PLGA-PEG-PLGA温敏水凝胶的体外释药行为

通过试管倒置法考察曲克芦丁对温敏水凝胶温敏性的影响。选用相变温度为25℃的PLGA-PEG-PLGA为载体,曲克芦丁为模型药物,物理混合法制备凝胶浓度为20%(质量分数)含药凝胶,采用无膜溶出模型研究其在体外不同温度下(40℃和30℃)的释药行为。结果显示:曲克芦丁的加入对温敏水凝胶的温敏性影响不大;通过改变PLGAPEG-PLGA温敏水凝胶的温度可以改变其释药速度。因此可以得出结论:PLGA-PEGPLGA水凝胶可作为药物脉冲式释放的载体,通过控制温度可控制其对药物的释放。     

Chitosan-g-PAA Hydrogels for Colon-Specific Drug Delivery: Preparation, Swelling Behavior and in vitro Degradability

A series of cross-linked hydrogels for colon-specific drug delivery were synthesized by graft copolymerization of Chitosan and acrylic acid using N, N'-methylene-bis-(acrylamide) as a cross-linker. Their swelling behavior in different pH buffer solutions and colonic enzymatic degradability were studied. The obtained results show that these hydrogels have good pH sensitivity which can avoid drug release in stomach, and their swelling kinetics in stimulant intestinal environment follow second-order swelling k...     

羊毛角蛋白/羟甲基纤维素钠共混载药膜的制备及体外释药性能

制备羊毛角蛋白/羟甲基纤维素钠共混载药膜,并考察其体外释药性能。采用溶液共混浇铸成膜法,以奥硝唑为模型药物制备载药膜,模拟人体血液环境,通过原料配比、变性剂用量、药物用量、pH值单因素对比试验考察体外释药性能,结果表明：羊毛角蛋白/羟甲基纤维素钠质量比60 40、戊二醛用量0.1%、反应时间1小时、温度37℃条件下制备的共混载药膜,具有良好的药物缓释作用和pH值敏感性。载药膜致密均匀,扫描电镜显示成膜状态良好,贮存6个月,外观形态及释药性基本不变。     

A Novel Drug Delivery System for Osteosarcoma Chemotherapy

1Introduction Osteosarcoma,35%ofhumanprimarybonecan cers,ishighlymalignantandtendstotransferandgrow permeantly.Chemotherapyisaneffectiveandbasicthera pyforosteosarcoma,buttheside effectofantineoplasticdrugslimitstheconcentrationofthemwhichinfluences thecu…     

单链型L-苯丙氨酸衍生物凝胶因子及体外释放的研究

由L-苯丙氨酸甲酯盐酸盐、氯甲酸苄酯和十二烷酰氯合成了凝胶因子.考察凝胶tGS（凝胶-溶胶转变温度）与tSG（溶胶-凝胶转变温度）关系,对布洛芬在凝胶中的释放及NMP在凝胶中的阻凝效果进行了研究.实验结果表明,凝胶因子可以在甲苯、二甲苯、大豆油和橄榄油等含苯环的溶剂中形成热可逆的物理凝胶,在非极性溶剂中不溶解.tGS明显高于tSG,凝胶因子含量的升高使布洛芬在凝胶中的释放减慢.通过SEM对凝胶因子在凝胶中形成的网络结构进行研究,发现在凝胶中形成了三维网络结构.     

Synthesis and Characterization of a Novel pH-sensitive Complex for Drug Release

A novel pH-sensitive complex was prepared by using oxidized konjac glucomannan and 4-aminosalicylic acid (4-ASA) through glutaraldehyde as a cross-linking agent. The product was characterized by FTIR and 13C NMR spectra, and the thermogravimetric analysis was also studied. The drug release studies in vitro showed that the amount of 4-ASA released from the complex was about 4%, 56% and 17% after 12 h at pH 1.2, 6.8 and 7.4, respectively. The data demonstrate that the rate of the drug release of the complex c...     

Syntheses and Drug Delivery Property of Biodegradable Polyether-Anhydrides

Both polyanhydrides and polyethers are new types of biodegradblepolymers. They are of particular interest as materials for controlled drug release systems duo to their excellent surface erosion properties of polyanhydrides and excellent biocompatibility of polyethers. They have been widly used in biomaterials.A series of polyether anhydrides elastomer were firstly synthesed through introducing PEG into the polyanhydrides chains. Their degradation and drug release property were also studied. These materials may be used in applications where materials are needed with properties more close to those of natural skin.     

Syntheses and Drug Delivery Property of Biodegradable Polyether-Anhydrides

Both pofyanhydrides and polyethers are new types of biodegradble polymers. They are of particular interest as materials for controlled drug release systems duo to their excellent surface erosion properties of poly-anhydrides and excellent biocompatibility of polyethers. They have been widly used in biomaterials. A series of polyether anhydrides elastomer were firstly synthesed through introducing PEG into the pofyanhydrides chains. Their degradation and drug release property were also studied.These materials may be used in applications where materials are needed with properties more close to those of natural skin.     

尼索地平缓释微丸的制备及其体外释放度的考察

研制了尼索地平缓释微丸并进行体外释放度考察。通过正交试验确定最佳处方和工艺,并进行质量考察。确定了以乙基纤维素、羟丙甲纤维素为阻滞剂,聚乙二醇6000为增塑剂的最佳薄膜衣处方。尼索地平缓释微丸可缓慢释放12h以上。制备缓释微丸的工艺简单,易于控制和操作,且释放度标准符合规定。     

明胶-壳聚糖共混载药膜的体外释药特性

溶剂挥发法制备明胶-壳聚糖（GICS）共混膜,作为药物持续释放载体治疗眼穿通伤.氢化可的松琥珀酸钠（HSS）作为模型药物.制备明胶和壳聚糖组成比例（体积比）为1：3和1：4,载药量一样的GICS药膜.pH＝7.4的缓冲溶液中降解实验显示,随着明胶加入量增加,提高了膜的溶解性,降解加快.体外释药实验显示药物释放与时间平方根呈函数关系,药物呈缓慢释放,能维持10 d以上的有效药物浓度,初步兔眼实验显示,该膜组织相容性好,治疗眼穿通伤效果明显.     

Drug Release Characteristics of Hydroxyapatite Bone Cement

1Introduction Hydroxyapatitebonecement(HAC)isanewlyde velopedartificialbonematerialusedforbonedefects.Itisaself settingandnonceramicbonematerial,whichismadeofcalciumphosphatepowderanddilutedacidor isotonicsaline.HAChasaverypracticalcharacteristic:itcanbes…