茶碱与氧氟沙星合用时血药浓度的紫外测定方法

A dual-wavelength spectrophotometry of serum theophylline with concomitant use of ofloxacin

目的 建立一种能消除氧氟沙星干扰的茶碱血药浓度测定方法。方法 用硫酸铵沉淀血清蛋白后以氯仿 正己烷 (7∶3)混和溶剂萃取 ,复用NaOH液 (0 .1mol·L-1)抽提 ,并选择氧氟沙星的等吸收点 2 75 ,2 99.5nm为茶碱的测定波长。结果 线性回收方程 :ΔA =6 .6 4× 10 -3 + 4.95 × 10 -3 C ,r =0 .9997,线性范围 :5 .0～ 40 .0mg·L-1。方法回收率 10 0 .3% ,RSD为 1.2 % ;萃取回收率 87.7% ,RSD为 4.6 %。结论 本法不受氧氟沙星等多种抗菌素共存的干扰 。

OBJECTIVE: To develop a method for the determination of theophylline in serum with concomitant use of ofloxacin. METHODS: Theophylline was serum was extracted with chloroform-hexane(7:3, v/v) after some ammonium sulfate was added. It was re-extracted with NaOH solution (0.1 mol&middotL-1) and detected with a UV spectrophotometer at 275 nm and 299.5 nm respeitively. RESULTS: The method was linear over the range of 5.0 ∼ 40.0 mg&middotL-1 (r = 0.9997, n = 7). The average recovery of methodology was 100.3 % (RSD = 1.2 %), and the extraction recovery from serum was 87.7 % (RSD = 4.6%). CONCLUSION: This practical method for the determination of serum theophylline can eliminate the interference of ofloxacin and other antibiotics.