Solid lipid nanoparticles loaded with bovine serum albumin（BSA） were prepared by a double emulsion method. As the mass fraction of the model drug BSA increased from 0 to 15%, the particle size gradually increased. T...Solid lipid nanoparticles loaded with bovine serum albumin（BSA） were prepared by a double emulsion method. As the mass fraction of the model drug BSA increased from 0 to 15%, the particle size gradually increased. The physical stability of the nanoparticles was investigated by zeta potential measurement and they were shown to be quite stable. Fluorescence spectroscopy confirmed that the loaded position of BSA was on the interface between the inner aqueous phase and the solid lipid phase. Both Fourier-transform infrared spectroscopy and circular dichroism spectra indicate that BSA in the nanoparticles was not destroyed, but the secondary structure was disrupted slightly.展开更多
With the benefit fierce competition in the steel industry market in recent years,double cold reduction products have been developed towards strength improvement and thickness reduction.The traditional cold-rolling lub...With the benefit fierce competition in the steel industry market in recent years,double cold reduction products have been developed towards strength improvement and thickness reduction.The traditional cold-rolling lubrication process with a fixed flow rate and concentration cannot solve the problems,which are uncontrollable plate shape and the excessive consumption of lubricating oil.Moreover,based on the analysis of the traditional direct aplication lubrication system of double cold reduction mill,a set of design scheme suitable for the emulsion pipeline direct mixing lubrication system of double cold reduction mill unit was proposed.The design completed the selection of key components,which included the static mixer and atomization nozzle selection,pump and oil pump design selection,pipeline design selection,flow type selection,pressure gauge selection,electronic control cabinet design selection and other eight aspects.Equipment of the emulsion pipeline direct mixing lubrication system of double cold reduction has been developed.Comparing with characteristics of the traditional direct aplication lubrication system,the emulsion pipeline direct mixing lubrication system was better applied to the production practice of a 1220 double cold reduction mill.The consumption of ton of steel was reduced by 9.6%.The rolling energy consumption and fuel consumption comprehensive costs decreased by 10.7%,and the strip steel section thickness difference was reduced by 19.3%.In addition,the plate shape quality defect rate decreased by 25.6%,otherwise creating a large economic benefit for the unit and promoting the application value.展开更多
Insulin entrapped nanocapsules to use polylactide （PLA） as the encapsulating material were prepared through a modified water-in-oil-in-water （W/O/W） emulsification and solvent evaporation method, The average parti...Insulin entrapped nanocapsules to use polylactide （PLA） as the encapsulating material were prepared through a modified water-in-oil-in-water （W/O/W） emulsification and solvent evaporation method, The average particle size of PLA nanocapsules obtained was decreased to （181.5 ± 8.4） nm, and capably adjusted from 180 to 370 nm by using different types and content of nonionic emulsifiers. The influence of emulsifiers on property of nanocapsules was discussed in detail. The effects of spans and tweens to modify the size of the nanocapsules were different, which can be due to the distribution of the surfactants on the inner interface between the inner water and oil of the double emulsion. The encapsulation efficiency and drug release of nanocapsules were affected obviously by the content and type of emulsifiers.展开更多
In this work, monodisperse giant polymersomes are fabricated by dewetting of water-in-oil-in-water double emulsion droplets which are assembled by amphiphilic block copolymer molecules in a microfluidic device. The de...In this work, monodisperse giant polymersomes are fabricated by dewetting of water-in-oil-in-water double emulsion droplets which are assembled by amphiphilic block copolymer molecules in a microfluidic device. The dewetting process can be tuned by solvation between solvent and amphiphilic block copolymer to get polymersomes with controllable morphology. Good solvent （chloroform and toluene） hinders dewetting process of double emulsion droplets and gets acornlike polymersomes or patched polymersomes. On the other hand, poor solvent （hexane） accelerates the dewetting process and achieves complete separation of inner water phase from oil phase to form complete bilayer polymersomes. In addition, twin polymersomes with bilayer membrane structure are formed by this facile method. The formation mechanism for different polymersomes is discussed in detail.展开更多
A scalable and versatile strategy was developed for the fabrication of uniform polymeric microspheres with controllable interconnected porous structures. Uniform water-in-oil-in-water emulsions with linear poly(methyl...A scalable and versatile strategy was developed for the fabrication of uniform polymeric microspheres with controllable interconnected porous structures. Uniform water-in-oil-in-water emulsions with linear poly(methyl methacrylate-glycidyl methacrylate) in the oil phase were generated by two-step premix membrane emulsification and used for constructing the microspheres. During the emulsion solidification process, internal water droplets were packed densely together, forming a thin oil film between the internal and external water phases. After solvent diffusion, the thin film can be ruptured and pores can be templated from the internal water droplets to form interconnected porous structures. Membranes with various pore sizes were obtained. The osmotic pressure and Laplace pressure balance were used to control the porosity and pore size precisely. The proposed method enables the fabrication of functional polymeric microspheres with uniform and controllable porous structures and particle sizes. This improves their performance and broadens the scope of their applications, especially in chromatographic separation.展开更多
An easy method is presented to fabricate monodisperse magnetic macroporous polymer beads（MMPBs）. Waterin-oil high internal phase emulsion（HIPE） is prepared by emulsifying aqueous iron ions solution in an oil phase...An easy method is presented to fabricate monodisperse magnetic macroporous polymer beads（MMPBs）. Waterin-oil high internal phase emulsion（HIPE） is prepared by emulsifying aqueous iron ions solution in an oil phase containing monomers. The HIPE is introduced into a simple microfluidic device to fabricate monodisperse（water-in-oil）-in-water double emulsion droplets. The droplets serve as microreactors to synthesize Fe3O4 nanoparticles and are on-line polymerized to form MMPBs. The prepared MMPBs display uniform size, interconnected porous structure, superparamagnetic behavior and uniform distribution of Fe3O4 in polymer matrix. The MMPBs are characterized by scanning electron microscopy（SEM）, Fourier transform infrared spectroscopy（FTIR）, X-ray diffraction（XRD）, transmission electron microscopy（TEM）, vibrating sample magnetometry（VSM）. We believe that this method is a universal technique in preparing macroporous nanocomposite beads.展开更多
This article presents sequential inkjet-based method to produce double emulsions as templates to fabricate morphology-controlled and inner-modified hole-shell microparticles. This sequential printing strategy for prod...This article presents sequential inkjet-based method to produce double emulsions as templates to fabricate morphology-controlled and inner-modified hole-shell microparticles. This sequential printing strategy for producing double emulsions circumvents complex wettability modification of the microchannels in lithography-based microfluidic device and largely saves the reagent in comparison to the coaxial two-phase jet in glass capillary. The formation of hole-shell structures is attributed to the diffusion of solvent out of droplets into butanol at the interface between oil and extract phase. The change of hole size is controlled by different diffusion rate, which is determined by changing the volume ratio of butanol and alcohol in extract phase.This presented flexible method can fabricate some functionalized microparticles in our future work.展开更多
Double emulsions have been extensively used in scientific researches and industrial applications due to their attractive unique feature of multiple phases.However,constructing droplets with such a complex structure is...Double emulsions have been extensively used in scientific researches and industrial applications due to their attractive unique feature of multiple phases.However,constructing droplets with such a complex structure is not a simple task for all time.The simultaneous existence of two contradictory interfaces makes it hard to prepare stable double emulsions in principle and in practice.Over the past century,tremendous efforts have been devoted by myriads of scientists to make progresses in both theory and preparation of double emulsions.In this review,the current understanding of double emulsions is systematically revealed.In addition to emphasizing the corresponding pioneer and landmark works as many as possible,the state-of-the-art achievements will also be discussed.By regulating the oil-water interface with smartly designed interface-active agents in combination with varying the phase volume fractions,the basic theory framework based on the phase inversion from simple emulsions to double emulsions is also summarized.Technical preparation strategies of emulsification are introduced to show the building process of the two contradictory interfaces in one system.Furthermore,some specific biomedical applications of double emulsions are also discussed,which is expected to stimulate further innovation and utilization of double emulsions.展开更多
Pickering emulsions have been widely used for biphasic catalysis in the past decade.However,it remains a great challenge to achieve simple product collection and enzyme recovery.Poly(N-isopropylacrylamide)(PNIPAM)-bas...Pickering emulsions have been widely used for biphasic catalysis in the past decade.However,it remains a great challenge to achieve simple product collection and enzyme recovery.Poly(N-isopropylacrylamide)(PNIPAM)-based microgels can endow Pickering emulsions with stimuli-responsiveness,while most microgelstabilized emulsions are oil-in-water(O/W)type and not ideal for interfacial catalysis.Besides,altering temperature or pH value for demulsification is time-and energy-consuming and may cause irreversible deactivation of enzymes.In this work,inverse water-in-oil(W/O)Pickering emulsions were formed using hexanoic acidswollen microgels as the sole emulsifiers.When lipase was added in the water phase,stable oil-in-water-in-oil(O/W/O)Pickering double emulsions could be formed through one-step emulsification,owing to the synergistic effect of the hydrophobic microgels and hydrophilic lipase at the interface.Compared with other biphasic systems,such double emulsion systems represent a desirable platform for highly efficient biodiesel production because of the ultra-high interfacial areas and fast mass transport between two phases.More importantly,the switchable transition between hydrophobicity/hydrophilicity of microgels is controlled by the catalytic reaction.Therefore,double emulsions demulsify spontaneously when substrates are used up without the need for energy input or loss of enzymatic activity,enabling the facile collection of products and demonstrating the excellent recyclability of the biphasic catalysis system.展开更多
基金Supported by the National Natural Scientific Foundation of China(No.50472069)the Key Scientific Project from the Chinese Education Ministry(No.106100)
文摘Solid lipid nanoparticles loaded with bovine serum albumin（BSA） were prepared by a double emulsion method. As the mass fraction of the model drug BSA increased from 0 to 15%, the particle size gradually increased. The physical stability of the nanoparticles was investigated by zeta potential measurement and they were shown to be quite stable. Fluorescence spectroscopy confirmed that the loaded position of BSA was on the interface between the inner aqueous phase and the solid lipid phase. Both Fourier-transform infrared spectroscopy and circular dichroism spectra indicate that BSA in the nanoparticles was not destroyed, but the secondary structure was disrupted slightly.
基金This work is supported by the Natural Science Foundation of Hebei Province(Grant No.E20160203385)the Heavy Machinery Collaborative Innovation Program(Grant No.ZX01-20140400-05)。
文摘With the benefit fierce competition in the steel industry market in recent years,double cold reduction products have been developed towards strength improvement and thickness reduction.The traditional cold-rolling lubrication process with a fixed flow rate and concentration cannot solve the problems,which are uncontrollable plate shape and the excessive consumption of lubricating oil.Moreover,based on the analysis of the traditional direct aplication lubrication system of double cold reduction mill,a set of design scheme suitable for the emulsion pipeline direct mixing lubrication system of double cold reduction mill unit was proposed.The design completed the selection of key components,which included the static mixer and atomization nozzle selection,pump and oil pump design selection,pipeline design selection,flow type selection,pressure gauge selection,electronic control cabinet design selection and other eight aspects.Equipment of the emulsion pipeline direct mixing lubrication system of double cold reduction has been developed.Comparing with characteristics of the traditional direct aplication lubrication system,the emulsion pipeline direct mixing lubrication system was better applied to the production practice of a 1220 double cold reduction mill.The consumption of ton of steel was reduced by 9.6%.The rolling energy consumption and fuel consumption comprehensive costs decreased by 10.7%,and the strip steel section thickness difference was reduced by 19.3%.In addition,the plate shape quality defect rate decreased by 25.6%,otherwise creating a large economic benefit for the unit and promoting the application value.
文摘Insulin entrapped nanocapsules to use polylactide （PLA） as the encapsulating material were prepared through a modified water-in-oil-in-water （W/O/W） emulsification and solvent evaporation method, The average particle size of PLA nanocapsules obtained was decreased to （181.5 ± 8.4） nm, and capably adjusted from 180 to 370 nm by using different types and content of nonionic emulsifiers. The influence of emulsifiers on property of nanocapsules was discussed in detail. The effects of spans and tweens to modify the size of the nanocapsules were different, which can be due to the distribution of the surfactants on the inner interface between the inner water and oil of the double emulsion. The encapsulation efficiency and drug release of nanocapsules were affected obviously by the content and type of emulsifiers.
基金financially supported by the National Natural Science Foundation of China(No.50633030,Innovation Group:50921062)
文摘In this work, monodisperse giant polymersomes are fabricated by dewetting of water-in-oil-in-water double emulsion droplets which are assembled by amphiphilic block copolymer molecules in a microfluidic device. The dewetting process can be tuned by solvation between solvent and amphiphilic block copolymer to get polymersomes with controllable morphology. Good solvent （chloroform and toluene） hinders dewetting process of double emulsion droplets and gets acornlike polymersomes or patched polymersomes. On the other hand, poor solvent （hexane） accelerates the dewetting process and achieves complete separation of inner water phase from oil phase to form complete bilayer polymersomes. In addition, twin polymersomes with bilayer membrane structure are formed by this facile method. The formation mechanism for different polymersomes is discussed in detail.
基金the National Natural Science Foundation of China(Nos.21336010 and 81772417)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA16021400).
文摘A scalable and versatile strategy was developed for the fabrication of uniform polymeric microspheres with controllable interconnected porous structures. Uniform water-in-oil-in-water emulsions with linear poly(methyl methacrylate-glycidyl methacrylate) in the oil phase were generated by two-step premix membrane emulsification and used for constructing the microspheres. During the emulsion solidification process, internal water droplets were packed densely together, forming a thin oil film between the internal and external water phases. After solvent diffusion, the thin film can be ruptured and pores can be templated from the internal water droplets to form interconnected porous structures. Membranes with various pore sizes were obtained. The osmotic pressure and Laplace pressure balance were used to control the porosity and pore size precisely. The proposed method enables the fabrication of functional polymeric microspheres with uniform and controllable porous structures and particle sizes. This improves their performance and broadens the scope of their applications, especially in chromatographic separation.
文摘An easy method is presented to fabricate monodisperse magnetic macroporous polymer beads（MMPBs）. Waterin-oil high internal phase emulsion（HIPE） is prepared by emulsifying aqueous iron ions solution in an oil phase containing monomers. The HIPE is introduced into a simple microfluidic device to fabricate monodisperse（water-in-oil）-in-water double emulsion droplets. The droplets serve as microreactors to synthesize Fe3O4 nanoparticles and are on-line polymerized to form MMPBs. The prepared MMPBs display uniform size, interconnected porous structure, superparamagnetic behavior and uniform distribution of Fe3O4 in polymer matrix. The MMPBs are characterized by scanning electron microscopy（SEM）, Fourier transform infrared spectroscopy（FTIR）, X-ray diffraction（XRD）, transmission electron microscopy（TEM）, vibrating sample magnetometry（VSM）. We believe that this method is a universal technique in preparing macroporous nanocomposite beads.
基金supported by the National Natural Science Foundation of China(21435002,21621003)the National Key R&D Program of China(2017YFC0906800)
文摘This article presents sequential inkjet-based method to produce double emulsions as templates to fabricate morphology-controlled and inner-modified hole-shell microparticles. This sequential printing strategy for producing double emulsions circumvents complex wettability modification of the microchannels in lithography-based microfluidic device and largely saves the reagent in comparison to the coaxial two-phase jet in glass capillary. The formation of hole-shell structures is attributed to the diffusion of solvent out of droplets into butanol at the interface between oil and extract phase. The change of hole size is controlled by different diffusion rate, which is determined by changing the volume ratio of butanol and alcohol in extract phase.This presented flexible method can fabricate some functionalized microparticles in our future work.
基金This work was supported by the National Natural Science Foundation of China(Nos.21825503 and 21674127).
文摘Double emulsions have been extensively used in scientific researches and industrial applications due to their attractive unique feature of multiple phases.However,constructing droplets with such a complex structure is not a simple task for all time.The simultaneous existence of two contradictory interfaces makes it hard to prepare stable double emulsions in principle and in practice.Over the past century,tremendous efforts have been devoted by myriads of scientists to make progresses in both theory and preparation of double emulsions.In this review,the current understanding of double emulsions is systematically revealed.In addition to emphasizing the corresponding pioneer and landmark works as many as possible,the state-of-the-art achievements will also be discussed.By regulating the oil-water interface with smartly designed interface-active agents in combination with varying the phase volume fractions,the basic theory framework based on the phase inversion from simple emulsions to double emulsions is also summarized.Technical preparation strategies of emulsification are introduced to show the building process of the two contradictory interfaces in one system.Furthermore,some specific biomedical applications of double emulsions are also discussed,which is expected to stimulate further innovation and utilization of double emulsions.
基金Hong Kong Special Administrative Region(HKSAR)General Research Fund of The Chinese University of Hong Kong,Grant/Award Numbers:CUHK14304619,2130642National Natural Science Foundation of China,Grant/Award Number:32172347Natural Science Foundation of Guangdong Province,Grant/Award Number:2021A1515011000。
文摘Pickering emulsions have been widely used for biphasic catalysis in the past decade.However,it remains a great challenge to achieve simple product collection and enzyme recovery.Poly(N-isopropylacrylamide)(PNIPAM)-based microgels can endow Pickering emulsions with stimuli-responsiveness,while most microgelstabilized emulsions are oil-in-water(O/W)type and not ideal for interfacial catalysis.Besides,altering temperature or pH value for demulsification is time-and energy-consuming and may cause irreversible deactivation of enzymes.In this work,inverse water-in-oil(W/O)Pickering emulsions were formed using hexanoic acidswollen microgels as the sole emulsifiers.When lipase was added in the water phase,stable oil-in-water-in-oil(O/W/O)Pickering double emulsions could be formed through one-step emulsification,owing to the synergistic effect of the hydrophobic microgels and hydrophilic lipase at the interface.Compared with other biphasic systems,such double emulsion systems represent a desirable platform for highly efficient biodiesel production because of the ultra-high interfacial areas and fast mass transport between two phases.More importantly,the switchable transition between hydrophobicity/hydrophilicity of microgels is controlled by the catalytic reaction.Therefore,double emulsions demulsify spontaneously when substrates are used up without the need for energy input or loss of enzymatic activity,enabling the facile collection of products and demonstrating the excellent recyclability of the biphasic catalysis system.
