An effective vaccine against group A streptococcus(GAS)is highly desirable for definitive control of GAS infections.In the present study,two variants of amphiphilic chitosan nanoparticles-based GAS vaccines were devel...An effective vaccine against group A streptococcus(GAS)is highly desirable for definitive control of GAS infections.In the present study,two variants of amphiphilic chitosan nanoparticles-based GAS vaccines were developed.The vaccines were primarily composed of encapsulated KLH protein(a source of T helper cell epitopes)and lipidated M-protein derived B cell peptide epitope(lipoJ14)within the amphiphilic structure of nanoparticles.The only difference between themwas one of the nanoparticles vaccines received additional surface coating with poly(I:C).The formulated vaccines exhibited nanosized particles within the range of 220–240 nm.Cellular uptake study showed that nanoparticles vaccine without additional poly(I:C)coating has greater uptake by dendritic cells and macrophages compared to nanoparticles vaccine that was functionalized with poly(I:C).Both vaccines were found to be safe in mice and showed negligible cytotoxicity against HEK293 cells.Upon immunization in mice,both nanoparticle vaccines produced high antigen-specific antibodies titres that were regulated by a balanced Th1 and Th2 response compared to physical mixture.These antibodies elicited high opsonic activity against the tested GAS strains.Overall,our data demonstrated that amphiphilic chitosan nanoparticles platform induced a potent immune response even without additional inclusion of poly(I:C).展开更多
A novel method was presented to create composite micelles of amphiphilic copolymers and Ag nanoparticles(NPs) in a three-dimensional co-flow focusing microfluidic device(3D CFMD). Self-assembly of the copolymers was i...A novel method was presented to create composite micelles of amphiphilic copolymers and Ag nanoparticles(NPs) in a three-dimensional co-flow focusing microfluidic device(3D CFMD). Self-assembly of the copolymers was initiated by the fast mixing of water and a blend dispersion of hydrophobic Ag NPs and amphiphilic copolymers. At the same time, the hydrophobic Ag NPs enter the core of copolymer micelles, based on the hydrophobic interaction. The copolymer-Ag NPs composite micelles have a core-shell structure with copolymer shell and Ag NPs core. COMSOL Multiphysics is used to simulate the concentration distribution of copolymers and Ag NPs under different flow rates. Co-assembly microfluidic conditions are determined based on simulation results. Under suitable microfluidic conditions, both block copolymers and gradient copolymers can co-assemble with hydrophobic Ag NPs to form composite micelles, respectively. This microfluidic coassembly method will have a good prospect in the preparation of composite micelles of amphiphilic copolymers and metal nanoparticles.展开更多
Conversion and capture of carbon pollutants based on carbon dioxide to valuable green oil-field chemicals are target all over the world for controlling the global warming.The present article used new room temperature ...Conversion and capture of carbon pollutants based on carbon dioxide to valuable green oil-field chemicals are target all over the world for controlling the global warming.The present article used new room temperature amphiphilic imidazolium ionic liquids with superior surface activity in the aqueous solutions to convert carbon dioxide gas to superior amphiphilic calcium carbonate nanoparticles.In this respect,tetra-cationic ionic liquids 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate and 2-(4-hexyldimethylamino)phenyl)-1,3-bis(3-hexcyldimethylammnonio)propyl)bromide-1 H-imidazol-3-ium acetate were prepared.Their chemical structures,thermal as well as their carbon dioxide absorption/desorption characteristicswere evaluated.Theywere used as solvent and capping agent to synthesize calcium carbonate nanoparticles with controlled crystalline lattice,sizes,thermal properties and spherical surface morphologies.The prepared calcium carbonate nanoparticles were used as additives for the commercial water based drilling mud to improve their filter lose and rheology.The data confirm that the lower concentrations of 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate achieved lower seawater filter lose and improved viscosities.展开更多
Drug delivery by nanocarriers requires characterizations of suitable particle size, high drug loading and safety. In this work, we prepared an amphiphilic dendrimer modified PEG-PLA mixed nanoparticles（NPs） by a dou...Drug delivery by nanocarriers requires characterizations of suitable particle size, high drug loading and safety. In this work, we prepared an amphiphilic dendrimer modified PEG-PLA mixed nanoparticles（NPs） by a double emulsion-solvent evaporation（DESE） method. The particle size and drug encapsulation efficacy（EE） were compared to evaluate and optimize the preparation parameters. The mixed NPs had average size ranging from（102±1） nm to（137±5） nm, and the zeta potential turned to positive with incorporation of the amphiphilic dendrimer. The NPs showed different EE of docetaxel（DTX） and paclitaxel（PTX） with higher affinity to more lipophilic PTX. The blank mixed NPs showed little cytotoxicity, and the DTX-loaded NPs could effectively facilitate the antiproliferation activity on PC-3 cells. The NPs could be used as an effective drug delivery system, and its anti-tumor effect is worthy of further study.展开更多
Oleanolic acid(OA)is a pentacyclic triterpenoid compound with extensive biological effects,such as anti-inflammatory and anticancer activities.However,the application of OA in chemotherapy is hampered by its poor solu...Oleanolic acid(OA)is a pentacyclic triterpenoid compound with extensive biological effects,such as anti-inflammatory and anticancer activities.However,the application of OA in chemotherapy is hampered by its poor solubility and severe adverse effects.To solve the problems,we developed a self-assembled nanoparticle platform based on amphiphilic oleanolic acid polyprodrug,poly[oligo(ethylene glycol)methyl ether methacrylate]-b-poly(oleanolic acid methacrylate)(POEGMA-b-POAMA),encapsulating 10-hydroxycamptothecin(HCPT)to achieve efficient cancer therapy.The polyprodrug was prepared via reversible addition-fragmentation chain transfer polymerization(RAFT),and could selfassemble to prepare POEGMA-b-POAMA/HCPT nanoparticles(NPs).The obtained nanoparticles exhibited appropriate particle size,excellent drug stability,good drug loading capacity,and high drug loading efficiency.In vitro drug release indicated that the drug release was prolonged to 132 h.The POEGMA-b-POAMA/HCPT NPs enhanced cell cytotoxicity in 4T1 cells and MCF-7 cells and could be efficiently uptaken by 4T1 cells.Furthermore,in vivo antitumor efficiency showed that the POEGMA-b-POAMA/HCPT NPs had great antitumor efficiency with considerably low adverse effects in the treatment of the 4T1 mouse breast tumor xenograft tumor.Therefore,POEGMA-b-POAMA/HCPT NPs provide great potential as a platform for drug delivery applications.展开更多
Membrane modification is one of the most feasible and effective solutions to membrane fouling proble.m which tenaciousl.y hampers .the furher au .gmentation of me .rnbrane sep.aration technology.Blending modification ...Membrane modification is one of the most feasible and effective solutions to membrane fouling proble.m which tenaciousl.y hampers .the furher au .gmentation of me .rnbrane sep.aration technology.Blending modification with nanoparticles （NPs）, owing to the convenience of being incorporated in established membrane.p.rodu. ction lines, possesses an advantag, eous viability in practical applications.However, the existing blending strategy suffers from a low utilization efficiency due to NP encasement by membrane matrix. The current study proposed an improved blending modification approach with amphiphilic NPs （aNPs）, which were prepared through silanization using 3-（Trimethoxysilyl）propyl methacrylate （TMSPMA） as coupling agents and ZnO or SiO2 as pristine NPs （pNPs）, respectively.The Fourier transform infrared and X-ray photoelectron spectroscopy analyses revealed thepresence of appropriate organic components in both the ZnO and SiO2 aNPs, which verified the success of the silanization process. As compared with the pristine and conventional pNP-blended membranes, both the ZnO aNP-blended and SiO2 aNP-blended membranes with proper silanization （100% and 200% w/w） achieved a significantly increased blending efficiency with more NPs scattenng on the internal and external membrane surfaces under scanning electron microscope observation. This improvement contributed to the increase of membrane hydrophilicity. Nevertheless, an extra dosage of the TMSPMA led to an encasement of NPs, thereby adversely affecting the properties of the resultant membranes. On the basis of all the tests, 100% （w/w） was selected as the optimum TMSPMA dosage for blending modification for both the ZnO and SiO2 types.展开更多
通过Pickering乳液模板法对硅烷化的SiO_2纳米颗粒的部分表面进行氟化改性,制备出两亲SiO_2纳米颗粒,并研究其在气/液表面上的自组装行为和泡沫性能。采用粒径分析仪、傅里叶变换红外光谱仪(FTIR)、表面张力仪、扫描电镜(SEM)和动态泡...通过Pickering乳液模板法对硅烷化的SiO_2纳米颗粒的部分表面进行氟化改性,制备出两亲SiO_2纳米颗粒,并研究其在气/液表面上的自组装行为和泡沫性能。采用粒径分析仪、傅里叶变换红外光谱仪(FTIR)、表面张力仪、扫描电镜(SEM)和动态泡沫分析仪对两亲SiO_2纳米颗粒的粒径分布、化学组成、界面活性、石蜡乳滴的表面形貌和泡沫性能进行分析表征。结果表明:采用Stber方法合成的SiO_2纳米颗粒的平均粒径为104 nm;氨丙基三乙氧基硅烷(APTES)处理后的SiO_2纳米颗粒在石蜡乳滴上排列的更加紧密有序,提高了改性效率;当两亲SiO_2纳米颗粒浓度达到0.6%时,两亲SiO_2纳米颗粒在界面上的吸附达到饱和,此时表面张力平衡值下降到32.7 m N/m,展现出良好的界面活性;泡沫性能测试结果表明,两亲颗粒有效地抑制了气泡合并、歧化作用和液膜排液,制备的泡沫具有良好的稳定性。展开更多
基金supported financially by Universiti Kebangsaan Malaysia(UKM),Malaysia[DCP-2017-003/2].
文摘An effective vaccine against group A streptococcus(GAS)is highly desirable for definitive control of GAS infections.In the present study,two variants of amphiphilic chitosan nanoparticles-based GAS vaccines were developed.The vaccines were primarily composed of encapsulated KLH protein(a source of T helper cell epitopes)and lipidated M-protein derived B cell peptide epitope(lipoJ14)within the amphiphilic structure of nanoparticles.The only difference between themwas one of the nanoparticles vaccines received additional surface coating with poly(I:C).The formulated vaccines exhibited nanosized particles within the range of 220–240 nm.Cellular uptake study showed that nanoparticles vaccine without additional poly(I:C)coating has greater uptake by dendritic cells and macrophages compared to nanoparticles vaccine that was functionalized with poly(I:C).Both vaccines were found to be safe in mice and showed negligible cytotoxicity against HEK293 cells.Upon immunization in mice,both nanoparticle vaccines produced high antigen-specific antibodies titres that were regulated by a balanced Th1 and Th2 response compared to physical mixture.These antibodies elicited high opsonic activity against the tested GAS strains.Overall,our data demonstrated that amphiphilic chitosan nanoparticles platform induced a potent immune response even without additional inclusion of poly(I:C).
基金Funded by the National Natural Science Foundation of China(Nos.51873167 and 50803048)
文摘A novel method was presented to create composite micelles of amphiphilic copolymers and Ag nanoparticles(NPs) in a three-dimensional co-flow focusing microfluidic device(3D CFMD). Self-assembly of the copolymers was initiated by the fast mixing of water and a blend dispersion of hydrophobic Ag NPs and amphiphilic copolymers. At the same time, the hydrophobic Ag NPs enter the core of copolymer micelles, based on the hydrophobic interaction. The copolymer-Ag NPs composite micelles have a core-shell structure with copolymer shell and Ag NPs core. COMSOL Multiphysics is used to simulate the concentration distribution of copolymers and Ag NPs under different flow rates. Co-assembly microfluidic conditions are determined based on simulation results. Under suitable microfluidic conditions, both block copolymers and gradient copolymers can co-assemble with hydrophobic Ag NPs to form composite micelles, respectively. This microfluidic coassembly method will have a good prospect in the preparation of composite micelles of amphiphilic copolymers and metal nanoparticles.
基金supported by Science,Technology&Innovation Funding Authority(STDF)under grant(No.47062).
文摘Conversion and capture of carbon pollutants based on carbon dioxide to valuable green oil-field chemicals are target all over the world for controlling the global warming.The present article used new room temperature amphiphilic imidazolium ionic liquids with superior surface activity in the aqueous solutions to convert carbon dioxide gas to superior amphiphilic calcium carbonate nanoparticles.In this respect,tetra-cationic ionic liquids 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate and 2-(4-hexyldimethylamino)phenyl)-1,3-bis(3-hexcyldimethylammnonio)propyl)bromide-1 H-imidazol-3-ium acetate were prepared.Their chemical structures,thermal as well as their carbon dioxide absorption/desorption characteristicswere evaluated.Theywere used as solvent and capping agent to synthesize calcium carbonate nanoparticles with controlled crystalline lattice,sizes,thermal properties and spherical surface morphologies.The prepared calcium carbonate nanoparticles were used as additives for the commercial water based drilling mud to improve their filter lose and rheology.The data confirm that the lower concentrations of 2-(4-dodecyldimethylamino)phenyl)-1,3-bis(3-dodecyldimethylammnonio)propyl)bromide-1-H-imidazol-3-ium acetate achieved lower seawater filter lose and improved viscosities.
基金National Natural Science Foundation of China(Grant No.81473156,81673365,81273454)Doctoral Foundation of the Ministry of Education(Grant No.20130001110055)National Key Basic Research Program(Grant No.2013CB932501)
文摘Drug delivery by nanocarriers requires characterizations of suitable particle size, high drug loading and safety. In this work, we prepared an amphiphilic dendrimer modified PEG-PLA mixed nanoparticles（NPs） by a double emulsion-solvent evaporation（DESE） method. The particle size and drug encapsulation efficacy（EE） were compared to evaluate and optimize the preparation parameters. The mixed NPs had average size ranging from（102±1） nm to（137±5） nm, and the zeta potential turned to positive with incorporation of the amphiphilic dendrimer. The NPs showed different EE of docetaxel（DTX） and paclitaxel（PTX） with higher affinity to more lipophilic PTX. The blank mixed NPs showed little cytotoxicity, and the DTX-loaded NPs could effectively facilitate the antiproliferation activity on PC-3 cells. The NPs could be used as an effective drug delivery system, and its anti-tumor effect is worthy of further study.
基金This work was financially supported by the National Natural Science Foundation of China(No.21576029)National Key R&D Program of China(No.2017YFD0601205).
文摘Oleanolic acid(OA)is a pentacyclic triterpenoid compound with extensive biological effects,such as anti-inflammatory and anticancer activities.However,the application of OA in chemotherapy is hampered by its poor solubility and severe adverse effects.To solve the problems,we developed a self-assembled nanoparticle platform based on amphiphilic oleanolic acid polyprodrug,poly[oligo(ethylene glycol)methyl ether methacrylate]-b-poly(oleanolic acid methacrylate)(POEGMA-b-POAMA),encapsulating 10-hydroxycamptothecin(HCPT)to achieve efficient cancer therapy.The polyprodrug was prepared via reversible addition-fragmentation chain transfer polymerization(RAFT),and could selfassemble to prepare POEGMA-b-POAMA/HCPT nanoparticles(NPs).The obtained nanoparticles exhibited appropriate particle size,excellent drug stability,good drug loading capacity,and high drug loading efficiency.In vitro drug release indicated that the drug release was prolonged to 132 h.The POEGMA-b-POAMA/HCPT NPs enhanced cell cytotoxicity in 4T1 cells and MCF-7 cells and could be efficiently uptaken by 4T1 cells.Furthermore,in vivo antitumor efficiency showed that the POEGMA-b-POAMA/HCPT NPs had great antitumor efficiency with considerably low adverse effects in the treatment of the 4T1 mouse breast tumor xenograft tumor.Therefore,POEGMA-b-POAMA/HCPT NPs provide great potential as a platform for drug delivery applications.
文摘Membrane modification is one of the most feasible and effective solutions to membrane fouling proble.m which tenaciousl.y hampers .the furher au .gmentation of me .rnbrane sep.aration technology.Blending modification with nanoparticles （NPs）, owing to the convenience of being incorporated in established membrane.p.rodu. ction lines, possesses an advantag, eous viability in practical applications.However, the existing blending strategy suffers from a low utilization efficiency due to NP encasement by membrane matrix. The current study proposed an improved blending modification approach with amphiphilic NPs （aNPs）, which were prepared through silanization using 3-（Trimethoxysilyl）propyl methacrylate （TMSPMA） as coupling agents and ZnO or SiO2 as pristine NPs （pNPs）, respectively.The Fourier transform infrared and X-ray photoelectron spectroscopy analyses revealed thepresence of appropriate organic components in both the ZnO and SiO2 aNPs, which verified the success of the silanization process. As compared with the pristine and conventional pNP-blended membranes, both the ZnO aNP-blended and SiO2 aNP-blended membranes with proper silanization （100% and 200% w/w） achieved a significantly increased blending efficiency with more NPs scattenng on the internal and external membrane surfaces under scanning electron microscope observation. This improvement contributed to the increase of membrane hydrophilicity. Nevertheless, an extra dosage of the TMSPMA led to an encasement of NPs, thereby adversely affecting the properties of the resultant membranes. On the basis of all the tests, 100% （w/w） was selected as the optimum TMSPMA dosage for blending modification for both the ZnO and SiO2 types.
文摘通过Pickering乳液模板法对硅烷化的SiO_2纳米颗粒的部分表面进行氟化改性,制备出两亲SiO_2纳米颗粒,并研究其在气/液表面上的自组装行为和泡沫性能。采用粒径分析仪、傅里叶变换红外光谱仪(FTIR)、表面张力仪、扫描电镜(SEM)和动态泡沫分析仪对两亲SiO_2纳米颗粒的粒径分布、化学组成、界面活性、石蜡乳滴的表面形貌和泡沫性能进行分析表征。结果表明:采用Stber方法合成的SiO_2纳米颗粒的平均粒径为104 nm;氨丙基三乙氧基硅烷(APTES)处理后的SiO_2纳米颗粒在石蜡乳滴上排列的更加紧密有序,提高了改性效率;当两亲SiO_2纳米颗粒浓度达到0.6%时,两亲SiO_2纳米颗粒在界面上的吸附达到饱和,此时表面张力平衡值下降到32.7 m N/m,展现出良好的界面活性;泡沫性能测试结果表明,两亲颗粒有效地抑制了气泡合并、歧化作用和液膜排液,制备的泡沫具有良好的稳定性。
