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An Optical Sensor Based on Polyvinyl Benzyl Malonate Cross-Linked with Divinyl Benzene Dispersed in a Hydrogel Membrane for Detection of Some Heavy Metals

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American Journal of Analytical Chemistry 2012年第4期3卷 283-287页

作者： Imad Odeh Ziad Shakhsher Suha Jaber Mahmood Khateeb Fuad Al-Rimawi Faculty of Science and Technology Al-Quds University East Jerusalem Palestine

In previous work we have developed a dicarboxylate functionalized polymer that demonstrated chemical sensing. It showed good response to pH changes as well as to varying concentrations of copper and calcium ions. Our recent in-vest- tigations showed interesting results upon testing the functionalized sensing polymer on heavy metals. This sensor is composed of microspheres of polyvinyl benzyl malonate lightly-cross-linked with divinyl benzene dispersed in a hydrogel membrane. The response of the optical sensor is based on the interaction between the metal cations with the deprotonated functional group. The polymer, thus, undergoes shrinking as a result of neutralization of adjacent negative charges on the back-bone of the polymer. This causes significant changes in the optical properties of the sensing element. The optical changes were measured as absorbance vs. wavelength as the sensing membrane is exposed to solutions of varying concentrations of heavy metal ions. The sensor showed significant increase in absorbance up to a concentration of 5 × 10-3 M to the following metal ions: Ni2+, Zn2+, and Cd2+. Furthermore, the studied capacity of the derivatized microspheres showed close values to Ni2+, Zn2+, Cd2+ (1.20, 1.09, 1.08 mmol/g respectively). These kinds of properly functionalized polymers appear to be suitable, versatile sensing elements for the detection of low concentrations of heavy metal ions. In addition, all of the tested heavy metals showed a similar value of the equilibrium formation constant, (log Kf1 is 2.63). In contrast, the sensor showed no significant response to varying concentrations of K+ and Mg2+ metal ions.

关键词： Shrinking microsphere Polymer Polyvinylbenzylmalonate Optical Chemical Sensors Heavy Metal Sensing Equilibrium Formation Constant

Preparation and in vitro Release of Donepezil Hydrochloride microspheres

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Medicinal Plant 2018年第6期9卷 65-67页

作者： Yingzhou WANG Hao QI Dongze ZHANG Zixuan ZHAO Chunyan ZHANG School of Pharmacy Jining Medicinal College

[Objectives]To prepare donepezil hydrochloride microspheres and evaluate their quality.[Methods]The donepezil hydrochloride microspheres were prepared by emulsification-solvent evaporation method.The morphology was observed by scanning electron microscopy and the particle size distribution was determined by Laser Diffraction Method.The encapsulation efficiency,drug loading capacity,and in vitro release were determined by HPLC.[Results]The prepared donepezil hydrochloride microspheres were spherical with the average particle diameter of 15.927 μm.The drug loading capacity was 35.62%.The encapsulation efficiency was 90.32%.The drug release in vitro lasted for14 d.The release curve accorded with the first-order kinetic equation.[Conclusions]The prepared donepezil hydrochloride microspheres performed good sustained release effect in vitro,and it was expected to be used for research on Parkinson's disease.

关键词： Donepezil hydrochloride Polylactic acid-glycolic acid copolymer microsphere

Structural Assessment of microsphere-based Tissue Engineered Scaffold from Poly（lactic acid）/β-Tricalcium Phosphate

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Structural Assessment of Microsphere-based Tissue Engineered...

The 3～〔rd〕International Conference on High-Performance Ceramics(CICC-3)（2）

作者： Yingjun Wang Jianhua Ge Yudong Zheng Xiaohui Zhang Xiaofeng Chen Wei Ran and Gang WuKey Laboratory of Specially Functional Materials and Advanced Manufacturing Technology (South China University of Technology) Ministry of Education Guangzhou ChinaInstitute of Material Science and Engineering South China University of Technology Guangzhou 510640 P. R. China

＜正＞ The addition of β-tricalcium phosphate improves the biocompatibility and the bioactivity of scaffolds made from poly（lactic acid）（PLA）. In this paper, a developed method was used to prepare poly（lactic acid）/β-tricalcium phosphate microsphere-based tissue engineered scaffolds. It was found that the porosity and the compressive modulus of the scaffolds increased with increasing stirring time. The PLA scaffolds with a higher strength and porosity could be obtained under the optimum conditions （i.e., 2.0 g of PLA, 0.2 g of p-tricalcium phosphate, 300 rpm, stirring time for 2h ）. In addition, the corresponding mechanism has been discussed.

关键词： microsphere Tissue engineering scaffold Poly（lactic acid） p-tricalcium phosphate

Preparation and Characterization of Gelatin-Based bFGF-Impregnated microsphere

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Preparation and Characterization of Gelatin-Based bFGF-Impre...

加速功能材料自主创新，促进西部战略性新兴产业发展——2...

作者： Kangjian WANG1,2,Shiwei XIAO1,2,Yichun YE1,2,Nianhua DAN1,2,Yang HU1,2,Weihua DAN1,2 1 National Engineering Laboratory for Clean Technology of Leather Manufacture,Sichuan University,Chengdu,China,610065 2 Medical Biomaterials Laboratory for the Research Center of Biomedicine Engineering of Sichuan University,Chengdu,China,610065

The gelatin-based basic fibroblast growth factor(bFGF)-impregnated microspheres were prepared by emulsification and cold-condensation while glutaraldehyde was used as crosslinker.Scanning electronic microscope(SEM)and laser nano-granulometer were applied to analyze the characters of these particles.Meanwhile,the experiments of acute oral toxicity and proliferation of cells were carried out.The feasibility of introducing drug sustained-release microsphere system to the field of tissue engineering was discussed,which would establish the foundation for the application of combination use of gelatin/collagen-based wound-rehabilitation membranes as well as the preparation for further study of tissue engineering skin with inducement and regeneration function.

关键词： gelatin microsphere sustained-release characterization bFGF

聚乙烯醇空心微球的制备及其对尿素的缓释作用(英文)

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Agricultural Science & Technology 2008年第5期9卷 8-12,18页

作者：邵兵邱舒张文莉倪良邵怿王超江苏大学化学化工学院江苏镇江212013

[Objective] The aim of this study was to discuss the optimizing preparation conditions of polyvinyl alcohol(PVA)hollow microsphere and its application in the production of slow-release urea fertilizer.[Method]PVA hollow microsphere was prepared by the emulsion chemical cross-linking method,while its composition,morphology and particle size was analyzed by technologies of FT-IR,SEM and TEM respectively.Thus,factors such as rate of emulsified speed,crosslink temperature and linking agent amount with effects on morphology and particle size of hollow microsphere were also discussed in this study.Furthermore,based on the optimizing preparation conditions,PVA fertilizer carrier microsphere was prepared by coating urea to investigate its sustained release effect on urea.[Result]The optimizing preparation conditions of polyvinyl alcohol(PVA)hollow microsphere were as follows:rate of emulsified speed 6 000 r/min,crosslink temperature 35 ℃ and linking agent amount 25 ml.PVA fertilizer carrier microsphere had significant sustained release effect on urea,and the optimal cross-linking time was 3 hours.[Conclusion]This study provides theoretical basis for the development of new slow-release fertilizer.

关键词： Polyvinyl alcohol Hollow microsphere Emulsion chemical cross-linking Urea Sustained release effect

Preparation and in vitro release behaviour of Urapidil Hydrochloride Loading into microspheres based on PLLA

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Preparation and in vitro release behaviour of Urapidil Hydro...

The 5th Joint China/Japan Chemical Engineering Symposium

作者： Hao Hong~(1*) Zhao Tao Guan Xiaoyu School of Chemical Engineering Northwest University Xi’an 710069

＜正＞Poly（L-lactide）（PLLA） microspheres were prepared using different methods.The surface morphology and the size of the microspheres were observed by SEM.Meanwhile,the drug loading efficiency of microspheres and the in vitro release of urapidil hydrochloride from microspheres were performed.The urapidil hydrochloride-PLLA microspheres exhibited better sustained-release capacity.

关键词： urapidil hydrochloride poly（L-lactide）（PLLA） microsphere loading efficiency

houStudies on the effect ofalginate-chitosansustained releasemicrocapsules fortranshepatic arterial embolization in VX2 rabbit liver cancer model

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houStudies on the effect ofalginate-chitosansustained releas...

加快转变医药发展方式，占领科学技术制高点——2011年...

作者： Guang-YuZhang 1,Yang Liu,Xue-nong Zhang 1,Qiang Zhang 2 1 Department of Pharmaceutics,School of Pharmaceutical Science,Soochow University,Suzhou 215123,People''s Republic of China 2 Department of Pharmaceutics,School of Pharmaceutical Science,Peking University,Beijing 100083,People''s Republic of China

Purpose:To study the preparation technique of a sustained-released microsphere （LSD/NTCD-ACM） and evaluate its characteristic and effects for transarterial hepatic chemoembolization （TACE） in an animal model of liver cancer （VX2）.Mmethods:We prepared LSD/NTCD-ACM through the emulsification-gelation method with liquid paraffin as oil phase,the hybrid of chitosan and sodium alginate as water phase,Span-80 as emulsifier,and glutaraldehyde as cross linking agent.Studied its in vitro release in pH 7.4 PBS by dynamic dialysis method.Then 24 male New Zealand white rabbits were randomly divided into four groups with 6 rabbits assigned to each group.VX2 carcinoma tissues were implanted into the left hepatic lobe using a 16g biopsy gun.The tumors were allowed to grow for weeks,and studies were performed until the volume of the tumors detected by ultrasonograph reached 2-3 cm 3.Under anesthesia,transcatheter hepatic arterial embolization was performed and LSD/NTCD-ACM（60-120μm）,LSD/NTCD-ACM（120-200μm） or NCTD solution was injected into the hepatic arteries of animals in the three treatment groups and the left one is control group（with no treatment）.Before and at 3,7,14 days after injection,the volume of the tumor was measured by ultrasonograph,the serum of all rabbits was collected,and the level of aspartate aminotransferase （AST） was checked.During the last course of their disease,the rabbits were given analgesics to relieve suffering.The survival period of the three groups of rabbits after treatment was recorded,and degree of liver cell necrosis was also assessed on the histopathological specimens.Results:The drug entrapment efficiency （EE%） of LSD/NTCD-ACM（60-120μm） was 74.62% and drug-loading （DL%） amount was 7.46% while 86.93% for EE and 9.23%for DL of LSD/NTCD-ACM （120-200μm）.Both the two particles could release as long as 20 days in pH 7.4 PBS.The tumor growth rate in the LSD/NCTD-ACM （60-120/μm） group （7.76±0.41,tumor volume from2.48±0.25 to19.24±1.33 cm 3） and in the LSD/NCTD-ACM （120-200/μm） group （9.56±0.37,tumor

关键词： embolization VX2 necrosis microsphere NCTD alginate chitosan

聚乳酸-乙醇酸的直接合成及其在蛋白质传输系统中的应用（英文）

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聚乳酸-乙醇酸的直接合成及其在蛋白质传输系统中的应用（英文）

“以岭医药杯”第八届全国青年药学工作者最新科研成果交流...

作者：杨帆张永明宋凤兰潘育芳赵耀明汪朝阳梁世中徐安龙中山大学生命科学院中山大学生命科学院广东药学院药科学院广东药学院药科学院华南理工大学材料学院华南理工大学材料学院华南理工大学材料学院中山大学生命科学院

以等摩尔的L-乳酸,乙醇酸为原料,通过熔融聚合法直接合成生物降解材料聚乳酸-乙醇酸PLGA50／50。当在165℃, 70 Pa的条件下,以质量分数为0．5％的氯化亚锡为催化剂,熔融聚合10h,产物特性黏度最高可达0．1993 dL／g。以此条件下合成的聚... 详细信息

以等摩尔的L-乳酸,乙醇酸为原料,通过熔融聚合法直接合成生物降解材料聚乳酸-乙醇酸PLGA50／50。当在165℃, 70 Pa的条件下,以质量分数为0．5％的氯化亚锡为催化剂,熔融聚合10h,产物特性黏度最高可达0．1993 dL／g。以此条件下合成的聚乳酸-乙醇酸PLGA50／50为载体制备干扰素α-聚乳酸乙醇酸-微球（IFN-α—PLGA—MS）。通过正交实验对干扰素微球的制备工艺进行了优化,同时对微球的性质进行了考察。制得的IFN—α—PLGA—MS的载药量和包封率分别为8．06％和 36．97％。通过SEM观测可知,制得的微球形态圆整,表面光滑,有一些渗透性小孔,且粒径较均匀。超过85％的微球粒径都在40—60μm之间,平均粒径是58．92μm。DSC曲线显示,空白微球的吸热峰是1．2J／g,而干扰素微球的吸热峰是8．0J／g。载药微球吸热峰的增加表明,药物确实已被包裹在微球中而不是吸附在微球表面。IFN—α—PLGA—MS的体外释放表明,微球有很好的缓释效果,突释不是很明显,且在7天内的累积释放量可达60％。体外释放的Higuchi方程是y=0．4566t（?）+2．4623, r=0．9419。且IFN—α—MS的体外释放在一周内,其释放液都具有很好的生物活性。

关键词： biodegradable copolymerization melt synthesis Protein-Delivery Systems microsphere

Studies on sustained-release microspheres of triptorelin acetate

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Studies on sustained-release microspheres of triptorelin ace...

2018年第十二届中国药物制剂大会

作者： Li-Qing Chen Hao-Yan Huang 曹青日 College of Pharmaceutical Scicences Soochow University

Objective: To prepare sustained-release microspheres of triptorelin acetate and to evaluate the pharmaceutical properties of microspheres. Methods: The blank microspheres were prepared by a phase separation method with PLGA as sustained release carrier. The formulation and preparation process of blank microspheres were optimized in terms of particle size and surface morphology. The drug-loaded microspheres were prepared by dispersing the drug powder or drug-acetic acid solution into organic phase. The optimal formulation and preparation process of drug-loaded microspheres were screened on the basis of particle size and surface morphology as well as drug loading and encapsulation efficiency. The release study of commercial and prepared microspheres was performed in PBS-0.2% Tween 80（pH=7.4）, at 37℃ with a rotate speed of 100 rpm. Results: The blank microspheres prepared by PLGA from EVONIK Industries showed suitable particle size and surface morphology. The optimal formulation and preparation conditions of blank microspheres were as follows: the concentration of PLGA was 2.0%;the ratio of dichloromethane and simethicone was 2:1（w/w） and the ratio of simethicone and n-heptane was 1:30（w/v）;the stirring rate was 400 rpm and the stirring time was 30 min. Compared to the microspheres prepared by dispersing the drug powder into PLGA solution, the microspheres prepared by mixing the drug-acetic acid solution with PLGA solution showed higher drug loading and encapsulation efficiency, which improved from 0.49% to 1.69% and from 29.49% to 98.45%, respectively. But both of them presented similar particle size and surface morphology. The release profile of commercial microspheres showed that the initial release was about 20% and the release rate could reach up to 45% in four week. The release of prepared microspheres presented similar characteristics as the commercial microspheres. Conclusion: The sustained-release microspheres of triptorelin acetate prepared with the optimal formulation and preparation process was suitable

关键词： triptorelin acetate microsphere PLGA phase separation particle size surface morphology release