【摘要】 用GC MS(负化学电离,NCI)建立一个高灵敏度、快速测定氯霉素的新方法。在GC MS上用NCI和选择离子模式进行测定,提高了测定的灵敏度和抗干扰能力。采用程序升温汽化大体积进样,进样量为100μL,是常规进样量的100倍,使得方法的检出限降低了2个数量级,达到了5pg g。采用基质固相分散替代固相萃取,大大简化了样品前处理步骤,提高了方法的准确度和精密度。加标浓度为0 01～10 0ng g时,回收率在95 88%～107 69%之间,变异系数小于5 92%。更多还原

【Abstract】 A new method based on GC/MS with negative chemical ion(NCI) for determination of chloramphenicol is studied. Higher sensibility and better tolerance of disturbance of matrix are achieved through negative chemical ion(NCI) and selection ion monitoring model. By optimizing of programmed-temperature vaporization(PTV) large-volume injection, the total injection volume reaches 100 μL which is 100 times of ordinary injection volume. Thus, the detection limit can reduce to 5 pg/g. As matrix solid-phase disperse(MSPD) can do extracting, filtering and cleaning in the same time, the sample preparation becomes very simple and efficient. Furthermore, higher recovery and lower relative standard deviation are obtained. The recovery range is 95.88%～107.69% with relative standard deviation below 5.92% when the fortified level is 0.01～10.0 ng/g.更多还原