辐射聚合FT-207的体内释放研究

对室温下辐射聚合制备的药物缓释系统进行了体内研究,家兔背部皮下埋植ＦＴ－２０７聚合体,用ＨＰＬＣ测定,结果显示ＦＴ－２０７聚合物埋植组１周后血清药物浓度为１μｇ／ｍＬ,其聚合体周围组织药物浓度达７６±１０．４μｇ／ｍＬ,而无卫器官较低,与口服、静脉、腹腔给药等常规方式要比,证实采用常规给药方法血清药物２较高且持续时间短,包埋缓释药物血清浓度较低、持续时间较长。     

辐射制备缓释抗癌药阿糖胞苷的研究

报告了甲基丙烯酸酯类在室温下进行辐射聚合制备缓释抗癌药阿糖胞苷（Ａｒａ－Ｃ）的研究结果。结果表明，不仅亲水性单体，而且疏水性单体（包括ＭＭＡ、ＥＭＡ和ＢＭＡ等）都可用于辐射固化。加入到亲水性基质中的疏水性单体可以延缓药物的离体释放，其顺序是ＭＭＡ＜ＥＭＡ＜ＢＭＡ，央ＭＭＡ－ＨＥＭＡ共聚物中，Ａｒａ－Ｃ释放率随着基质中的ＭＭＡ含量增加而降低。药物的离体释放还受许多困素的控制，结果显示：药物释放量随着     

Drug release assays from new chitosan/pHEMA membranes obtained by gamma irradiation

With the purpose of obtaining a biocompatible and microbiologically safe matrix that simultaneously could be used as wound dressing material and as a controlled drug release system, membranes with different thickness and different contents in chitosan and hydroxyethyl methacrylate (HEMA) have been prepared by γ irradiation from a ⁶⁰Co source. Antibiotic release experiments were performed before or after irradiation over amoxicillin loaded chitosan/pHEMA membranes in physiological saline solution, and monitored by UV-Vis spectrometry.Results point out a fast amoxicillin release with similar release profile in all studied membranes. The amount of released drug was shown to be dependent on membranes network crosslinking due composition, radiation and membrane thickness.     

辐射制备热敏性水凝胶及控制释放

通过在空气中预辐射聚丙烯，将单体Ｎ－异丙基丙烯酰胺接枝到聚丙烯多孔膜的表面上，得到一种新型的具有良好的热敏性及机械性能的水凝胶。研究了各种因素对接枝后应的影响，考察了其热敏性能及表面形貌，通过变温度可改变多孔膜孔膜大小，并产针其用于托马斯亮蓝分子的渗透及控释过程。     

Smoke release behaviour of burning pools of liquid sodium

The analysis of the reactor safety and environmental protection for sodium cooled fast reactors requires an indepth knowledge of the smoke release behaviour of liquid sodium spillages in accidental conditions. The present study is aimed at experimental determinations of specific smoke release rates resulting from burning of sodium pools in closed as well as in open atmosphere.The pool temperature is controlled by incorporating an integrated cooling and heating facility in the burn-pot. Controlled test atmosphere is effected by regulating the oxygen and moisture content of the combustion chamber. In isothermal conditions (temperature of the pool 600±50°C) oxygen concentrations have a pronounced effect on the smoke release rate which diminishes as oxygen concentration increases. On the other hand, increasing oxygen content results in a slow fall of smoke release rate in non-isothermal conditions until at an oxygen concentration of about 7% (v/v) when there is a modest rise. In open atmosphere the smoke release rates show a rising trend in logarithmic scale with increasing pool area.     

Development of novel hydrogels by modification of sterculia gum through radiation cross-linking polymerization for use in drug delivery

In order to modify the sterculia gum polysaccharide, to develop the hydrogels meant for the drug delivery, we have prepared sterculia gum, 2-hydroxyethylmethacrylate (HEMA) and acrylic acid (AAc) based hydrogels by radiation-induced crosslinking polymerization. Polymeric networks (hydrogels) thus formed were characterized with SEMs, FTIR,TGA and swelling studies which were carried out as a function monomers concentration, radiation dose, amount of sterculia contents in the polymer matrix and nature of the swelling medium. This paper discusses the swelling kinetics of the hydrogels and release dynamics of anti-diarrhea model drug ornidazole from the hydrogels to evaluation of swelling and drug release mechanism. Diffusion exponent ‘n’ have 0.73, 0.56 and 0.61 values and gel characteristic constant ‘k’ have 1.28 × 10⁻², 2.95 × 10⁻² and 2.14 × 10⁻² values in distilled water, pH 2.2 buffer and pH 7.4 buffer. The release of drug from the polymer matrix occurred through non-Fickian diffusion mechanism. The values for the late time diffusion coefficients have been lower than the values of initial and average diffusion coefficients. It reflects that in the initial stages rate of release of drug from polymer matrix was higher as compared to the late stages, it means after certain time the drug release occurred in controlled manner.     

一种水凝胶药物缓释膜的制备及其性能研究

研制一种能加速伤口愈合的水凝胶药物缓释膜。应用冷冻-解冻法制备了含（或不含）药物的水凝胶膜,研究其理化性能及药物体外释放规律;应用扩散法研究了冷冻-解冻过程对庆大霉素效价的影响。结果显示,冷冻4h形成的水凝胶溶胀度为841．21％,凝胶分数、抗张强度和断裂伸长率分别为96．10％、0．222 MPa和673．50％;冷冻4h的冻融过程对硫酸庆大霉素的效价无影响（p〉0．05）;掺加药物的水凝胶膜在6h内药物陕速释放达高峰,累计释放率为59．57％,而后缓慢释放,持续到第5天,其释放规律符合Higuchi方程,释药原理属骨架型扩散释放机制。结果表昵,该法制备的水凝胶膜具有良好的理化眭能和抗生素缓释功能。     

In vitro release studies of vitamin B12 from poly N-vinyl pyrrolidone/starch hydrogels grafted with acrylic acid synthesized by gamma radiation

Co-polymeric hydrogels containing N-vinyl pyrrolidone and starch grafted with acrylic acid were synthesized by gamma radiation to be used as drug delivery system. Their gel contents, grafting swelling and thermal gravimetric analysis were evaluated. The gel content increases by increasing the irradiation dose up to 50 kGy, then decreases. The grafting percent increases by the increasing of acrylic acid. The thermal stability and the rate of the thermal decomposition changed according to the different compositions. The maximum rate of the thermal decomposition decreases by increasing the irradiation dose from 20 to 30 kGy and increases by increasing the irradiation dose from 30 to 70 kGy. The hydrogels loaded with vitamin B₁₂ demonstrated a decrease release in acidic medium than the neutral one.     

PIXE investigation of in vitro release of chloramphenicol across polyvinyl alcohol/acrylamide hydrogel

Hydrogels based on polyvinyl alcohol and different amounts of acrylamide monomer were prepared by thermal cross-linking in the solid state. The hydrogels were investigated for drug delivery system applications. Chloramphenicol was adopted as a model drug to study its release behavior. Particle induced X-ray emission was utilized to study the drug release behavior across the hydrogels and a comparison study with ultraviolet measurements was performed. Fourier Transform Infrared measurements were carried out for molecular characterization. The releasing behavior of the drug exhibits a decrease and a subsequent increase in the release rate, as the acrylamide monomer increases. Characterization of the hydrogels has shown a competitive behavior between crosslinking with AAm acrylamide monomer or oligomerized version, depending on the amount added to prepare the hydrogels.     

二次自蔓延高温合成钙钛矿固化90Sr

采用二次自蔓延高温合成(SHS)技术制备钙钛矿固化高放废物90Sr,通过XRD, SEM和PCT粉末浸泡法,研究了钙钛矿固化体的微观组织、浸出率以及其对高放废物~(90)Sr的最大包容量.结果表明,固化体样品密度高、孔隙率小,浸出率都小于0.1 g/(m~2·d),对SrO的包容量可达36%(质量分数);表明自蔓延高温合成的钙钛矿人造岩石固化体化学稳定性好、包容量大,是固化高放废物的理想固化体.