or 1 M NaCl solutions. In contrast, when using the sorption method, about 100% of the initially encapsulated enzyme was released from the microcapsules under the conditions described above. The co-precipitation method effectively prevents the complete loss of enzyme activity after 2 h of incubation in a solution with pH 2 while also alleviating the adverse effects of ionic strength. Consequently, the encapsulated form of β-galactosidase shows promise as a potential therapeutic agent for enzyme replacement therapy in the treatment of hypolactasia. [ABSTRACT FROM AUTHOR]

The addition of microcapsules (MCs) to a polymer matrix has been gaining attention because it facilitates the attainment of composite materials with better mechanical, chemical and functional properties that enhance its tribological properties. In this work, poly (urea formaldehyde) (PUF) microcapsules filled with castor oil were synthesized using an in situ polymerization method and then added to the epoxy matrix at mass percentages of 2.5%, 5% and 10%. Spherical microcapsules were obtained with the desired composition, confirmed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) images. The surface of the composites was analyzed using the roughness parameters Ra, Rq, Rz, Rsk and Rku. The preliminary tribological properties were evaluated using tests with a pin-on-disk configuration. After the tribological tests, the wear track was characterized using SEM images. There was a reduction of approximately 50% in the coefficient of friction of the composites studied and the specimen with 2.5% microcapsules had the best self-lubricating performance, considering the characterizations of roughness and track sinking. [ABSTRACT FROM AUTHOR]

[Display omitted] Phase change materials (PCMs) can store and release latent heat under the designed phased change temperature and have received substantial interest for energy conservation and thermal control purposes. The use of PCMs in the construction of constant temperature buildings can improve the comfortable environment and save more energy. However, the leakage of PCMs during phase change process limits the application of PCMs. In this paper, a series of PCMs microcapsules with controllable core numbers is synthesized with paraffin (37 ℃) as the core and cross-linked chitosan as the wall. The single-core phase-change microcapsules (S−PCM) and multicore phase-change microcapsules (M−PCM) were prepared by adjusting the preparation condition. The latent heat of S−PCM and M−PCM are 61.4 mJ mg−1 and 50.1 mJ mg−1, respectively. The S-PCM and M−PCM display good stability without paraffin leakage. In addition, the composite blocks of gypsum and S−PCM (GSCM) and M−PCM (GMCM) were prepared and the thermoregulatory effection was investigated, where the surface temperature of GSCM was 5–10 ℃ lower than that of pure gypsum block. PCMs may also have broad application space in electronics, cold chain, and other industries. [ABSTRACT FROM AUTHOR]

[Display omitted] Optical information encryption with high encoding capacities can significantly boost the security level of anti-counterfeiting in the scenario of guaranteeing the authenticity of a wide scope of common and luxury goods. In this work, a novel counterfeiting material with high-degree complexity is fabricated by microencapsulating cholesteric liquid crystals and triplet–triplet annihilation upconversion fluorophores to integrate structural coloration with fluorescence and upconversion photoluminescence. Moreover, the multimode security ink presents tailorable optical behaviors and programmable abilities on flexible substrates by various printing techniques, which offers distinct information encryption under different optical modes. The advanced strategy provides a practical versatile platform for high-secure-level multimode optical inks with largely enhanced encoding capacities, programmability, printability, and cost-effectiveness, which manifests enormous potentials for information encryption and anti-counterfeiting technology. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND RESULTS CONCLUSION Sea buckthorn (Hippophae rhamnoides L.) pulp oil is rich in functional components; however, low water solubility and stability limit its applications. This study fabricated sea buckthorn pulp oil microcapsules using whey protein isolate (WPI), soy protein isolate (SPI), sodium caseinate (NaCN), gum arabic (GA), starch sodium octenylsuccinate (OSAS) and SPI mixed with chitosan (CHI). The influences of these wall materials on physicochemical properties, release behavior and digestibility were explored.Protein‐based wall materials (WPI, NaCN, SPI) demonstrated lower bulk densities due to their porous structures and larger particle sizes, while GA and OSAS produced denser microcapsules. Encapsulation efficiency was the highest for protein‐based microcapsules (79.41–89.12%) and the lowest for GA and OSAS. The surface oil percentage of protein‐based microcapsules (1.41–4.40%) was lower than that of the other microcapsules. Protein‐based microcapsules showed concave and cracked surfaces, while GA and OSAS microcapsules were spherical and smooth. CHI improved reconstitution performance, leading to faster dissolution. During simulated gastrointestinal digestion, protein‐based microcapsules released more free fatty acids (FFAs) in the intestinal phase, while CHI‐modified SPI microcapsules showed a delayed release pattern due to thicker walls.Protein‐based wall materials were more effective for sea buckthorn pulp oil microencapsulation, providing higher encapsulation efficiency, better flow properties and releasing more FFAs. The addition of CHI led to the layer‐by‐layer self‐assembly of the microcapsule wall and resulted in sustained release during in vitro intestinal digestion. These findings suggested the potential of protein‐based microcapsules for targeted delivery and improved applications of bioactive oils in the food industry. © 2024 Society of Chemical Industry. Published by John Wiley & Sons Ltd [ABSTRACT FROM AUTHOR]

Colloidosomes, pioneering microcapsules composed of coagulated colloidal particles assembled at the interface of emulsion droplets, have garnered significant attention due to their remarkable properties and potential applications in targeted and controlled drug delivery. Their unique core-shell architecture offers unparalleled advantages, including tunable permeability, mechanical strength and encapsulation capabilities for a wide range of therapeutic agents. These versatile carriers have demonstrated remarkable potential in delivering small molecules, biomacromolecules, genetic materials and even living cells, addressing challenges associated with conventional drug delivery systems. Colloidosomes can be fabricated through various techniques, encompassing emulsion-based, nature-of-colloids-based and emerging methods such as microfluidics and 3D printing. Comprehensive characterization, employing techniques like electron microscopy, spectroscopy and rheology, is crucial for understanding their structural, physical and functional properties. Remarkable advancements have been achieved in developing stimuli-responsive, targeted and multi-functional colloidosomes, enabling precise spatiotemporal control, selective accumulation and integrated functionalities for theranostic applications. Despite their immense potential, challenges remain in scaling up production, ensuring long-term stability, navigating regulatory landscapes and facilitating clinical translation. Addressing these obstacles through collaborative efforts, advanced characterization and the integration of emerging technologies is paramount for unlocking the full potential of colloidosomes in revolutionizing drug delivery strategies and realizing personalized medicine. [ABSTRACT FROM AUTHOR]

In this study, a combination of Serratia nematophila L2 and Bacillus velezensis W24 was used to biocontrol Sclerotinia sclerotiorum. When the mixed ratio of L2 to W24 was 1:1, the inhibition rate on the growth of S. sclerotiorum was 88.1 %. To gain a large number of bacteria, the culture medium and conditions were optimized. When the medium formula involved molasses (8.890 g/L), soy peptone (6.826 g/L), and NaCl (6.865 g/L), and the culture conditions were 32 °C, inoculum 4%, rotation speed 200 rpm, and pH 7, the maximum amounts of bacterial cells obtained. In order to prepare microcapsules, spray drying conditions were optimized. These conditions included the soluble starch concentration of 30 g/100 mL, the inlet air temperature of 160 °C, and the feed flow rate of 450 mL/h. Under these optimized conditions to prepare microcapsules, the mixed strain (L2 and W24) exhibited a survival rate of 93.9 ± 0.9% and a viable bacterial count of 6.4 × 1012 cfu/g. In addition, microcapsules (GW24Ms) which contained strains L2 and W24 had good storage stability. In the pot experiment, GW24Ms could effectively reduce the disease of soybean plants and the control effect was 88.4%. Thus, the microbial agent represents a promising biocontrol solution for managing Sclerotinia in soybean. • The GW24 (W24 and L2 strains were mixed) could inhibit the growth of Sclerotinia sclerotiorum. • The culture conditions and medium of GW24 were optimized. • The GW24 microcapsules were prepared by spray drying. • The GW24 microcapsules had great storage ability. • The GW24 microcapsules had great effects on S. sclerotiorum. [ABSTRACT FROM AUTHOR]

Microcapsule-based self-healing cementitious composite (MSCC) offers autonomous damage repair, extending the service life of structures. However, most of the existing studies focus on static behavior and healing effectiveness but rarely explore dynamic responses. This study developed the mesoscale modeling approach to investigate MSCC behavior under dynamic split tensile loading. At the mesoscale, MSCC can be treated as a four-phase composite consisting of coarse aggregates, interfacial transition zones, cement mortar, and microcapsules. Alternatively, it can be simplified as a two-phase composite comprising a homogeneous mortar matrix and microcapsules. Four-phase and two-phase mesoscale MSCC models were developed for 2D simulations, while a two-phase 3D model was also developed for comparison. Mesoscale numerical simulations were conducted based on Split-Hopkinson Pressure Bar Brazilian disk-splitting tests, considering various strain rates. Simulation results of different mesoscale models were compared with experimental results. All of the models accurately predicted the tensile strength of MSCC, with the 2D four-phase model providing the best representation of failure modes and crack propagation. Both experimental and numerical data exhibited obvious strain rate effects, indicating that MSCC's mechanical properties were sensitive to the loading rate. Dynamic increase factors were obtained, quantifying rate sensitivity. The obtained dynamic mechanical properties of MSCC provide insights for designing MSCC components and structures that can better withstand collisions or explosions. [ABSTRACT FROM AUTHOR]

Coffee and coffee by-products contain several chemical compounds of great relevance, such as chlorogenic acid (CGA), trigonelline, and caffeine. Furthermore, yeasts have been the target of studies for their use as probiotics because of their interesting biochemical characteristics. The combined administration of probiotic microorganisms with components that provide health benefits mediated by alginate encapsulation is an alternative that ensures the stability of cells and chemical compounds. In this context, the aim of this work was to co-encapsulate the probiotic yeast Kluyveromyces lactis B10 and extracts of green coffee beans, coffee silverskin, and PVA (black, green or immature, and sour coffee beans). The bioactive composition, antioxidant and antimicrobial activities of the extracts, microcapsule morphological characteristics and encapsulation efficiency, ability of the encapsulation to protect the yeast cells subjected to gastrointestinal conditions, and antioxidant activity of the microcapsules were evaluated. All the evaluated extracts showed antioxidant activity, of which PVA showed 75.7% and 77.0%, green coffee bean showed 66.4% and 45.7%, and coffee silverskin showed 67.7% and 37.4% inhibition of DPPH and ABTS•+ radicals, respectively, and antimicrobial activity against the pathogenic bacteria E. coli, Salmonella, and S. aureus, with high activity for the PVA extract. The microcapsules presented diameters of between 1451.46 and 1581.12 μm. The encapsulation efficiencies referring to the yeast retention in the microcapsules were 98.05%, 96.51%, and 96.32% for green coffee bean, coffee silverskin, and PVA, respectively. Scanning electron microscopy (SEM) showed that the microcapsules of the three extracts presented small deformations and irregularities on the surface. The K. lactis cells encapsulated in all treatments with the extracts showed viability higher than 8.59 log CFU/mL, as recommended for probiotic food products. The addition of green coffee bean, coffee silverskin, and PVA extracts did not reduce the encapsulation efficiency of the alginate microcapsules, enabling a safe interaction between the extracts and the K. lactis cells. [ABSTRACT FROM AUTHOR]

The ionic gelation for preserving the antioxidant activity of the protein hydrolysate from encapsulated lionfish (Pterois volitans, L.) muscle was evaluated. A 22 factorial design was used. The factors evaluated were sodium alginate concentration (1.75% and 3.5% w/v) and calcium chloride concentration (3% and 5% w/v). The response variables were encapsulation efficiency and preservation of antioxidant activity. The beads obtained were classified as microcapsules (2–3 mm) and were mostly spherical, with a weight ranging from 12 to 38 mg. Encapsulation efficiency ranged from 37 to 55.47%, while the preservation of antioxidant activity ranged from 43.3 to 64.5%. The best treatment for preserving the in vitro antioxidant activity of the protein hydrolysate was the one with 1.75% w/v sodium alginate and 3% w/v calcium chloride, which showed an encapsulation efficiency of 53.96%, preservation of antioxidant activity of 64.5%, and free radical scavenging (DPPH) of 22.73%. [ABSTRACT FROM AUTHOR]

Nowadays, the use of antioxidant compounds and natural preservatives instead of synthetic preservatives has a unique and fundamental role in the food industry due to their known harms and diseases. One of these compounds with known antioxidant effects is red sugar beet betalains, which have been investigated for microencapsulation. In this study, betalain microcapsules were prepared by the "ionic gelation" method using sodium alginate and guar gum with amounts of 0.25, 0.5, 0.75, 1, 1.5, and 2 mg. Betalain microcapsules were characterized for size, loading efficacy, cumulative release, and morphological characteristics. Also, the characteristics of minimum inhibition concentration (MIC), minimum bactericidal concentration (MBC), and the inhibitory percentage of free radicals (DPPH) for microcapsules were calculated. All data were analyzed using Duncan's one-way variance analysis method. In general, the results show that the percentage of loading efficacy and cumulative release increased up to 1.5 mg betalain, and then up to 2.5 mg experienced a significant decrease. Also, microcapsules had spherical, homogeneous, and uniform forms. In treatments with amounts higher than 1.5 mg, agglomeration between particles coincided with increasing particle size and was based on microcapsules characteristics. Finally, microcapsules including 1.5 mg betalain were selected as the optimum treatment based on the characteristics of the maximum loading efficacy and release, homogenous appearance, lowest MIC and MBC, and the maximum DPPH. [ABSTRACT FROM AUTHOR]

In this study, a composite wall material was prepared by blending whey protein isolate-D-xylose mixture and their Maillard reaction product with sodium alginate, which were then used for encapsulating proanthocyanidin to fabricate proanthocyanidin microcapsules. By characterizing the morphology, investigating stability, and assessing the in vitro antioxidant activity of different proanthocyanidin microcapsules, the advantages of microencapsulation of proanthocyanidin and the superiority of using Maillard reaction product as a wall material were elucidated. The results indicated that the microcapsules formed using the Maillard reaction product achieved an encapsulation efficiency of 98.60%±0.09%, with a proanthocyanidin content of 49.97±0.87 mg/g and a particle size of 1219.61±388.24 μm, exhibiting good granular morphology. Compared to microcapsules without the Maillard reaction, those formed with it demonstrated enhanced stability under conditions of 90 ℃, pH≤4, pH=10, and in gastric digestion fluid. Furthermore, when the proanthocyanidin concentration reached 30 μg/mL, the microcapsules formed with the Maillard reaction product exhibited stronger in vitro antioxidant activity. This study lays the groundwork for further development and utilization of proanthocyanidin microcapsules, offering new insights into the development and advancement of proanthocyanidin microcapsule food products.

To investigate the application of lemongrass essential oil in extending the shelf life of pickle. This study used lemongrass essential oil as the core material, sodium carboxymethyl starch and sodium caseinate as wall materials to prepare lemongrass essential oil microcapsules, and examined the effects of the mass ratio of sodium carboxymethyl starch to sodium caseinate on physicochemical properties, microscopic morphology, thermal stability, and others of lemongrass essential oil microcapsules. Furthermore, the effects of microencapsulation on the chemical composition of the essential oil and the antibacterial activity against major pathogenic bacteria in pickle was evaluated. Results showed that when the mass ratio of sodium carboxymethyl starch to sodium caseinate was 1:5 and 1:9, there was no significant difference in the essential oil encapsulation rate (P>0.05), which was 98.29% and 96.90%, respectively. The appearance was spherical and blocky. With the increasing sodium caseinate content, the micropores on the surface of the microcapsules gradually decreased, and the cavities became smaller. The thermogravimetric curves showed that the temperature corresponding to the maximum weight loss rate of microcapsules was increased with the increasing casein content, reaching a maximum of 314.27 ℃, while that of pure essential oil was only 106.27 ℃. Gas chromatgraphy-mass spectrometry (GC-MS) results showed that essential oil microcapsulation treatment retained multiple antibacterial ingredients of essential oils such as nerol (34.69%), geranyl acetate (27.41%), linalool (5.65%) and caryophyllene (6.50%). This conferred lemongrass essential oil microcapsules strong antibacterial properties against the main spoilage bacteria Bacillus subtilis in pickle and Staphylococcus epidermidis, the bacteria that cause packaging bags to bulge, with the minimum inhibitory concentration of 97.66 µg/mL for Bacillus subtilis and 195.31 µg/mL for Staphylococcus epidermidis, and the maximum bactericidal concentration of 1562.5 µg/mL for both bacteria. In summary, it is feasible to use sodium carboxymethyl starch and sodium caseinate as encapsulating agents to prepare lemongrass essential oil microcapsules, with a desirable inhibitory effect on the main spoilage bacteria in pickle. This research would provide a new perspective for further exploring the application of lemongrass essential oil in extending the shelf life of pickle.

In order to improve the stability and functional properties of casein-derived bioactive peptides (CP) in yogurt, the peptides were microencapsulated using sodium alginate and sucrose fatty acid esters as the wall material, which was determined based on encapsulation efficiency and peptide loading, and the developed microcapsules were applied in yogurt. Scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) proved the successful encapsulation of the peptides. The microcapsules had good sustained release properties, and the release rate was (62.57 ± 1.17)% after 3 h of intestinal digestion. The microencapsulated bioactive peptides improved the water-holding capacity, hardness and viscosity of yogurt, and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability of yogurt with the bioactive peptides was (63.73 ± 1.97)%. The microencapsulated bioactive peptides were not degraded during yogurt fermentation by lactic acid bacteria, and the functional properties of yogurt were enhanced by addition of the bioactive peptides.

In order to compare the antimicrobial and fungicidal properties of common natural plant extracts against dominant molds in purple rice and to investigate their application in purple rice storage, this study isolated and purified molds in moldy purple rice, and identified the dominant molds by microscopic examination and molecular biology. On this basis, the inhibitory properties of six natural plant extracts, citral, cinnamaldehyde, p-anisaldehyde, tea polyphenols, thymol and eugenol, were investigated against dominant molds of purple rice. The natural plant extracts with the best bacteriostatic properties were selected and their minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) against dominant molds were determined. Then the best preparation process of cinnamaldehyde microcapsules was optimized by orthogonal test, and the microcapsules were packed in non-woven bags after drying and applied in the accelerated storage test of purple rice at 35 ℃. Finally, moisture, mold content, odor, and color difference were used as indicators of the freshness of purple rice to evaluate the preservation effect of cinnamaldehyde microcapsules on purple rice. The results showed that the dominant molds of moldy purple rice were Aspergillus versicolor, Aspergillus chevalieri, Cladosporium tenuissimum, Aspergillus candidus and Rhizomucor pusillus, cinnamaldehyde had the best inhibitory effect on the above molds, and its MIC was measured as 2, 1, 1, 2, 1 mg/mL, and MBC was measured as 4, 8, 4, 16, 4 mg/mL, respectively. The optimal preparation process of cinnamaldehyde microcapsules was as follows: The concentration of sodium alginate was 3%, the concentration of calcium chloride was 1%, the wall-core ratio was 12:1, and the distance between the liquid surface of the pelleting was 25 cm, and the encapsulation rate of the cinnamaldehyde microcapsules produced by the process was 96.67%, and the oil-carrying rate was 61.27%. The cinnamaldehyde microcapsules made the freshness indexes of purple rice better than the blank control group, indicating that the prepared cinnamaldehyde microcapsules have a positive effect on the preservation of purple rice.

In this study, the impact of phase-change microcapsules (PCM) on asphalt performance was investigated through a series of orthogonal experiments. These experiments focus on the evaluation of the effect of the urea-formaldehyde (melamine-urea-formaldehyde) resin as a shell material and w-tetradecane as a core material on the synthetic efficiency of PCM. The optimal preparation process for PCM was analyzed. Differential scanning calorimetry and dynamic shear rheology were employed to assess the performance of the PCM-modified asphalt (referring to as phase change bitumen). The findings indicated that the most effective synthetic parameters were determined for PCM at an emulsifier concentration of 7 wt. %, an emulsification speed of 2 000 r/min, a mass ratio of core to wall material of 1:1, a 1: 7 oil-to-water volume ratio, a synthetic time of 90 min, and a reaction temperature of 80 °C. Under such conditions, PCM exhibited a latent heat of 117 J/g. Furthermore, the microcapsule shell presented excellent sealing properties, ensuring the stability of asphalt within the range required for construction temperature. The PCM-modified asphalt showed an exothermic interval from -7. 1 to -17. 9 °C and an endothermic interval from 2. 3 to 13. 5 °C. The PCM-modified asphalt presented a phase-change enthalpy of 5. 1 J/g at a microcapsule concentration of 7 wt. %. More importantly, the incorporation of PCM effectively slowed down the hardening process of the PCM-modified asphalt and maintained its stability at room temperature. The developed phase-change asphalt exhibits great potential for application. [ABSTRACT FROM AUTHOR]

In this study, a novel micromechanics-based damage model is proposed for the damage evolution of a two-component microencapsulated-based self-healing polymer composite. In this way, a representative volume element (RVE) including an epoxy matrix with randomly distributed poly(methyl methacrylate) (PMMA) microcapsules is modeled in DigimatTM software and analyzed in Abaqus®. A new technique is developed to investigate the progressive damage by pre-inserted cohesive elements along all element boundaries of the epoxy matrix, PMMA shell, and capsule-matrix interfaces with the bilinear traction–separation law. Moreover, the impact of interface bonding strength, interface fracture energy, and PMMA microcapsules volume fraction on the load-carrying capacity of the RVEs under uniaxial tension loading was studied. The results indicated that the tensile strength of the self-healing polymer composite increased as the interfacial strength and fracture energy increased from 10 to 60 MPa and 100 to 1000 J/m2, respectively. Furthermore, the higher volume fraction of 5% PMMA microcapsules results in a lower load-carrying capacity of self-healing polymer composite with a strength of 4.9 N. A similar trend of Young's modulus was observed for microcapsule-loaded epoxy composite compared to the pristine epoxy matrix. The micromechanical model has proper accuracy in predicting the tension behavior of self-healing composite in comparison to experimental results. Finally, two healing strategies are considered for the damaged RVE. [ABSTRACT FROM AUTHOR]

Microcapsule-based self-healing concrete (MSC) has been widely studied, with a focus on static behavior and self-healing effectiveness. However, the dynamic mechanical properties of MSC have rarely been studied. This study presents a mesoscale numerical investigation of the dynamic compressive behavior of MSC under impact loading. In mesoscale, MSC is regarded as a four-phase composite material mainly composed of coarse aggregates, interface transition zones, cement mortar, and microcapsules. A pseudo 3D numerical model is constructed by combining a slice of a detailed mesoscale model with a homogenous 3D model. The mesoscale MSC slice models with different mass fractions of microcapsules (0%, 2%, 5%, and 8%) are constructed. Different coarse aggregate shapes (i.e., circles, ellipses, and polygons) are considered. The uniaxial dynamic compressive behaviors of MSC materials under loads of different strain rates are numerically simulated and compared with those from split Hopkinson pressure bar tests previously done by the authors. The comparison results show that the present mesoscale model can accurately predict the compressive strength and failure mode of MSC. The effects of the microcapsules ratio and strain rate on the dynamic strength are studied. Results show that the MSC compressive strength decreases with the increase in microcapsules and increases with the increase in strain rate. The dynamic increase factor (DIF) of the specimen is jointly contributed by the material DIF, inertial constraints, and heterogeneity. Different aggregate shapes have little effect on the simulation results of MSC behavior. The obtained dynamic mechanical properties of MSC may assist in designing MSC to resist collisions or explosions. [ABSTRACT FROM AUTHOR]

Hydrophobized soils have functional hydrophobic coatings to delay or restrict water infiltration and thus prevent infrastructure failure and long-term degradation. Over time, hydrophobized soils will be subjected to degradation under the action of external stresses, leading to the loss of its functional properties. Microencapsulation approaches, initially developed for self-healing applications emerge as a potential solution to enhance, switch (from hydrophilic) or prolong the longevity of hydrophobized soils. The aim of this study is to produce and investigate the effectiveness of microencapsulation to impart hydrophobicity in granular materials in response to external stimuli. In this research, polydimethylsiloxane (PDMS), with hydrophobic properties, is encapsulated in calcium alginate microcapsules with the ionic gelation method. The effectiveness of the microcapsules to induce hydrophobicity is investigated by mixing sand with microcapsules and quantifying the change of the contact angle and water drop penetration time (measures of hydrophobicity) under an external trigger, i.e., under drying and consecutive wetting–drying cycles. The results show that microcapsules release the hydrophobic cargo (PDMS) during shrinkage. After drying, the PDMS content in sand increased to 0.1–0.8% by mass of sand. The released hydrophobic cargo (PDMS) induced hydrophobicity in sands, reflected by a contact angle increase from 29.7° to at least 87.7°. The amount of polydimethylsiloxane encapsulated is a key parameter controlling the release of hydrophobic cargo. In addition, 4% capsule content in sands is identified as an effective microcapsule content in inducing hydrophobicity. [ABSTRACT FROM AUTHOR]

Islet allotransplantation offers a promising cell therapy for type 1 diabetes, but challenges such as limited donor availability and immunosuppression persist. Microencapsulation of islets in polymer-coated alginate microcapsules is a favored strategy for immune protection and maintaining islet viability. This study introduces Poly [2-(methacryloyloxy)ethyl]trimethylammonium chloride (PMETAC) as an innovative coating material for microcapsules. PMETAC enhances biocompatibility and durability, marking a significant advancement in islet encapsulation. Our approach combines alginate with PMETAC to create Langerhans islet microcapsules, simplifying material composition and preparation and ultimately lowering costs and increasing clinical applicability. Our comprehensive evaluation of the stability (including osmotic stability, thermal stability, and culture condition stability) and cytotoxicity of a novel microencapsulation system based on alginate-PMETAC-alginate offers insights into its potential application in islet immunoisolation strategies. Microcapsules with PMETAC content ranging from 0.01 to 1% are explored in the current work. The results indicate that the coatings made with 0.4% PMETAC show the most promising outcomes, remaining stable in the mentioned tests and exhibiting the required permeability. It was shown that the islets encapsulated in this manner retain viability and functional activity. Thus, alginate microcapsules coated with 0.4% PMETAC are suitable for further animal trials. While our findings are promising, further studies, including animal testing, will be necessary to evaluate the clinical applicability of our encapsulation method. [ABSTRACT FROM AUTHOR]

In this paper, microcapsules with acidic pH stimulus responsiveness were prepared through a one-step in situ polymerization method and a layer-by-layer assembly method. The effects of factors such as chitosan (CS) concentration, polymerization time, polymerization process temperature, and the number of polymerization layers on the performance of microcapsules were explored, and microcapsules with optimal performance were prepared and added to the epoxy coating. The morphology and structure of the microcapsules were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and zeta potential testing. The thermal stability and sustained release properties of the microcapsules were studied through thermogravimetric analysis and sustained release curve testing. Through scratch experiments, immersion experiments, salt spray experiments, and electrochemical impedance spectroscopy tests, the impact of the added amount of microcapsules on the self-healing performance and anti-corrosion performance of the coating in complex environments was explored. The results show that the optimal preparation process of acidic pH-responsive microcapsules requires that the concentration of chitosan is 2 mg/mL, the polymerization time of the polyelectrolyte layer is 8 h, the heating temperature during the polymerization process is 75 °C, and the number of polyelectrolyte layers is three. The prepared acidic pH-responsive microcapsules have good morphology, pH sensitivity, and thermal stability. The average particle size is approximately 203 μm, the drug loading rate reaches 59.74%, and the encapsulation rate reaches 63.99%. The optimal added amount of the acidic pH-responsive microcapsule coating is 15 wt%. The coating has a dual-trigger mechanism underlying it stimulus response capability and has an obvious stimulus response to acidic pH. It can inhibit corrosion in non-scratch areas, and its anti-corrosion ability is significantly stronger than that of epoxy coatings and ordinary self-healing coatings. The coating has a stronger repair effect and anti-corrosion ability when the environmental pH becomes acidic. [ABSTRACT FROM AUTHOR]

Dental resin composites are widely used in clinical settings but often face longevity issues due to the development and accumulation of microcracks, which eventually lead to larger cracks and restoration failure. The incorporation of microcapsules into these resins has been explored to introduce self-healing capability, potentially extending the lifespan of the restorations. This study aims to enhance the performance of self-healing dental resins by optimizing the microcapsules–resin matrix physicochemical interactions. Poly(urea–formaldehyde) (PUF) microcapsules were reinforced with melamine and subsequently subjected to surface functionalization with 3-aminopropyltriethoxysilane (APTES) and (3-mercaptopropyl)trimethoxysilane (MPTMS). Additionally, microcapsules were functionalized with a bilayer approach, incorporating tetraethyl orthosilicate (TEOS) with either APTES or MPTMS. X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) confirmed an increased Si:C ratio from 0.006 to 0.165. The functionalization process did not adversely affect the structure of the microcapsules or their healing agent volume. Compared to PUF controls, the functionalized microcapsules demonstrated enhanced healing efficiency, with TEOS/MPTMS-functionalized microcapsules showing the highest performance, showing a toughness recovery of up to 35%. This work introduces a novel approach to functionalization of microcapsules by employing advanced silanizing agents such as APTES and MPTMS, and pioneering bilayer functionalization protocols through their combination with TEOS. [ABSTRACT FROM AUTHOR]

In this paper, self‐healing microcapsules were prepared by in situ polymerization using poly(vinyl alcohol) as the emulsifier, urea‐formaldehyde resin as the shell material, and alkyd resin as the core material. The average diameter of the obtained microcapsules was about 20 μm and the encapsulation rate of alkyd resin was 50.7 wt.%. The self‐healing coating was prepared by adding 5 wt.% of microcapsules to the pure polyurethane coating and then coated on AA2024‐T3 substrate. The self‐healing effect was evaluated by scanning electron microscopy. Electrochemical impedance spectroscopy tests and neutral salt spray tests confirmed that the self‐healing coating had good anticorrosion properties. [ABSTRACT FROM AUTHOR]

The aim of the study was to design microcapsules with a core of blueberry fruit extracts (Vaccinium myrtillus L.) using the ionotropic gelation method and then assess the effect of the type of extracts used and the combination of polymers on the profile of phenolic compounds, their in vitro bioavailability, stability during storage, as well as their antioxidant characteristics and cytotoxic activity against colon cancer cells while assessing biocompatibility against normal colon epithelial cells. Encapsulation efficiency (EE), ranging from 8.79 to 74.55%, significantly depended on the extract used and the type of carrier. It was shown that the addition of pectin (Pect) and whey protein isolate (WPI) to alginate (Alg) improved the efficiency of the encapsulation process. For this version of microcapsules, the highest antioxidant activity, phenolic compound content and their stability during storage were also demonstrated. The estimated content of phenolic compounds ranged from 0.48 to 40.07 mg/g, and the dominant compound was cyanidin 3-O-glucoside. In turn, the highest bioavailability of these compounds and the highest cytotoxic activity against cancer cells were characterized by microcapsules with Alg and WPI. Nevertheless, good biocompatibility with normal colon epithelial cells was demonstrated for all versions of microcapsules. The obtained data indicate that the tested variants of microcapsules protect the bioactive compounds of blueberry fruit extracts, which translates into maintaining their health-promoting properties. [ABSTRACT FROM AUTHOR]

Copyright of Paint & Coatings Industry (0253-4312) is the property of Paint & Coatings Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and Objectives: The extremely high sensitivity of unsaturated fatty acids to oxidation and the problems related to their storage and consumption in liquid form are among the most important obstacles to the use of these resources in feeding farm animals, along with problems such as extensive biohydrogenation and adverse effects on the normal functioning of the rumen ruminants. In addition, the decrease in the amount of feed consumed and the decrease in the acceptability of carcasses and products due to the unpleasant smell are other reasons for the reluctance of livestock breeding units to use fish oil. So the aim of this study was to determination of spray dry microencapsulation effects on fatty acid profile and nutrient content, physical and chemical characteristics and oxidative stability of fish and sunflower oil, compared with ca-salts in vitro. Materials and Methods: In this research, a completely randomized design was used in the statistical analysis of the data related to the chemical composition, physical properties, and oxidation parameters after the production of the fatty acid sample in order to statistically analyze the data related to the oxidation resistance of various types of encapsulated supplements. In time, temperature and different levels of minerals, a factorial design based on a completely random design was used. Microcapsules produced with different oil sources (free fatty acids vs. triacylglycerol of fish and sunflower oil), different wall material systems (Physical blend of carbohydrate and protein sources vs. Maillard reaction products of them) and different ratio of core oil to wall materials. The conditions for preparation of emulsions and stages of drying and storage of produced microcapsules were based on the method provided by researchers with the same coating materials and fish and sunflower oil as oil sources. Fish and sunflower oil were added to the initial mixture with ratios of 1:2, 1:1 and 2:1 (coating materials to oil). In addition to glycerol oils, oil-in-water emulsions were also prepared from fish and sunflower fatty acids. To dry the emulsions, a spray dryer was used with an inlet air temperature of 130°C and an outlet temperature of 60-70°C. Determining the amount of nutrients (fat, dry matter, organic matter, calcium, different parts of the cell wall, different carbohydrate and protein parts and fat extraction, making methyl ester and determining the pattern of fatty acids) in the composition of microcapsules produced using standard procedures were performed. The particle size of the produced emulsions and powders was determined using the laser diffraction technique. Microcapsules and calcium salts of fish oil and sunflower were exposed to temperatures of 25 and 60 degrees for 15, 30 and 45 days, and every two weeks one sample of each supplement was analyzed in order to evaluate the amount of peroxide value. For each supplement, 3 replicates were evaluated at each time and temperature. Results: Emulsions made from triacylglycerol's have higher stability over time compared with FFA sources and were used for spray drying and further analysis. Different oil sources (fish oil vs sunflower oil) have no effects on microencapsulation efficiency, microencapsulation yield. However, wall material system has its effects. Maillard reaction products had higher encapsulation efficiency than physical blends and resulting microcapsules had higher microencapsulation efficiency, lower oxidative state parameters and more preserved fatty acid profile. Encapsulation with Maillard reaction products resulted in more oxidative stability in different storage conditions (different time and temperatures, with or without mineral stimulated oxidation), but the core oil type and ratio to wall materials affect the results. Sunflower oil gives the more oxidative stability than the fish oil, but higher the oil content of microcapsules, higher the oxidation. Oil content also significantly affects fatty acid profile of microcapsules. Results showed that fatty acid Ca- salts had highest oxidative protection between protection strategies. Conclusion: Although microencapsulation protected oils from oxidation, incomplete data about nutrient availability, nutritional value and gastrointestinal tract digestibility of microencapsulated oils compared with a large data set about Ca-salt, warrants further in vivo studies. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of thermochromic microcapsules on the surface coating performance of basswood board, two types of microcapsules prepared with syringaldehyde and sodium tripolyphosphate crosslinking agents were added to a UV primer and coated on the surface of basswood board. The color-change effect of the surface coating on basswood board with microcapsules added with syringaldehyde as the crosslinking agent was better than that with microcapsules added with sodium tripolyphosphate as the crosslinking agent, and the color difference varied more significantly with temperature. The effect of the two types of microcapsules on the glossiness of the surface coating on basswood board was relatively weak. The glossiness of the surface coating on basswood board with microcapsules containing syringaldehyde as the crosslinking agent showed an overall increasing trend with the increase in microcapsules, and the change trend was relatively gentle. The glossiness of the surface coating on basswood board with microcapsules containing sodium tripolyphosphate as the crosslinking agent increased first and then decreased as the amount of microcapsules added increased. The addition of microcapsules with syringaldehyde as the crosslinking agent had no significant effect on the reflectance in the visible light band of the surface coating on basswood board. Among the two groups of samples, the hardness increase in the surface coating on basswood board with syringaldehyde as the crosslinking agent was more significant. The adhesion level of the coating on the surface of the basswood board with the two microcapsules did not change. Neither of the microcapsules had a significant effect on the impact resistance of the surface on basswood board. In the comprehensive analysis, the surface coating on basswood board with microcapsules added with syringaldehyde as the crosslinking agent at a content of 4.0% had better comprehensive performance, better surface morphology, better color-change effect, and moderate mechanical properties. The color difference was found to be 21.0 at 25 °C, the reflectivity was found to be 57.06%, the hardness was found to be 3H, the adhesion was found to be five, and the impact resistance was found to be three. [ABSTRACT FROM AUTHOR]