In the last three decades,carbon dioxide(CO_(2)) emissions have shown a significant increase from various sources.To address this pressing issue,the importance of reducing CO_(2) emissions has grown,leading to increas...In the last three decades,carbon dioxide(CO_(2)) emissions have shown a significant increase from various sources.To address this pressing issue,the importance of reducing CO_(2) emissions has grown,leading to increased attention toward carbon capture,utilization,and storage strategies.Among these strategies,monodisperse microcapsules,produced by using droplet microfluidics,have emerged as promising tools for carbon capture,offering a potential solution to mitigate CO_(2) emissions.However,the limited yield of microcapsules due to the inherent low flow rate in droplet microfluidics remains a challenge.In this comprehensive review,the high-throughput production of carbon capture microcapsules using droplet microfluidics is focused on.Specifically,the detailed insights into microfluidic chip fabrication technologies,the microfluidic generation of emulsion droplets,along with the associated hydrodynamic considerations,and the generation of carbon capture microcapsules through droplet microfluidics are provided.This review highlights the substantial potential of droplet microfluidics as a promising technique for large-scale carbon capture microcapsule production,which could play a significant role in achieving carbon neutralization and emission reduction goals.展开更多
Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material co...Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material combining the solvent evaporation method and spray drying method.The protection by the outer capsule wall was used to prolong the service life of the corrosion inhibitor.The dispersion,encapsulation,thermal stability of microcapsules,and the degradation rate of capsule wall in concrete pore solution were analyzed by ultra-deep field microscopy,scanning electron microscopy,thermal analyzer,and sodium ion release rate analysis.The microcapsules were incorporated into mortar samples containing steel reinforcement,and the effects of double-layered microcapsule corrosion inhibitors on the performance of the cement matrix and the actual corrosion-inhibiting effect were analyzed.The experimental results show that the double-layered microcapsules have a moderate particle size and uniform distribution,and the capsules were completely wrapped.The microcapsules as a whole have good thermal stability below 230 ℃.The monolayer membrane structure microcapsules completely broke within 1 day in the simulated concrete pore solution,and the double-layer membrane structure prolonged the service life of the microcapsules to 80 days in the simulated concrete pore solution before the core material was completely released.The mortar samples containing steel reinforcement incorporated with the double-layered microcapsule corrosion inhibitors still maintained a higher corrosion potential than the monolayer microcapsule corrosion inhibitors control group at 60 days.The incorporation of double-layered microcapsules into the cement matrix has no significant adverse effect on the setting time and early strength.展开更多
In this paper, the preparation technique of lavender essential oil microcapsules and the construction method of aromatic textiles were expounded, and the research status of bed curtains and lavender microcapsules at h...In this paper, the preparation technique of lavender essential oil microcapsules and the construction method of aromatic textiles were expounded, and the research status of bed curtains and lavender microcapsules at home and abroad was analyzed and studied from the perspective of application in textiles. The application of lavender essential oil to bed curtains through the microcapsule technique was put forward to allow lavender essential oil to play its role of helping sleep in bed curtains. This paper expounded the material selection and preparation technique of lavender microcapsule agents, and put forward the preparation method of microcapsules with mixed solutions of pure Chinese medicine extracts and natural essences as core material and high-viscosity epoxy resin as wall materials. The post-processing techniques and the spray ironing method for clothing were studied and developed, and these techniques and methods were applied to bed curtains, and good results were obtained.展开更多
Pesticide-loaded flexible carriers that allow for deformation and adhesion on crop leaves is an effective way to improve pesticide utilization.In interfacial polymerization,the addition of octaphenyl polyoxyethylene(O...Pesticide-loaded flexible carriers that allow for deformation and adhesion on crop leaves is an effective way to improve pesticide utilization.In interfacial polymerization,the addition of octaphenyl polyoxyethylene(OP)with different hydrophile lipophilic balances(HLBs)into the oil phase can regulate the flexibility of pyraclostrobinloaded microcapsules(MCs).Due to differences in amphiphilicity and molecular structure,OP redistributed on the oil-water two-phases and oil-water interface.With increasing HLB,the proportion of OP entering the aqueous phase increased.Furthermore,more OP with low HLB remained in the oil phase and occupied the oil-water interface,and these OPs participated in and regulated the interfacial polymerization to increase the thickness,reduce the compactness of the shell,and increase the hydroxyl and ether bond contents in the shell.Therefore,pyraclostrobin-loaded MCs with low HLB(11.5-12.5)OP-7 exhibited flexible deformation,strong foliar adhesion,good scouring resistance,and a high control effect on peanut leaf spot,which the disease severity was 3.67.For high HLB(16),OP-21-prepared MCs with compact shells were safer to zebrafish,which the safety index was 23.81.Using the amphiphilicity of OP molecules to drive their redistribution in an encapsulation system to regulate interfacial polymerization is an effective way to control the structure and performance of pesticideloaded MCs.展开更多
Aim A RP- HPLC method for determination of lycopene in microcapsules was established. Methods The HPLC assay was performed on an Alltima Cls (4.6 mm × 250 mm, 5μm) column with a mixture of methanol-THF-water ...Aim A RP- HPLC method for determination of lycopene in microcapsules was established. Methods The HPLC assay was performed on an Alltima Cls (4.6 mm × 250 mm, 5μm) column with a mixture of methanol-THF-water (66:30:4, V/V/V) as mobile phase at a flow rate of 1.5 mL·min^-1 and the UV detection wavelength was 472 nm. Results The linear range of lycopene was 3.6-18 μg·mL^-1, r = 0.999 8, the average recovery was from 99.81% to 101.06% with RSD less than 1.83%. The RSD of intra-day and interday precision were less than 3.34%. Conclusion The method is simple, accurate and suitable for the determination of lycopene in microcapsules.展开更多
Object To investigate the therapeutic effect of microencapsulated porcine retinal pigmented epithelial cells (RPE-M) transplantation on rat model of Parkinson's disease (PD). Methods Primary porcine RPE cells wer...Object To investigate the therapeutic effect of microencapsulated porcine retinal pigmented epithelial cells (RPE-M) transplantation on rat model of Parkinson's disease (PD). Methods Primary porcine RPE cells were harvested by enzyme digestion and expanded in culture medium. Determine the levels ofdopamine (DA) and homovanillic acid (HVA) by high performance liquid chromatography electrochemical (HPLC) assay, and the levels of brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) were detected by ELISA. Alginate-polylysine-alginate (APA) microencapsulated cells were produced by using a high voltage electrostatic system. PD rat model was established by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB). After that, the RPE-M was transplanted into the corpus striatum of PD rat, and then the rotation test scores were recorded and biochemical changes of the corpus striatum were tested. Results The levels of DA, HVA, BDNF and GDNF secreted by RPE were stable in the RPE culture supernatant and were not changed by the microencapsulation. Eighty-three percent rats developed PD by unilateral lesion of 6-OHDA in the MFB. The RPE-M transplantation had therapeutic effect on 33% PD rats. Conclusion Porcine RPE cells grow actively in vitro and could secrete DA, HVA, BDNF, and GDNF constantly, which does not be affected by the passage culture and the APA miroencapsulation. RPE-M transplantation of may be a curative therapy for PD.展开更多
Aim PLA/PLGA was used as biodegradable and biocompatible carriers to achieve sustained release of estradiol (E 2). Methods Microcapsules (MC) were prepared by an emulsification solvent extraction method, and then ...Aim PLA/PLGA was used as biodegradable and biocompatible carriers to achieve sustained release of estradiol (E 2). Methods Microcapsules (MC) were prepared by an emulsification solvent extraction method, and then the properties and in vitro drug release behavior of MC were examined. An analysis of variance (ANOVA) was used to test the statistical significance. Then, multiple comparisons were made with a T method between levels to examine the significance of difference further. For all the results a P value 】0 05 was considered statistically insignificant . Results Under the same conditions, the water adding speed and the particle size had significant effects ( P 【0 01) on the entrapment efficiency of MC; the water adding speed and the concentration of PLA in the oil phase had significant effects ( P 【0 01) on the diameter MC in medium. Release of E 2 from MC was influenced significantly ( P 【0 01) by the water adding speed and the type and molecule weight of the polymers. But the differences between levels of the variates were not all significant. Conclusion E 2 PLA/PLGA MC with various properties can be formed when the formulation and the technology were changed accordingly.展开更多
Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcell...Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose (EC) by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows: ( 1 ) the ratio of EC (20cps) to EC (45cps) was 50:50; (2) the ratio of plasticizer to coating materials was 20% ;and (3) the ratio of resin-mefformin complexes to coating materials was 5 : 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.展开更多
The nanostructured copper/microcapsule containing liquid core materials composite(copper/liquid microcapsules composite) was prepared using direct current(DC) electrodeposition method.The surface morphology and mi...The nanostructured copper/microcapsule containing liquid core materials composite(copper/liquid microcapsules composite) was prepared using direct current(DC) electrodeposition method.The surface morphology and microstructure of composite were investigated by means of scanning electron microscopy(SEM),transmission electron microscopy(TEM) and X-ray diffraction(XRD).The results show that the microstructure of electrodeposited layer transformed from bulk crystal to nano structure because of the participation of microcapsules.The diameters of microcapsules and the copper grain sizes in the composite were 2?20 μm and 10?20 nm,respectively.In addition,the electrodeposition mechanism of composite in the deposition process followed electrochemistry theory,which was proved by the theoretical analysis result and the experiment results.Meanwhile,the co-deposition process model was presented.展开更多
The fish oil consists of a variety of unsaturated fat,generally extracts from fish scraps by the steps of steaming,crushing and separation. Fish oil is rich in triglycerides,glycerol ether phosphate,lipids,fat-soluble...The fish oil consists of a variety of unsaturated fat,generally extracts from fish scraps by the steps of steaming,crushing and separation. Fish oil is rich in triglycerides,glycerol ether phosphate,lipids,fat-soluble vitamins,and protein degradation products,etc. Microencapsulation technology can significantly improve the antioxidant stability of fish oil by wrapping a tiny amount of material in a polymer film. Supercritical carbon dioxide (SC-C) and spray-drying are being evaluated most favorably in fish oil processing. Factors influencing the microencapsulate efficiency are discussed including emulsifier density,collagen proportion,solid proportion,inlet air temperature and the ratio of core material to wall material. And the effect of microencapsulation can be measured by the effect of embedding,and SEM (scanning electron microscope) can be used in evaluating the ultrastructure of encapsulated fish oil.展开更多
UV-curable polyurethane prepolymer and photoinitiator 1173 were facilely encapsulated in a poly(urea-formaldehyde) shell, which was in situ formed by the polymerization of formalde-hyde and urea in an oil-in-water e...UV-curable polyurethane prepolymer and photoinitiator 1173 were facilely encapsulated in a poly(urea-formaldehyde) shell, which was in situ formed by the polymerization of formalde-hyde and urea in an oil-in-water emulsion. The diameters of the microcapsules ranged from 118 μm to 663 μm depending on agitation speed, and were obtained via optical mi-croscopy and scanning electron microscopy analyses. The encapsulation percent and the yield of microcapsules prepared at the agitation speed of 600 r/min can reach 97.52wt% and 65.23wt%, respectively. When the water-borne polyurethane (WPU) coating embedded with the prepared microcapsules were scratched, the healing agent could be released from rup-tured microcapsules and lled the scribed region. The excellent anticorrosion properties of the WPU coating embedded with the prepared microcapsules were con rmed by the results obtained from both electrochemical impedance spectroscopy and Tafel curves.展开更多
Luseweilei is an easily-bursted microcapsule insecticide. A test of effectiveness of the insecticide to control the larvae of Dendrolimus superans T. was carried out in larch forest in Baoan Forest Farm of Nehe City, ...Luseweilei is an easily-bursted microcapsule insecticide. A test of effectiveness of the insecticide to control the larvae of Dendrolimus superans T. was carried out in larch forest in Baoan Forest Farm of Nehe City, Heilongjiang Province, in April 2001. The solutions of different concentrations (1:150, 1:250, 1:350, and 1:450 Luseweilei : water) were sprayed on the larch trunk before the overwintering larvae climbing on trees and the spraying lengths (height) designed were 1.0, 2.5, and 3.5 m high from ground. The control result showed that spraying 150-, 250-, and 350-fold solutions of the insecticide all produced a good control result, with a mortality rate of 97%, but the 450-fold solution only produced 70% mortality. It is concluded that this insecticide can be used as a kind of good insecticide to control the overwintering larvae of D. superans in spring. Spraying 350-fold solution of easy-burst microcapsule insecticide and one meter spraying length are recommended for the future application..展开更多
Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation rea...Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation reaction. The products were characterized by means of Fourier transform infrared spectrometry, ^13C NMR spectrometry and ^31p NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.展开更多
The flowability of five kinds of microencapsulation powders,with differentβ-carotene contents and by two alternative particle-forming technologies i.e.spray-drying and starch-catching beadlet technology,was meas- ure...The flowability of five kinds of microencapsulation powders,with differentβ-carotene contents and by two alternative particle-forming technologies i.e.spray-drying and starch-catching beadlet technology,was meas- ured.The actual flow properties of the five powders were compared based on bin-flow test,and three flow indexes (Hausner ratio,repose angle and flow index)were measured.It was found that the repose angle is the most suitable index to reflect the flowability of these powders for the particle properties would not be altered due to compaction or tapping during the measuring process.Particle size and particle size distribution play most important roles in the flowability of these granular materials,which was also influenced by other factors like shape,surface texture,sur- face roughness,etc.Microcapsules with wall material of gelatin and a layer of modified starch absorbed on the sur- face showed excellent flowabilities and good mechanical properties,and they are favorable for tabletting to supply β-carotene.展开更多
Bone defects caused by trauma,tumor,or osteoarthritis remain challenging due to the lack of effective treatments in clinic.Stem cell transplantation has emerged as an alternative approach for bone repair and attracted...Bone defects caused by trauma,tumor,or osteoarthritis remain challenging due to the lack of effective treatments in clinic.Stem cell transplantation has emerged as an alternative approach for bone repair and attracted widespread attention owing to its excellent biological activities and therapy effect.The attempts to develop this therapeutic approach focus on the generation of effective cell delivery vehicles,since the shortcomings of direct injection of stem cells into target tissues.Here,we developed a novel core-shell microcapsule with a stem cell-laden core and a biomass shell by using all-aqueous phase microfluidic electrospray technology.The designed core-shell microcapsules showed a high cell viability during the culture procedure.In addition,the animal experiments exhibited that stem cell-laden core-shell microcapsules have good biocompatibility and therapeutic effect for bone defects.This study indicated that the core-shell biomass microcapsules generated by microfluidic electrospray have promising potential in tissue engineering and regenerative medicine.展开更多
Microcapsulated chlorocyclophosphazenes were synthesized,and then microcapsulated chlorocyclo- phosphazene/polypropylene(PP)composites were prepared.The results showed that microcapsulated chlorocyclo- phosphazene had...Microcapsulated chlorocyclophosphazenes were synthesized,and then microcapsulated chlorocyclo- phosphazene/polypropylene(PP)composites were prepared.The results showed that microcapsulated chlorocyclo- phosphazene had good high thermal stability through thermogravimetric analysis(TGA).The flammability and mechanical properties of microcapsulated chlorocyclophosphazene/polypropylene composites were investigated by limiting oxygen index experiment,UL 94V flame retardancy test,cone calorimetry,tensile experiment,and impact test,respectively.It was shown that the microcapsulated chlorocyclophosphazene/PP composites had better tensile strength,impact strength,flame retardant properties and smoke suppress properties compared with chlorocyclo- phosphazene/PP composites.展开更多
Microcapsule technology is a kind of technology wrapping the solid or liquid into minute-sized particles within the field of micrometer or millimeter with film forming materials. This thesis introduces microcapsule te...Microcapsule technology is a kind of technology wrapping the solid or liquid into minute-sized particles within the field of micrometer or millimeter with film forming materials. This thesis introduces microcapsule technology of phase change materials and its main functions and the structural composition, preparation methods and characterization technology of microcapsule of phase change materials. The microcapsule of phase change materials is small in size and its temperature remains unchanged during the process of heat absorption and heat release. It is of great value in research and application prospect due to these characteristics.展开更多
To study the influences of phase change material(PCM)microcapsules in clothing on human thermal responses,a mathematical model is developed.The improved Stolwijk’s model is used to simulate human thermo-regulatory pr...To study the influences of phase change material(PCM)microcapsules in clothing on human thermal responses,a mathematical model is developed.The improved Stolwijk’s model is used to simulate human thermo-regulatory process,and the coupled heat and moisture transfer including the moisture sorption/desorption of fibers and effects of phase transition temperature range on the phase change processes of the PCM is considered in clothing model.Meanwhile,the theoretical predictions are validated by experimental data.Then,the interactions between human body thermal responses and the heat and moisture transfer in clothing are discussed by comparing the prediction results with PCMs and without PCMs.Also the effects of fiber hygroscopicity on clothing and human thermal responses are compared.The conclusion shows that the clothing with PCMs microcapsules can delay the human temperature variations and decrease the sweat accumulation rate on the skin surface and heat loss during changing of ambient conditions,and fiber hygroscopicity reduces the effect of PCM microcapsules on delaying garment temperature variations very significantly.展开更多
Ultrathin polydopamine microcapsules with hierarchical structure and porosity were prepared for the immobilization of multienzymes using metal-organic framework(MOF) as the template.The multienzyme/MOF composite was f...Ultrathin polydopamine microcapsules with hierarchical structure and porosity were prepared for the immobilization of multienzymes using metal-organic framework(MOF) as the template.The multienzyme/MOF composite was first prepared using a "one-pot" co-precipitation approach via the coordination and self-assembly of zinc ions and 2-methylimidazole in the presence of enzymes.The obtained nanoparticles were then coated with polydopamine thin layer through the self-polymerization of dopamine under alkaline condition.The polydopamine microcapsules with an ultrathin shell thickness of ~48 nm were finally generated by removing the MOF template at acidic condition.Three enzymes were encapsulated in PDA microcapsules including carbonic anhydrase(CA),formate dehydrogenase(FateDH),and glutamate dehydrogenase(GDH).FateDH that catalyzed the main reaction of CO_(2) reduction to formic acid retained 94.7% activity of equivalent free FateDH.Compared with free multienzymes,the immobilized ones embedded in PDA microcapsules exhibited 4.5-times higher of formate production and high catalytic efficiency with a co-factor-based formate yield of 342%.展开更多
Polyurea microcapsules about 2.5 μm in diameter containing phase change material for thermal energy storage application were synthesized and characterized by interfacial polycondensation method with toluene-2,4-diiso...Polyurea microcapsules about 2.5 μm in diameter containing phase change material for thermal energy storage application were synthesized and characterized by interfacial polycondensation method with toluene-2,4-diisocyanate and ethylenediamine as monomers in an emulsion system. Hexadecane was used as a phase change material and OP, which is nonionic surfactant, and used as an emulsifier. The chemical structure and thermal behavior of the microcapsules were investigated by FTIR and thermal analysis respectively. The results show encapsulated hexadecane has a good potential as a solar energy storage material.展开更多
基金supported by the National Natural Science Foundation of China (No.52036006)。
文摘In the last three decades,carbon dioxide(CO_(2)) emissions have shown a significant increase from various sources.To address this pressing issue,the importance of reducing CO_(2) emissions has grown,leading to increased attention toward carbon capture,utilization,and storage strategies.Among these strategies,monodisperse microcapsules,produced by using droplet microfluidics,have emerged as promising tools for carbon capture,offering a potential solution to mitigate CO_(2) emissions.However,the limited yield of microcapsules due to the inherent low flow rate in droplet microfluidics remains a challenge.In this comprehensive review,the high-throughput production of carbon capture microcapsules using droplet microfluidics is focused on.Specifically,the detailed insights into microfluidic chip fabrication technologies,the microfluidic generation of emulsion droplets,along with the associated hydrodynamic considerations,and the generation of carbon capture microcapsules through droplet microfluidics are provided.This review highlights the substantial potential of droplet microfluidics as a promising technique for large-scale carbon capture microcapsule production,which could play a significant role in achieving carbon neutralization and emission reduction goals.
基金Fund by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (No.2018YFD1101002-03)。
文摘Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material combining the solvent evaporation method and spray drying method.The protection by the outer capsule wall was used to prolong the service life of the corrosion inhibitor.The dispersion,encapsulation,thermal stability of microcapsules,and the degradation rate of capsule wall in concrete pore solution were analyzed by ultra-deep field microscopy,scanning electron microscopy,thermal analyzer,and sodium ion release rate analysis.The microcapsules were incorporated into mortar samples containing steel reinforcement,and the effects of double-layered microcapsule corrosion inhibitors on the performance of the cement matrix and the actual corrosion-inhibiting effect were analyzed.The experimental results show that the double-layered microcapsules have a moderate particle size and uniform distribution,and the capsules were completely wrapped.The microcapsules as a whole have good thermal stability below 230 ℃.The monolayer membrane structure microcapsules completely broke within 1 day in the simulated concrete pore solution,and the double-layer membrane structure prolonged the service life of the microcapsules to 80 days in the simulated concrete pore solution before the core material was completely released.The mortar samples containing steel reinforcement incorporated with the double-layered microcapsule corrosion inhibitors still maintained a higher corrosion potential than the monolayer microcapsule corrosion inhibitors control group at 60 days.The incorporation of double-layered microcapsules into the cement matrix has no significant adverse effect on the setting time and early strength.
基金Supported by Undergraduate Training Program for Innovation and Entrepreneurship of Guangxi University of Chinese Medicine in 2023(S202310600084)。
文摘In this paper, the preparation technique of lavender essential oil microcapsules and the construction method of aromatic textiles were expounded, and the research status of bed curtains and lavender microcapsules at home and abroad was analyzed and studied from the perspective of application in textiles. The application of lavender essential oil to bed curtains through the microcapsule technique was put forward to allow lavender essential oil to play its role of helping sleep in bed curtains. This paper expounded the material selection and preparation technique of lavender microcapsule agents, and put forward the preparation method of microcapsules with mixed solutions of pure Chinese medicine extracts and natural essences as core material and high-viscosity epoxy resin as wall materials. The post-processing techniques and the spray ironing method for clothing were studied and developed, and these techniques and methods were applied to bed curtains, and good results were obtained.
基金supported by the National Natural Science of China(32272596)Key Research Development Program of Shandong Province(2022CXGC020710)+2 种基金Shandong Province Agricultural Major Technology Collaborative Promotion Plan(SDNYXTTG-2023-20)Central Publicinterest Scientific Institution Basal Research Fund(No.1610232023005)Major technology projects[110202201029(LS-13)].
文摘Pesticide-loaded flexible carriers that allow for deformation and adhesion on crop leaves is an effective way to improve pesticide utilization.In interfacial polymerization,the addition of octaphenyl polyoxyethylene(OP)with different hydrophile lipophilic balances(HLBs)into the oil phase can regulate the flexibility of pyraclostrobinloaded microcapsules(MCs).Due to differences in amphiphilicity and molecular structure,OP redistributed on the oil-water two-phases and oil-water interface.With increasing HLB,the proportion of OP entering the aqueous phase increased.Furthermore,more OP with low HLB remained in the oil phase and occupied the oil-water interface,and these OPs participated in and regulated the interfacial polymerization to increase the thickness,reduce the compactness of the shell,and increase the hydroxyl and ether bond contents in the shell.Therefore,pyraclostrobin-loaded MCs with low HLB(11.5-12.5)OP-7 exhibited flexible deformation,strong foliar adhesion,good scouring resistance,and a high control effect on peanut leaf spot,which the disease severity was 3.67.For high HLB(16),OP-21-prepared MCs with compact shells were safer to zebrafish,which the safety index was 23.81.Using the amphiphilicity of OP molecules to drive their redistribution in an encapsulation system to regulate interfacial polymerization is an effective way to control the structure and performance of pesticideloaded MCs.
基金Special Research Foundation of Ph.D. Study in University(20040291004)Major Project of Chinese(National Programs for Fundamental Research(2003CB716000)
文摘Aim A RP- HPLC method for determination of lycopene in microcapsules was established. Methods The HPLC assay was performed on an Alltima Cls (4.6 mm × 250 mm, 5μm) column with a mixture of methanol-THF-water (66:30:4, V/V/V) as mobile phase at a flow rate of 1.5 mL·min^-1 and the UV detection wavelength was 472 nm. Results The linear range of lycopene was 3.6-18 μg·mL^-1, r = 0.999 8, the average recovery was from 99.81% to 101.06% with RSD less than 1.83%. The RSD of intra-day and interday precision were less than 3.34%. Conclusion The method is simple, accurate and suitable for the determination of lycopene in microcapsules.
文摘Object To investigate the therapeutic effect of microencapsulated porcine retinal pigmented epithelial cells (RPE-M) transplantation on rat model of Parkinson's disease (PD). Methods Primary porcine RPE cells were harvested by enzyme digestion and expanded in culture medium. Determine the levels ofdopamine (DA) and homovanillic acid (HVA) by high performance liquid chromatography electrochemical (HPLC) assay, and the levels of brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) were detected by ELISA. Alginate-polylysine-alginate (APA) microencapsulated cells were produced by using a high voltage electrostatic system. PD rat model was established by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB). After that, the RPE-M was transplanted into the corpus striatum of PD rat, and then the rotation test scores were recorded and biochemical changes of the corpus striatum were tested. Results The levels of DA, HVA, BDNF and GDNF secreted by RPE were stable in the RPE culture supernatant and were not changed by the microencapsulation. Eighty-three percent rats developed PD by unilateral lesion of 6-OHDA in the MFB. The RPE-M transplantation had therapeutic effect on 33% PD rats. Conclusion Porcine RPE cells grow actively in vitro and could secrete DA, HVA, BDNF, and GDNF constantly, which does not be affected by the passage culture and the APA miroencapsulation. RPE-M transplantation of may be a curative therapy for PD.
文摘Aim PLA/PLGA was used as biodegradable and biocompatible carriers to achieve sustained release of estradiol (E 2). Methods Microcapsules (MC) were prepared by an emulsification solvent extraction method, and then the properties and in vitro drug release behavior of MC were examined. An analysis of variance (ANOVA) was used to test the statistical significance. Then, multiple comparisons were made with a T method between levels to examine the significance of difference further. For all the results a P value 】0 05 was considered statistically insignificant . Results Under the same conditions, the water adding speed and the particle size had significant effects ( P 【0 01) on the entrapment efficiency of MC; the water adding speed and the concentration of PLA in the oil phase had significant effects ( P 【0 01) on the diameter MC in medium. Release of E 2 from MC was influenced significantly ( P 【0 01) by the water adding speed and the type and molecule weight of the polymers. But the differences between levels of the variates were not all significant. Conclusion E 2 PLA/PLGA MC with various properties can be formed when the formulation and the technology were changed accordingly.
文摘Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose (EC) by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows: ( 1 ) the ratio of EC (20cps) to EC (45cps) was 50:50; (2) the ratio of plasticizer to coating materials was 20% ;and (3) the ratio of resin-mefformin complexes to coating materials was 5 : 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.
基金Project(50771010) supported by the National Natural Science Foundation of China
文摘The nanostructured copper/microcapsule containing liquid core materials composite(copper/liquid microcapsules composite) was prepared using direct current(DC) electrodeposition method.The surface morphology and microstructure of composite were investigated by means of scanning electron microscopy(SEM),transmission electron microscopy(TEM) and X-ray diffraction(XRD).The results show that the microstructure of electrodeposited layer transformed from bulk crystal to nano structure because of the participation of microcapsules.The diameters of microcapsules and the copper grain sizes in the composite were 2?20 μm and 10?20 nm,respectively.In addition,the electrodeposition mechanism of composite in the deposition process followed electrochemistry theory,which was proved by the theoretical analysis result and the experiment results.Meanwhile,the co-deposition process model was presented.
文摘The fish oil consists of a variety of unsaturated fat,generally extracts from fish scraps by the steps of steaming,crushing and separation. Fish oil is rich in triglycerides,glycerol ether phosphate,lipids,fat-soluble vitamins,and protein degradation products,etc. Microencapsulation technology can significantly improve the antioxidant stability of fish oil by wrapping a tiny amount of material in a polymer film. Supercritical carbon dioxide (SC-C) and spray-drying are being evaluated most favorably in fish oil processing. Factors influencing the microencapsulate efficiency are discussed including emulsifier density,collagen proportion,solid proportion,inlet air temperature and the ratio of core material to wall material. And the effect of microencapsulation can be measured by the effect of embedding,and SEM (scanning electron microscope) can be used in evaluating the ultrastructure of encapsulated fish oil.
文摘UV-curable polyurethane prepolymer and photoinitiator 1173 were facilely encapsulated in a poly(urea-formaldehyde) shell, which was in situ formed by the polymerization of formalde-hyde and urea in an oil-in-water emulsion. The diameters of the microcapsules ranged from 118 μm to 663 μm depending on agitation speed, and were obtained via optical mi-croscopy and scanning electron microscopy analyses. The encapsulation percent and the yield of microcapsules prepared at the agitation speed of 600 r/min can reach 97.52wt% and 65.23wt%, respectively. When the water-borne polyurethane (WPU) coating embedded with the prepared microcapsules were scratched, the healing agent could be released from rup-tured microcapsules and lled the scribed region. The excellent anticorrosion properties of the WPU coating embedded with the prepared microcapsules were con rmed by the results obtained from both electrochemical impedance spectroscopy and Tafel curves.
文摘Luseweilei is an easily-bursted microcapsule insecticide. A test of effectiveness of the insecticide to control the larvae of Dendrolimus superans T. was carried out in larch forest in Baoan Forest Farm of Nehe City, Heilongjiang Province, in April 2001. The solutions of different concentrations (1:150, 1:250, 1:350, and 1:450 Luseweilei : water) were sprayed on the larch trunk before the overwintering larvae climbing on trees and the spraying lengths (height) designed were 1.0, 2.5, and 3.5 m high from ground. The control result showed that spraying 150-, 250-, and 350-fold solutions of the insecticide all produced a good control result, with a mortality rate of 97%, but the 450-fold solution only produced 70% mortality. It is concluded that this insecticide can be used as a kind of good insecticide to control the overwintering larvae of D. superans in spring. Spraying 350-fold solution of easy-burst microcapsule insecticide and one meter spraying length are recommended for the future application..
文摘Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation reaction. The products were characterized by means of Fourier transform infrared spectrometry, ^13C NMR spectrometry and ^31p NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.
基金Supported by the National-Natural Science Foundation of China (No.20576118) and National High Technology Research and Development Program of China (863 Program, No.2006AA02Z210).
文摘The flowability of five kinds of microencapsulation powders,with differentβ-carotene contents and by two alternative particle-forming technologies i.e.spray-drying and starch-catching beadlet technology,was meas- ured.The actual flow properties of the five powders were compared based on bin-flow test,and three flow indexes (Hausner ratio,repose angle and flow index)were measured.It was found that the repose angle is the most suitable index to reflect the flowability of these powders for the particle properties would not be altered due to compaction or tapping during the measuring process.Particle size and particle size distribution play most important roles in the flowability of these granular materials,which was also influenced by other factors like shape,surface texture,sur- face roughness,etc.Microcapsules with wall material of gelatin and a layer of modified starch absorbed on the sur- face showed excellent flowabilities and good mechanical properties,and they are favorable for tabletting to supply β-carotene.
基金supported by the National Key Research and Development Program of China(2020YFA0908200)the National Natural Science Foundation of China(52073060 and 61927805)the Shenzhen Fundamental Research Program(JCYJ20190813152616459).
文摘Bone defects caused by trauma,tumor,or osteoarthritis remain challenging due to the lack of effective treatments in clinic.Stem cell transplantation has emerged as an alternative approach for bone repair and attracted widespread attention owing to its excellent biological activities and therapy effect.The attempts to develop this therapeutic approach focus on the generation of effective cell delivery vehicles,since the shortcomings of direct injection of stem cells into target tissues.Here,we developed a novel core-shell microcapsule with a stem cell-laden core and a biomass shell by using all-aqueous phase microfluidic electrospray technology.The designed core-shell microcapsules showed a high cell viability during the culture procedure.In addition,the animal experiments exhibited that stem cell-laden core-shell microcapsules have good biocompatibility and therapeutic effect for bone defects.This study indicated that the core-shell biomass microcapsules generated by microfluidic electrospray have promising potential in tissue engineering and regenerative medicine.
基金Supported by the National Natural Science Foundation of China (No.50303005), the Natural Science Foundation of Shanxi Province (No.20041029) and the Project of Science and Technology of Shanxi Province (No.012078).
文摘Microcapsulated chlorocyclophosphazenes were synthesized,and then microcapsulated chlorocyclo- phosphazene/polypropylene(PP)composites were prepared.The results showed that microcapsulated chlorocyclo- phosphazene had good high thermal stability through thermogravimetric analysis(TGA).The flammability and mechanical properties of microcapsulated chlorocyclophosphazene/polypropylene composites were investigated by limiting oxygen index experiment,UL 94V flame retardancy test,cone calorimetry,tensile experiment,and impact test,respectively.It was shown that the microcapsulated chlorocyclophosphazene/PP composites had better tensile strength,impact strength,flame retardant properties and smoke suppress properties compared with chlorocyclo- phosphazene/PP composites.
文摘Microcapsule technology is a kind of technology wrapping the solid or liquid into minute-sized particles within the field of micrometer or millimeter with film forming materials. This thesis introduces microcapsule technology of phase change materials and its main functions and the structural composition, preparation methods and characterization technology of microcapsule of phase change materials. The microcapsule of phase change materials is small in size and its temperature remains unchanged during the process of heat absorption and heat release. It is of great value in research and application prospect due to these characteristics.
基金supported by the National Natural Science Foundation of China (No. 50706017)the Research Funds of Nanjing University of Aeronautics and Astronautics (No.NS2010009)
文摘To study the influences of phase change material(PCM)microcapsules in clothing on human thermal responses,a mathematical model is developed.The improved Stolwijk’s model is used to simulate human thermo-regulatory process,and the coupled heat and moisture transfer including the moisture sorption/desorption of fibers and effects of phase transition temperature range on the phase change processes of the PCM is considered in clothing model.Meanwhile,the theoretical predictions are validated by experimental data.Then,the interactions between human body thermal responses and the heat and moisture transfer in clothing are discussed by comparing the prediction results with PCMs and without PCMs.Also the effects of fiber hygroscopicity on clothing and human thermal responses are compared.The conclusion shows that the clothing with PCMs microcapsules can delay the human temperature variations and decrease the sweat accumulation rate on the skin surface and heat loss during changing of ambient conditions,and fiber hygroscopicity reduces the effect of PCM microcapsules on delaying garment temperature variations very significantly.
基金supported by the National Natural Science Foundation of China (31961133004, 21861132017)the National Key Research and Development Program of China (2018YFA0902200)the Fundamental Research Funds for the Central Universities (PT1917, buctrc201)。
文摘Ultrathin polydopamine microcapsules with hierarchical structure and porosity were prepared for the immobilization of multienzymes using metal-organic framework(MOF) as the template.The multienzyme/MOF composite was first prepared using a "one-pot" co-precipitation approach via the coordination and self-assembly of zinc ions and 2-methylimidazole in the presence of enzymes.The obtained nanoparticles were then coated with polydopamine thin layer through the self-polymerization of dopamine under alkaline condition.The polydopamine microcapsules with an ultrathin shell thickness of ~48 nm were finally generated by removing the MOF template at acidic condition.Three enzymes were encapsulated in PDA microcapsules including carbonic anhydrase(CA),formate dehydrogenase(FateDH),and glutamate dehydrogenase(GDH).FateDH that catalyzed the main reaction of CO_(2) reduction to formic acid retained 94.7% activity of equivalent free FateDH.Compared with free multienzymes,the immobilized ones embedded in PDA microcapsules exhibited 4.5-times higher of formate production and high catalytic efficiency with a co-factor-based formate yield of 342%.
文摘Polyurea microcapsules about 2.5 μm in diameter containing phase change material for thermal energy storage application were synthesized and characterized by interfacial polycondensation method with toluene-2,4-diisocyanate and ethylenediamine as monomers in an emulsion system. Hexadecane was used as a phase change material and OP, which is nonionic surfactant, and used as an emulsifier. The chemical structure and thermal behavior of the microcapsules were investigated by FTIR and thermal analysis respectively. The results show encapsulated hexadecane has a good potential as a solar energy storage material.