Microspheres Ⅰ,Ⅱ and Ⅲ were produced by emulsion technique.Microsphere I was solidified by glutaraldehyde crosslinking,microsphere Ⅱ was solidified by glutaraldehyde crosslinking and further treated with glycine s...Microspheres Ⅰ,Ⅱ and Ⅲ were produced by emulsion technique.Microsphere I was solidified by glutaraldehyde crosslinking,microsphere Ⅱ was solidified by glutaraldehyde crosslinking and further treated with glycine solution and microsphere Illwas solidified by heating denaturation only.The results showed that the microsphere diameter produced by cross[inking was bigger than that prepared by heating.The microsphere Ⅱ had higher hydrophilicity than Microsphere I had.The methotrexate (MTX) contents in microspheres Ⅰ and Ⅱ were 2.73±0.053%,2.87±0.119% respectively. microsphere Ⅲ was only blank microspheres with MTX adsorbed on their surfaces.In vitro release studies,microspheres I and I have maintained sustained release of MTX till the next day,it was found that the drug releases from microspheres Ⅰ and Ⅱ were governed by Higuchi diffusion law.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
Carbon capture is widely recognised as an essential strategy to meet global goals for climate protection.Although various C02 capture technologies including absorption,adsorption and membrane exist,they are not yet ma...Carbon capture is widely recognised as an essential strategy to meet global goals for climate protection.Although various C02 capture technologies including absorption,adsorption and membrane exist,they are not yet mature for post-combustion power plants mainly due to high energy penalty.Hence researchers are concentrating on developing non-aqueous solvents like ionic liquids,C 02-binding organic liquids,nanoparticle hybrid materials and microencapsulated sorbents to minimize the energy consumption for carbon capture.This research aims to develop a novel and efficient approach by encapsulating sorbents to capture C02 in a cold environment.The conventional emulsion technique was selected for the microcapsule formulation by using 2-amino-2-methyl-l-propanol(AMP)as the core sorbent and silicon dioxide as the shell.This paper reports the findings on the formulated microcapsules including key formulation parameters,microstructure,size distribution and thermal cycling stability.Furthermore,the effects of microcapsule quality and absorption temperature on the C02 loading capacity of the microcapsules were investigated using a self-developed pressure decay method.The preliminary results have shown that the AMP microcapsules are promising to replace conventional sorbents.展开更多
Porous silica prepared by using an acrylic emulsion has been impregnated with bismuth ion resulting in Bi2Si05 species containing surface. The as-prepared materials have been characterized by X-ray diffraction spectro...Porous silica prepared by using an acrylic emulsion has been impregnated with bismuth ion resulting in Bi2Si05 species containing surface. The as-prepared materials have been characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and N2 adsorption/desorption techniques. EDAX analysis confirms the penetration of bismuth ions into the framework of silica to form Bi2SiO5, which is substantiated by XRD. The UV-Vis DRS shows that the catalysts are optically active and XPS confirms the inclusion of bismuth into the framework of silica. FTIR spectra illustrate the formation of Bi-O-Si linkages in the porous silica framework. SEM and TEM show the spherical morphology, whereas N2 adsorption/desorption study confirms the porosity of the prepared materials. The photocatalytic activity of the material is evaluated for the degradation of isoproturon herbicide and it is found that the material is active as compared to the commercial P-25 Degussa TiO2.展开更多
文摘Microspheres Ⅰ,Ⅱ and Ⅲ were produced by emulsion technique.Microsphere I was solidified by glutaraldehyde crosslinking,microsphere Ⅱ was solidified by glutaraldehyde crosslinking and further treated with glycine solution and microsphere Illwas solidified by heating denaturation only.The results showed that the microsphere diameter produced by cross[inking was bigger than that prepared by heating.The microsphere Ⅱ had higher hydrophilicity than Microsphere I had.The methotrexate (MTX) contents in microspheres Ⅰ and Ⅱ were 2.73±0.053%,2.87±0.119% respectively. microsphere Ⅲ was only blank microspheres with MTX adsorbed on their surfaces.In vitro release studies,microspheres I and I have maintained sustained release of MTX till the next day,it was found that the drug releases from microspheres Ⅰ and Ⅱ were governed by Higuchi diffusion law.
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.
文摘Carbon capture is widely recognised as an essential strategy to meet global goals for climate protection.Although various C02 capture technologies including absorption,adsorption and membrane exist,they are not yet mature for post-combustion power plants mainly due to high energy penalty.Hence researchers are concentrating on developing non-aqueous solvents like ionic liquids,C 02-binding organic liquids,nanoparticle hybrid materials and microencapsulated sorbents to minimize the energy consumption for carbon capture.This research aims to develop a novel and efficient approach by encapsulating sorbents to capture C02 in a cold environment.The conventional emulsion technique was selected for the microcapsule formulation by using 2-amino-2-methyl-l-propanol(AMP)as the core sorbent and silicon dioxide as the shell.This paper reports the findings on the formulated microcapsules including key formulation parameters,microstructure,size distribution and thermal cycling stability.Furthermore,the effects of microcapsule quality and absorption temperature on the C02 loading capacity of the microcapsules were investigated using a self-developed pressure decay method.The preliminary results have shown that the AMP microcapsules are promising to replace conventional sorbents.
基金PAKR and MS thank CSIR,New Delhi for funding this work under Emeritus Scientist Scheme
文摘Porous silica prepared by using an acrylic emulsion has been impregnated with bismuth ion resulting in Bi2Si05 species containing surface. The as-prepared materials have been characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and N2 adsorption/desorption techniques. EDAX analysis confirms the penetration of bismuth ions into the framework of silica to form Bi2SiO5, which is substantiated by XRD. The UV-Vis DRS shows that the catalysts are optically active and XPS confirms the inclusion of bismuth into the framework of silica. FTIR spectra illustrate the formation of Bi-O-Si linkages in the porous silica framework. SEM and TEM show the spherical morphology, whereas N2 adsorption/desorption study confirms the porosity of the prepared materials. The photocatalytic activity of the material is evaluated for the degradation of isoproturon herbicide and it is found that the material is active as compared to the commercial P-25 Degussa TiO2.