The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole （Ag-CMCTS-TBZ） prepared from different materiel ratios were reported. ...The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole （Ag-CMCTS-TBZ） prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.展开更多
Most seed gums have been widely used in oral and topical pharmaceutical formulations, cosmetics, and food products because of their hydrophilic properties. Gums from Tamariudus indica and Cassia fistula seeds were che...Most seed gums have been widely used in oral and topical pharmaceutical formulations, cosmetics, and food products because of their hydrophilic properties. Gums from Tamariudus indica and Cassia fistula seeds were chemically modified by carboxymethylation to improve their functionalities. The objective of the present study was to characterize and evaluate crude and carboxymethylated gums from T. indica and C. fistula seeds to achieve the controlled-release of diclofenac sodium(DS) in matrix tablet form. Both crude and carboxymethylated gums were characterized by Fourier transform infrared spectroscopy, Xray diffraction, and scanning electron microscopy. The results revealed that the gums were successfully modified by carboxymethylation and that the modified gums were amorphous in structure and had better flow properties. The carboxymethylated gums from both plant seeds did not exhibit cytotoxicity at concentrations lower than 0.5 mg/ml. All gum samples used as polymeric controlled-release agents were formulated into DS matrix tablets. Hardness and thickness tests were conducted as in-process tests. Drug content estimation and in vitro drug release studies were carried out to evaluate the matrix tablets. Increasing the concentration of gums increased compression time and hardness while it reduced the thickness. Furthermore, the results fitted well with the Korsmeyer–Peppas model. Moreover, the DS tablets were found to release the drug by super case II transport(relaxation). In summary, the carboxymethylated gum from T. indica and C. fistula seeds is an excellent, naturally sourced gum with high physicochemical and functional qualities, and can potentially be used in pharmaceutical applications as a disintegrant, diluent, and drug release-controlling agent.展开更多
A new chitosan-supported borohydride reducing reagent (CBER) was prepared by treatment of KBH4 with the resin of chitosan derivative, which was first synthesized from: the reaction of cross-linked chitosan microsphere...A new chitosan-supported borohydride reducing reagent (CBER) was prepared by treatment of KBH4 with the resin of chitosan derivative, which was first synthesized from: the reaction of cross-linked chitosan microsphere with glycidyl trimethylammonium chloride. CBER could reduce aromatic carbonyl compound to corresponding alcohol.展开更多
目的探讨硫化铜(CuS)/氧化石墨烯(GO)/壳聚糖(CS)/纳米羟基磷灰石(nHA)复合材料(CGCHs)的抗菌和促成骨作用及其作用机制。方法采用水热法合成CuS/GO纳米颗粒,通过原位沉淀法合成CS/nHA支架和CGCHs支架,检测材料表征、光热转换性能和生...目的探讨硫化铜(CuS)/氧化石墨烯(GO)/壳聚糖(CS)/纳米羟基磷灰石(nHA)复合材料(CGCHs)的抗菌和促成骨作用及其作用机制。方法采用水热法合成CuS/GO纳米颗粒,通过原位沉淀法合成CS/nHA支架和CGCHs支架,检测材料表征、光热转换性能和生物安全性,评估CGCHs组和近红外光(NIR)照射下CGCHs(CGCHs+NIR)组的细菌抑制效果及其对细菌生物膜相关基因表达的影响,观察CGCHs和CS/nHA不同材料组的促成骨分化和成骨、破骨相关基因表达。结果CGCHs是具有高度孔隙率的三维支架,在CuS/GO浓度为200μg/mL时CGCHs同时兼具良好的红外升温效果和生物安全性。琼脂糖平板涂菌和细菌死活染色结果均表明CGCHs+NIR组抗菌性能最佳,生物膜相关基因qPCR检测证实其具有抑制细菌生物膜相关基因表达的作用。茜素红染色结果表明CGCHs具有良好的体外促成骨性能,体外共培养3、7、14、21和28 d qPCR结果表明CGCHs对成骨早期和晚期相关基因表达均具有促进作用。与破骨细胞共培养结果可观察到CGCHs具有抑制破骨细胞形成的作用,细胞凋亡检测结果进一步验证这一结论,破骨分化相关基因qPCR检测结果表明,CGCHs主要通过抑制抗酒石酸酸性磷酸酶、组织蛋白酶K、CTR、P65和P38在共培养7、14 d的表达来抑制破骨细胞的分化。结论作为纳米复合材料,CGCHs生物安全性好,具有良好的红外光热协同抗菌作用,在促成骨分化的同时抑制破骨细胞分化,有望为感染性骨缺损治疗提供新的思路。展开更多
This paper reports a new method to prepare chitosan membrane which could be used as a biomedical material. Addition of a fixation agent composed of alcohol, glycerol and potassium hydroxide can accelerate the sol-gel ...This paper reports a new method to prepare chitosan membrane which could be used as a biomedical material. Addition of a fixation agent composed of alcohol, glycerol and potassium hydroxide can accelerate the sol-gel transformation process and hence shorten the preparation period. The present method takes about 6 h to get a flexible membrane with fine appearance, The physical and biological properties of the membrane were also investigated and compared with the membrane prepared by conventional method.展开更多
文摘The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole （Ag-CMCTS-TBZ） prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.
基金the Higher Education Research Promotion-National Research Universities(HERP-NRU)for financial support under grant no.2559A10862013
文摘Most seed gums have been widely used in oral and topical pharmaceutical formulations, cosmetics, and food products because of their hydrophilic properties. Gums from Tamariudus indica and Cassia fistula seeds were chemically modified by carboxymethylation to improve their functionalities. The objective of the present study was to characterize and evaluate crude and carboxymethylated gums from T. indica and C. fistula seeds to achieve the controlled-release of diclofenac sodium(DS) in matrix tablet form. Both crude and carboxymethylated gums were characterized by Fourier transform infrared spectroscopy, Xray diffraction, and scanning electron microscopy. The results revealed that the gums were successfully modified by carboxymethylation and that the modified gums were amorphous in structure and had better flow properties. The carboxymethylated gums from both plant seeds did not exhibit cytotoxicity at concentrations lower than 0.5 mg/ml. All gum samples used as polymeric controlled-release agents were formulated into DS matrix tablets. Hardness and thickness tests were conducted as in-process tests. Drug content estimation and in vitro drug release studies were carried out to evaluate the matrix tablets. Increasing the concentration of gums increased compression time and hardness while it reduced the thickness. Furthermore, the results fitted well with the Korsmeyer–Peppas model. Moreover, the DS tablets were found to release the drug by super case II transport(relaxation). In summary, the carboxymethylated gum from T. indica and C. fistula seeds is an excellent, naturally sourced gum with high physicochemical and functional qualities, and can potentially be used in pharmaceutical applications as a disintegrant, diluent, and drug release-controlling agent.
基金the National Natural Science Foundation of China (No.29977014).
文摘A new chitosan-supported borohydride reducing reagent (CBER) was prepared by treatment of KBH4 with the resin of chitosan derivative, which was first synthesized from: the reaction of cross-linked chitosan microsphere with glycidyl trimethylammonium chloride. CBER could reduce aromatic carbonyl compound to corresponding alcohol.
文摘目的探讨硫化铜(CuS)/氧化石墨烯(GO)/壳聚糖(CS)/纳米羟基磷灰石(nHA)复合材料(CGCHs)的抗菌和促成骨作用及其作用机制。方法采用水热法合成CuS/GO纳米颗粒,通过原位沉淀法合成CS/nHA支架和CGCHs支架,检测材料表征、光热转换性能和生物安全性,评估CGCHs组和近红外光(NIR)照射下CGCHs(CGCHs+NIR)组的细菌抑制效果及其对细菌生物膜相关基因表达的影响,观察CGCHs和CS/nHA不同材料组的促成骨分化和成骨、破骨相关基因表达。结果CGCHs是具有高度孔隙率的三维支架,在CuS/GO浓度为200μg/mL时CGCHs同时兼具良好的红外升温效果和生物安全性。琼脂糖平板涂菌和细菌死活染色结果均表明CGCHs+NIR组抗菌性能最佳,生物膜相关基因qPCR检测证实其具有抑制细菌生物膜相关基因表达的作用。茜素红染色结果表明CGCHs具有良好的体外促成骨性能,体外共培养3、7、14、21和28 d qPCR结果表明CGCHs对成骨早期和晚期相关基因表达均具有促进作用。与破骨细胞共培养结果可观察到CGCHs具有抑制破骨细胞形成的作用,细胞凋亡检测结果进一步验证这一结论,破骨分化相关基因qPCR检测结果表明,CGCHs主要通过抑制抗酒石酸酸性磷酸酶、组织蛋白酶K、CTR、P65和P38在共培养7、14 d的表达来抑制破骨细胞的分化。结论作为纳米复合材料,CGCHs生物安全性好,具有良好的红外光热协同抗菌作用,在促成骨分化的同时抑制破骨细胞分化,有望为感染性骨缺损治疗提供新的思路。
基金Project supported by the Natural Science Foundation of Zhejiang Province (No. 500041)
文摘This paper reports a new method to prepare chitosan membrane which could be used as a biomedical material. Addition of a fixation agent composed of alcohol, glycerol and potassium hydroxide can accelerate the sol-gel transformation process and hence shorten the preparation period. The present method takes about 6 h to get a flexible membrane with fine appearance, The physical and biological properties of the membrane were also investigated and compared with the membrane prepared by conventional method.
