Structure Of Microcapsules Research Articles

Ultra-sensitive, fast response microcapsule structure capacitive sensor with encapsulated columnar nano-ZnO for electronic skin

Ultra-sensitive, fast response microcapsule structure capacitive sensor with encapsulated columnar nano-ZnO for electronic skin

Research on enhancing thermal conductivity of phase change microcapsules with nano-copper

Abstract The unique ability of phase change materials (PCMs) to store and release heat makes their integration into building materials promising for reducing energy consumption and enhancing sustainability. In this work, a novel high-thermal-conductivity microencapsulated phase change material was studied, with nano-copper embedded in the microcapsule structure. This modification enhanced thermal conductivity while largely preserving the material’s latent heat storage capacity. Poly(ethyl acrylate) (PEA) is chosen as the capsule shell, whereas a eutectic mixture of decanoic acid (CA) and lauric acid (LA) serves as the core material. The analysis results indicate that as the shell-core mass ratio decreases, the microcapsule size increases, and both thermal conductivity and thermal diffusivity gradually decrease. Moreover, the latent heat capacity of microencapsulated phase change material (MEPCM) increases. When the shell-core mass ratio is 1:1.5, the melting latent heat and solidification latent heat are 81.85 J g−1 and 88.68 J g−1, respectively. nano-copper doping enhances the material’s thermal conductivity and thermal diffusivity by 47.5% and 50%, respectively, leading to a 20.3% improvement in heat storage efficiency. After 200 cycles of testing, the material maintains good thermal reliability and chemical stability. Mortar-based composite materials containing microcapsules were prepared. The mortar composite materials containing microcapsules exhibited minimal influence from heating and cooling, with those containing nano-copper microcapsules demonstrating superior thermal response speeds. The method of doping and modifying MEPCM with nano-copper is a promising approach for effectively reducing the impact of temperature fluctuations on the internal comfort of buildings, improving energy utilization efficiency, and providing reliable solutions for temperature-sensitive applications.

Cathode Performance of ZnMn₂O₄ for Zn Anode Rechargeable Batteries

Zinc anode rechargeable batteries (ZABs) are expecting a promising rechargeable battery for next-generation power systems due to a low cost, environmental compatibility, high safety, and high energy density of Zn anode. Although various cathode materials are currently being investigated, no cathode material with high discharge capacity, cycle stability, and high potential has been reported1 . At present, MnO2 is the most promising materials however, cycle stability is still not enough high. In this study, ZnMn2O4 which is the inactive phase of Zn-MnO2 battery using alkaline electrolyte, was focused as cathode using various acidic electrolyte. Optimization of dopant and also additives to electrolyte was studied.ZnMn2O4 was synthesized with spray pyrolysis method using nitrate solution of Zn and Mn. The cathode was prepared by mixing ZnMn2O4, acetylene black, and PTFE at 7:2:1 weight ratio and pressed onto Ti mesh. The cell consists of Zn anode, glass separator, and the ZnMn2O4 cathode prepared. Charge-discharge measurements were performed in constant current mode with three electrodes cell at current density of 0.2 mA/cm².The prepared ZnMn2O4 powder was a sphere shape and SEM observation suggest that inner of particles are vacant, microcapsule structure. Among the electrolytes examined, 3M Zn(OTf)₂+0.1M Mn(OTf)₂ and 3M ZnSO₄+0.1M MnSO₄ were found to be suitable from cycle stability and discharge capacity. In particular, Zn-ZnMn2O4 cell using 3 M Zn(OTf)₂+0.1M Mn(OTf)2 shows discharge capacity larger than 200mAh/g and more than 50 cycles of charge and discharge.Ex situ XRD showed that the MnO peak was appeared after discharge from 1.9 to 0.8V and it is disappeared to be ZnMn2O4 peaks after charge to 1.9V. Consequently, the charge and discharge of Zn-ZnMn2O4 cell is stored electricity by the redox reaction between Mn2+ and Mn3+. Considering the stable discharge capacity and high potential, Zn-ZnMn2O4 battery is highly interesting as rechargeable large capacity battery. Acknowledgement; This presentation is based on results obtained from a project, JPNP21006, commissioned by the New Energy and Industrial Technology Development Organization (NEDO), Japan.1) N. Zhang, X. Chen, M. Yu, Z. Niu, F. Cheng, J. Chen, Chem Soc Rev, 2020, 49, 4203. Figure 1

Self-healing and wave-absorbing functional coupling of nano-Fe3O4 hybridized microcapsules

As a common high-performance wave absorber, the application prospect of nano-Fe3O4 in cementitious materials is limited due to its defects such as easy agglomeration and possible hydration reaction with cement clinker. In this study, self-healing and wave-absorbing functional coupling materials were synthesized by nano-Fe3O4 hybridized microcapsules. The physical and chemical properties of nano-Fe3O4 hybridized microcapsules were characterized by ESEM (Environmental scanning electron microscopy), XRD (X-ray diffractometer) and FTIR (Fourier transform infrared spectrum), etc. The self-healing properties of microcapsules were assessed. The electromagnetic parameters of microcapsules were measured, and the wave-absorbing performance of microcapsules with different matching thicknesses was assessed. The function coupling mechanism of self-healing and wave-absorbing of microcapsules hybridized by nano-Fe3O4 was revealed. The findings revealed that the residual weights of FM0 and FM40 were 1.28 % and 16.44 %, respectively. The hybrid microcapsules demonstrated the amorphous structure of self-healing microcapsules and the crystal structure characteristics of nano-Fe3O4. The highest strength healing rate of cement mortar mixed with microcapsules was 34.2 %. The minimum reflection loss and the corresponding effective bandwidth of the nano-Fe3O4 hybridized microcapsules with a thickness of 3 mm were −20.32 dB and 7.07 GHz, respectively. The nano-Fe3O4 hybridized microcapsules with core–shell structure exhibit excellent wave-absorbing performance through the functional coupling of dielectric loss and magnetic loss.

Preparation and characterization of Pummelo essential oil microcapsules and their application to preservation of <i>Agricus bisporus</i> (white mushrooms)

Pummelo essential oil is a natural plant oil with antioxidant and antibacterial properties; however, it is poorly stabilized and volatile, which limits its application in food preservation research. In the present work, pummelo essential oil microcapsules were prepared using the complex coalescence method, with pummelo essential oil as the core material and glutenin as the wall material. Pummelo essential oil was successfully encapsulated by glutenin, forming a stable microcapsule structure with enhanced thermal stability. Microcapsules (GH-4) with the addition of 4 mL of pummelo essential oil exhibited the best embedding effect, achieving an encapsulation efficiency of 91%. Compared with GH-0, white mushrooms preserved with GH-4 effectively maintained the hardness of the fruiting body (about 7.5 N), delayed browning (the L* value was about 80), inhibited respiration (about 18×103 mL kg-1 h-1), and slowed the quality deterioration of the white mushrooms. In conclusion, GH-4 microcapsules can be used not only for the preservation of fruits and vegetables but also provide a theoretical basis for sustainable food preservation.

Pesticide delivery microcapsule based on maleic anhydride‐functionalized cellulose nanocrystals‐stabilized pickering emulsion

AbstractThe efficient use of pesticides is conducive to the harmonious coexistence of humans and nature, and pesticide transport carriers can enhance the utilization value of pesticides. However, design flaws in many pesticide carriers have resulted in numerous environmental and toxicity problems. Therefore, this paper proposed a method for synthesizing pesticide microcapsules using Pickering emulsion templates stabilized by maleic anhydride‐functionalized cellulose nanocrystals‐g‐poly (methyl methacrylate) (MACNCs‐g‐MMA), viz., simple radical polymerization of maleic anhydride‐functionalized cellulose nanocrystals with methyl methacrylate in Pickering emulsion. The structure and morphology of microcapsules were characterized via the FT‐IR, XRD, TG‐DTG, and SEM techniques. The imidacloprid‐loaded MACNCs‐g‐MMA (IMI@MACNCs‐g‐MMA) presented a high encapsulation efficiency (~94.13%) and drug loading efficiency (~24.00%). The release behavior was affected by temperature, viz., higher temperature promoted the release of IMI. Regarding the spread and retention on the leaf surface, the IMI@MACNCs‐g‐MMA demonstrated significant advantages over commercial IMI water‐dispersible granules (CG) (36.9° vs. 104.9° for contact angle, 14.3 vs. 30.0 mg cm−2 for retention). This study provides a promising pesticide formula for sustainable agriculture.

Trident-inspired fucoidan-based armor-piercing microcapsule for programmed acute pulmonary embolism treatment

Pulmonary embolism remains the third leading cause of human mortality after malignant tumors and myocardial infarction. Commonly available thrombolytic therapeutic agents suffer from the limitations of very short half-life, inadequate targeting, limited clot penetration, and a propensity for severe bleeding. Inspired by the trident, we developed the armor-piercing microcapsule (MC), fucoidan-urokinase-S-nitrosoglutathione-polydopamine@MC (FUGP@MC), which exhibited a triple combination of photothermal, mechanical and pharmacological thrombolysis for the therapeutic treatment of acute pulmonary embolism (APE). Briefly, the outermost fucoidan layer was utilized for targeting to the APE area. Programmed APE treatment was triggered by near-infrared (NIR) light irradiation. Photothermal thrombolytic therapy was carried out by photothermal conversion of polydopamine. The photothermal conversion broke the S-nitroso bond in S-nitrosoglutathione (GSNO) and produced large amounts of nitric oxide (NO) for mechanical thrombolysis, which subsequently disrupted the interfacial structure of microcapsule to stimulate the release of the urokinase (UK), leading to a triple synergistic thrombolytic effect. The results demonstrated that the embolization residual rate of FUGP@MC (contained ≈ 1452.5 IU/kg UK) group was significantly lower than that of UK (10,000 IU/kg) group (6.35 % VS 16.78 %). Remarkably, FUGP@MC demonstrated a reliable in vivo biosafety proficiency. In summary, trident-inspired armor-piercing microcapsule FUGP@MC reveals a potential avenue for advancing pulmonary embolism therapeutics and promises to be a safer alternative candidate to current drug approaches.

Hyaluronic acid/chitosan microcapsules capped with hollow CuS nanoparticles for NIR/pH dual-responsive drug release

Hollow natural polysaccharide microcapsules have broad applications in drug delivery field due to their excellent biocompatibility and drug loading efficiency. In this paper, pH/near-infrared (NIR) dual-responsive microcapsules composed of hyaluronic acid (HA), chitosan (CS) and hollow CuS (HA/CS/HA@CuS) had been fabricated via a layer-by-layer (LbL) approach. The negative charge, rough surface and hollow structure of microcapsules are very favorable for loading positively charged DOX. As a result, hollow microcapsules display a high drug loading efficiency of 91.15 %. The variation in the degree of amino ionization at different pH values leads to the changes in the electrostatic force between CS/HA multilayers, resulting in the structural change in microcapsules. Therefore, microcapsules exhibit significant pH-responsive drug release properties. In addition, hollow CuS nanoparticles with excellent photothermal conversion ability are capped on the multilayer surface, enabling microcapsules to exhibit excellent NIR-responsive drug delivery properties. Overall, hyaluronic acid/chitosan-based hollow microcapsules with notable pH/NIR dual-responsiveness have been prepared, which can be used as a potential drug carrier for controlled drug delivery and photothermal chemical combination therapy.

Sustained-release effect of eggshell powder microcapsules on lavender essential oil

Eggshells are rich in Ca2+ and organic compounds, which can be taken as coupling agents for sustained-release materials. Essential oils are widely applied due to their excellent volatility, but poor sustained-release stability has limited their development. The study aimed to develop a novel eggshell powder (EP) sustained-release microcapsule, providing a new approach to protect the active ingredients of Lavender essential oil (LEO), and investigated the reasons for EP to regulate protein-polysaccharide microcapsule structure. Experimental results showed when the addition ratio of EP and Whey protein (WPI) was 1: 3, the dosage of LEO was 25%, the microcapsule displayed smooth and porous spherical structure. XRD and FT-IR indicated that a dense and orderly network structure was formed via the cross-linking reaction between eggshell powder and wall materials, which induced protein and polysaccharide to form special spherical hollow sustained-release shell structure through the calcium bridge (-COO-Ca-COO-), then achieved the sustained-release effect on LEO.

Novel eco-friendly nanodiamonds@chitosan hybrid microcapsules via facile electrospraying for self-healing and anticorrosion coating

Nanodiamonds were immobilized into chitosan biopolymer to fabricate hybrid microcapsules via electrospraying technique. Previously optimized electrospraying parameters for the formulation of chitosan microcapsules were adjusted to accommodate the immobilized nanodiamonds and maintain a suitable capsule size for the novel hybrid. The yield and entrapment efficiency of the composite microcapsules, including capsule strength were analyzed. The chemical structure, elemental composition, crystalline phases, size distribution, surface morphology, and thermal stability of microcapsules were assessed by Fourier transform infrared (FTIR) spectroscopy, energy dispersive x-ray spectroscopy (EDX), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), respectively. The results demonstrated a 39 % reduction in the size of composite microcapsules and sphericity improvement after the adjustment. There was a general observation of good yield and immobilization efficiency with the maximum at 96.2 % and 93.8 % for yield and entrapment efficiency, respectively. Characterized composite microcapsules showed desirable morphology, good thermal stability and enhanced mechanical strength, and overall successful fabrication of the hybrid microcapsules. The hybrid microcapsules were subsequently loaded in epoxy resin and coated on a steel substrate to assess their self-healing and anticorrosion abilities. Cross-scratched coating samples were monitored visually for healing efficiency and further analyzed with EIS and potentiodynamic polarization. The self-healing coating showed efficient self-healing and anticorrosion capabilities with a healing efficiency of 97.3 % and a protection efficiency of 99.4 %, confirming the unique feature of the hybrid chitosan-nanodiamonds microparticles for self-healing and anticorrosion purposes.

Inhibited the walnut oil oxidation through the microcapsules that consisted of (−)-Epigallocatechin gallate and sodium caseinate

(−)-Epigallocatechin gallate (EGCG) possesses potent antioxidant properties and can enhance the encapsulation efficiency and stability of oil microcapsule with sodium caseinate (NaCas). Hence, the present study aimed to investigate the effects of different concentrations of EGCG on the physicochemical properties of walnut oil microcapsules. The impact of EGCG on the morphology, structure, physical attributes, and functional traits of walnut oil microcapsules was characterized through scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, molecular docking, thermogravimetric analysis, etc. Results demonstrated that EGCG interacted with NaCas via hydrogen bonding and hydrophobic interactions to form walnut oil microcapsules, significantly enhancing the encapsulation efficiency up to 86.42%. With increasing concentration of EGCG, the NaCas-EGCG complex displayed heightened DPPH free radical scavenging capacity (up to 68.27 μg Trolox/mL). Furthermore, in vitro digestion indicated that the microcapsules could effectively regulate the release rate of free fatty acids. In conclusion, the present study successfully prepared walnut oil microcapsules with elevated oxidative stability by employing EGCG and NaCas as the wall materials, providing new insight for preparing walnut oil microcapsules with improved stability and release properties.

Biomimetic artificial islet model with vascularized microcapsule structures for durable glycemic control

Islet transplantation is a promising strategy for diabetes mellitus treatment as it can recapitulate endogenous insulin secretion and provide long-term glycemic control. Islet models constructed in biomaterial scaffolds that reproduce biological characteristics of native islets is a feasible option to circumvent the dilemma of donor shortage and the requirement of chronic immunosuppression. Herein, we developed bioinspired artificial microcapsule-based islet models with microvessels for glycemic control using microfluidic electrospray strategy. Microfluidic electrospray can generate uniform hydrogel microcapsules with core-shell structure for encapsulating islet cells. The cell-laden microcapsules enabled the efficient transportation of nutrient, oxygen, and insulin; as well as the incorporation with microvessels for prompting glucose responsiveness and molecular exchange. We demonstrated by in vivo experiments that the blood glucose, food intake, and body weight of diabetic mouse models were alleviated, and the glucose tolerance was promoted after the engraftment of islet microcapsules. We further demonstrated the improved functionality of transplanted islet model in insulin secretion, immune escape, and microcirculation using standard histological and molecular analysis. These results indicated that the microcapsules with microvessels are promising artificial islet models and are valuable for treating diabetes.

The Construction of Sodium Alginate/Carboxymethyl Chitosan Microcapsules as the Physical Barrier to Reduce Corn Starch Digestion.

To enhance the resistant starch (RS) content of corn starch, in this work, carboxymethyl chitosan/corn starch/sodium alginate microcapsules (CMCS/CS/SA) with varying concentrations of SA in a citric acid (CA) solution were designed. As the SA concentration increased from 0.5% to 2%, the swelling of the CMCS/CS/SA microcapsule decreased from 15.28 ± 0.21 g/g to 3.76 ± 0.66 g/g at 95 °C. Comparatively, the onset, peak, and conclusion temperatures (To, Tp, and Tc) of CMCS/CS/SA microcapsules were higher than those of unencapsulated CS, indicating that the dense network structure of microcapsules reduced the contact area between starch granules and water, thereby improving thermal stability. With increasing SA concentration, the intact and dense network of CMCS/CS/SA microcapsules remained less damaged after 120 min of digestion, suggesting that the microcapsules with a high SA concentration provided better protection to starch, thereby reducing amylase digestibility. Moreover, as the SA concentration increased from 0.5% to 2%, the RS content of the microcapsules during in vitro digestion rose from 42.37 ± 0.07% to 57.65 ± 0.45%, attributed to the blocking effect of the microcapsule shell on amylase activity. This study offers innovative insights and strategies to develop functional starch with glycemic control properties, holding significant scientific and practical value in preventing diseases associated with abnormal glucose metabolism.

Effect and application of spray drying and freeze drying on characterization of walnut oil microcapsules

In the current study, a walnut oil (WO) emulsion was prepared with WO as the core material and sodium caseinate and maltodextrin as the wall materials. The effects of spray drying (SD) and freeze drying (FD) on the structure and quality of WO microcapsules were compared, and the role of WO microcapsules as a substitute for commercial creamer in coffee was investigated. The results demonstrated that the WO microcapsules prepared by the SD method had dense microstructure, spherical particles, no oil drop aggregation, small particle size, good fluidity, an embedding rate of up to 93.60%, an unsaturated fatty acid content of 87.00%, and no significant difference in thermal stability or stability of the restored emulsion compared with FD. The freeze-dried WO microcapsules have irregular structure, porous surface structure, high oil content on the surface, 76.84% embedding rate, some accumulation of droplets, large grain size, and poor fluidity. The electronic nose and electronic tongue results reveal that the microcapsules prepared by the two methods have similar flavor when applied to coffee. The spray-dried WO microcapsules are prepared with a flavor closer to that of commercial creams. In summary, microcapsules prepared by SD are superior to FD and are promising for industrial production; further, the nondairy creamer based on WO has great potential for coffee application.

Synthesis of inorganic/organic hybrid-shell antibacterial polyurea microcapsules loaded with Ag/TiO2 nanoparticles

Silver/titanium dioxide (Ag/TiO2) nanoparticles, renowned as effective inorganic antibacterial agents with a wide spectrum of activity and minimal resistance induction, encounter challenges when incorporated into organic substrates. This integration often leads to particle aggregation, resulting in a substantial reduction in antibacterial efficacy. This study devised a novel approach involving loading Ag/TiO2 nanoparticles onto polyurea microcapsules (PUMC), forming hybrid-shelled microcapsules (Ag/TiO2-PUMC) using silane coupling agents. The preparation of polyurea microcapsules offers the advantages of rapid synthesis and mild reaction conditions, facilitating industrial-scale production. Additionally, loading Ag/TiO2 nanoparticles onto polyurea microcapsules helps alleviate the aggregation issue, and the organic nature of polyurea microcapsules enhances compatibility with organic substrates. Characterization techniques, including SEM, TEM, FTIR, XRD, UV–visible absorption spectroscopy, EPR and thermogravimetric analysis, were employed to confirm the successful grafting of Ag/TiO2 nanoparticles onto the PUMC. A comparative analysis between the two silane coupling agents, KH550 and KH792, revealed that the dual amino-functional silane coupling agent, KH792, played a pivotal role in chain extension during the microcapsule self-polymerization process. The antibacterial activity of the Ag/TiO2-PUMC was evaluated against Escherichia coli and Staphylococcus aureus. Remarkably, the hybrid-shelled microcapsules exhibited outstanding antibacterial efficacy, achieving a 99.99% antibacterial rate within just 0.5 hours. This performance surpassed unmodified Ag/TiO2 nanoparticles, highlighting the enhanced antibacterial efficacy of the hybrid-shelled microcapsule structure. This study presents a successful synthesis strategy for inorganic/organic hybrid-shelled antibacterial microcapsules and provides valuable insights for refining inorganic antibacterial agents. The demonstrated approach holds substantial promise for advancing the field of organic antibacterial materials.

Preparation and chemical properties of microencapsulation developed with mulberry anthocyanins and silk fibroin

Anthocyanins, as natural pigments with bright color and non-toxic side effect, are widely used in the agricultural products processing field. In the present research, mulberry anthocyanin microcapsules were prepared with silk fibroin and gum arabic as wall materials for the possible application in cosmetics industry. Anthocyanin microcapsule encapsulation efficiency was up to 95.71% in the condition of silk fibroin: gum arabic at 2:1, wall-core ratio of 7.5:1 and solid content at 15%. Microcapsules improved the thermal stability and pH stability of mulberry anthocyanins with higher retention rates. Besides, scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and fourier transform infrared (FTIR) were applied to analyze the surface morphology, structure, crystallinity and thermal properties of mulberry anthocyanin microcapsules. The results indicated that anthocyanins were embedded in the capsules with crystalline structures, good encapsulation and enhanced thermal stability.

NIR Light-Fuse Drug-Free Photothermal Armor-Piercing Microcapsule for Femoral Vein Thrombosis Therapy.

Acute thrombosis and its complications are leading global causes of disability and death. Existing thrombolytic drugs, such as alteplase and urokinase (UK), carry a significant bleeding risk during clinical treatments. Thus, the development of a novel thrombolysis strategy is of utmost urgency. Based on the previous work, the hollow structure of microcapsules (MC) is fabricated. Subsequently, armor-piercing MC, known as Fucoidan/S-Nitrosoglutathione/Melanin@MC (FGM@MC) is obtained, using a layer-by-layer (LBL) self-assembly method. Utilizing near-infrared (NIR) light as a trigger, the FGM@MC demonstrated photothermal thrombolysis at the site of thrombus due to its stable and outstanding photothermal properties. Simultaneously, photothermal stimulation leads to the release of a significant amount of nitric oxide from the FGM@MC, resulting in cavitation effects for mechanical thrombolysis. In vivo experiments confirmed the stable release of nitric oxide under NIR light irradiation. Treatment of femoral vein thrombosis in rats revealed that the thrombolytic effectiveness of FGM@MC+NIR (53.71%) is comparable to that of UK (59.70%). Notably, FGM@MC does not interfere with the coagulation function of rats and exhibits a favorable safety profile. In conclusion, this study demonstrates that the drug-free armor-piercing microcapsule has significant potential in the treatment of thrombosis, offering a safe and effective alternative to traditional thrombolytic therapies.

Ethyl Cellulose-Core, OSA Starch-Shell Electrosprayed Microcapsules Enhance the Oxidative Stability of Loaded Fish Oil.

The encapsulation and the oxidative stability of cod liver fish oil (CLO) within coaxial electrosprayed (ethyl cellulose/CLO) core-(octenyl succinic anhydride, OSA-modified starch) shell, and monoaxial electrosprayed ethyl cellulose/CLO microcapsules were investigated. Core-shell (H-ECLO) and monoaxial (ECLO) electrosprayed microcapsules with an average diameter of 2.8 ± 1.8 µm, and 2.2 ± 1.4 µm, respectively, were produced. Confocal microscopy confirmed not only the core-shell structure of the H-ECLO microcapsules, but also the location of the CLO in the core. However, for the ECLO microcapsules, the CLO was distributed on the microcapsules' surface, as also confirmed by Raman spectroscopy. Atomic force microscopy showed that the average surface adhesion of the H-ECLO microcapsules was significantly lower (5.41 ± 0.31 nN) than ECLO microcapsules (18.18 ± 1.07 nN), while the H-ECLO microcapsules showed a remarkably higher Young's modulus (33.84 ± 4.36 MPa) than the ECLO microcapsules (6.64 ± 0.84 MPa). Differential scanning calorimetry results confirmed that the H-ECLO microcapsules enhanced the oxidative stability of encapsulated CLO by about 15 times, in comparison to non-encapsulated oil, mainly by preventing the presence of the fish oil at the surface of the microcapsules, while ECLO microcapsules enhanced the oxidative stability of CLO about 2.9 times due to the hydrophobic interactions of the oil and ethyl cellulose. Furthermore, the finite element method was also used to evaluate the electric field strength distribution, which was substantially higher in the vicinity of the collector and lower in the proximity of the nozzle when the coaxial electrospray process was employed in comparison to the monoaxial process.

MICROENCAPSULATION BISOPROLOL FUMARATE WITH EUDRAGIT E PO BY SOLVENT EVAPORATION METHOD

Objective: This study aimed to develop and optimize the microcapsule formula of bisoprolol fumarate-Eudragit EPO by double-emulsion solvent evaporation.
 Methods: The preparation of bisoprolol fumarate-Eudragit EPO microcapsule was done in three different ratios 1: 3 (F1), 1: 4 (F2), and 1: 5 (F3), followed by characterization of each of the microcapsule formula using Fourier transform infrared, scanning electron microscopy, particle size analyzer. Further analysis included investigation of the drug loading, entrapment efficiency, solubility in pH 6.8, and the difference among dissolution profiles of each microcapsule using one-way ANOVA.
 Results: Infra-red spectrum showed no chemical interaction between bisoprolol fumarate and Eudragit E PO in microcapsules. The morphology and structure of F1 microcapsule was irregular spheres, while F2 and F3 were regular spheres. The average particle distribution of microcapsules was 24.765±0,236 μm (F1), 28.245±0,252 μm (F2), and 40.634±0,218 μm (F3). The drug loading was 7.691±0,087 % (F1), 8.922±0,056 % (F2), and 9.012±0,133% (F3). The encapsulation efficiency was 4.980 % (F1), 5.857%(F2), and 6,285 %(F3). The average amount of bisoprolol fumarate released in pH 6.8 was 2.113±0,289 % (F1), 1.954±0,015 % (F2), and 1.619±0,020 % (F3). The dissolution profile between each formula was statistically different (p value= 0,000).
 Conclusion: As the low value of drug loading and encapsulation efficiency in each formula, we concluded that the microencapsulation formula with Eudragit EPO by solvent evaporation method is not effective to entrap bisoprolol fumarate.

Encapsulation and characterization of soy protein-based ω-3 medium- and long- chain triacylglycerols microencapsulated with diverse homogenization techniques for improving oxidation stability

Recently, MLCTs have attracted considerable attention as a potential alternative to traditional oils due to their suppressive effect on fat accumulation and insulin sensitivity. In this study, the microcapsules of MLCTs with superior performance were fabricated through different homogenization processes to overcome the limitations of ω-3 medium- and long- chain triacylglycerols (MLCTs), including poor stability and prone oxidation. Additionally, the impact of various homogenization techniques, namely, high-pressure, ultrasound, and cavitation jet, on the particle structure, encapsulation efficiency, and oxidation stability of microcapsules (MLCTs) was investigated. The MLCTs microcapsules fabricated through high-pressure homogenization had a smaller particle size of 295.12 nm, lower PDI of 0.24, and a higher zeta-potential absolute value of 32.65, which significantly improved their dispersion and encapsulation efficiency, reaching 94.56 % after the spray-drying process. Furthermore, the low moisture content and superior storage stability of MLCTs microcapsules have the potential to serve as carriers of liposoluble actives.