流动注射化学发光法测定头孢类β-内酰胺抗生素

Determination of Ceph - Based p - Lactam Antibiotics by Flow - Injection Analysis with Chemiluminescence Detection

目的:确定以Ce(Ⅳ)直接氧化化学发光法分析测定头抱类β-内酰胺抗生素的新方法。方法:由于β-内酰胺抗生素水解一般都生成含有巯基(-SH)的化合物,用Ce(Ⅳ)直接氧化含巯基(-SH)的化合物能产生弱发光,且Rh6G能大大增强此弱发光,由此建立了测定头孢拉定等5种头抱类β-内酰胺类抗生素的FIA-CL分析法。结果:在选定的最佳条件下,经测试5个头孢类抗生素浓度在1.0×10^(-8)～1.5×10^(-5)g·mL^(-1)范围内与化学发光强度呈良好的线性关系。对5.0×10^(-6)g·mL^(-1)的头孢试样进行11次平行测定,得到RSD对头孢拉定、头孢呋辛钠、头孢噻肟钠、头孢曲松钠、头孢哌酮钠分别为2.2％,2.5％,2.7％,2.8％,2.8％。其检出限(3σ)对5个头孢类抗生素顺次分别为3.0×10^(-8),3.5×10^(-8),3.8×10^(-8),3.9×10^(-8),4.0×10^(-8),4.0×10^(-8)g·mL^(-1)。结论:本方法快捷、简便且具有较高的灵敏度,本法用于头孢合成样品的分析,结果满意。

Objective: Establish new method of determination of ceph - based β - lactam antibiotics in Ce ( IV ) oxidation chemiluminescence system. Method: Apart from hydrolysis in very strong basic condition, hydrolysis of β -lactam antibiotics produced mercapto - containing compounds in acidic, basic, and neutral condition. It was found that mixing of Ce ( IV ) and mercapto - containing compound in the acidic condition produced weak chemiluminescence greatly sensitized by Rh6G. Based on the above discovery, a FIA - CL method was developed for determination of the following five ceph - based β - lactam antibiotics, namely, cefradine, cefuroxime sodium, cefotaxime sodium, ceftriaxone sodium, cefoperazone sodium. Results: In the optimum conditions, CL intensities were proportional to concentrations of the studied drugs in the range 1. 0 × 10-8- 1. 5 × 10- 5 g·mL-1. For the five ceph - based β - lactam antibiotics, relative standard deviations ( RSD) are 2.2% , 2. 5% , 2.7% , 2.8%, 2.8% (n = 11), respectively. The limits of detection are 3. 0 × 10-8, 3. 5×10-8, 3. 8×10-8, 3.9 ×10-8, 4.0×10-8, 4.0 ×10-8 g · mL-1 respectively. Conclusion: The method is easy and rapid, with very sensitive. The method has been applied to the determination of studied drugs in synthetical samples with satisfactory results.