论文部分内容阅读
目的:建立提取大鼠血浆中总PEG的方法,并研究PEG-Dipeptide-TNF-α结合物的在大鼠体内药代动力学。方法:采用125I同位素标记PEG-Dipeptide-TNF-α,利用有机溶剂氯仿萃取血浆中总PEG量,两相体系分光光度法进行验证,放射免疫γ计数器检测萃取物放射性计数,并用3P87药动学软件进行曲线拟合并计算参数。结果:血浆样品冷冻干燥后用氯仿提取,两相体系分光光度法检测结果为高、中、低3个浓度样品的相对回收率在100%附近,日内精密度RSD均小于3%,空白血浆中的内源性物质不干扰已知放射数的样品。3P87药动学软件计算的结果显示,TNF-α和PEG-Dipeptide-TNF-α半衰期(t1/2)分别为0.31和21.22h,表明新型的PEG修饰技术可以延长的TNF-α半衰期。结论:本方法建立了血浆中总PEG的提取方法,专属性高,分离完全,操作简单,成本低廉,符合生物等效性指导原则关于生物样品分析方法的基本要求。
Objective: To establish a method for extracting total PEG from rat plasma and to study the pharmacokinetics of PEG-Dipeptide-TNF-α conjugate in rats. Methods: PEG-Dipeptide-TNF-α was labeled with 125I isotope and the total amount of PEG in plasma was extracted with chloroform as organic solvent. The two-phase spectrophotometry was used to verify the radioactivity. Radioimmunoassay was used to detect the radioactivity of extracts. Curve fit and calculate parameters. Results: The plasma samples were extracted with chloroform after freeze-drying. The two-phase spectrophotometry showed high, medium and low relative recoveries of 100%, and the intra-day precision RSD was less than 3% The endogenous substances do not interfere with the known emission number of samples. The results of 3P87 pharmacokinetic software showed that the half-lives of TNF-α and PEG-Dipeptide-TNF-α were 0.31 and 21.22 h, respectively, indicating that the novel PEG modification can prolong the half-life of TNF-α. Conclusion: This method established a method for the extraction of total PEG in plasma. It has the characteristics of high specificity, complete separation, simple operation and low cost. It meets the basic requirements of bioequivalence guidelines for biological sample analysis.