高浓度青霉素含量的旋光法测定及影响因素分析

Optical Rotation Method for the Determination of the Content of the High Concentration of Penicillin and Influence Factors Analysis

摘要: 青霉素钠是一种临床常用的抗生素，其干燥粉末性状稳定，但配置成水溶液后性状极不稳定，易被酸、碱、醇、氧化剂、金属离子分解破坏，某种情况下其旋光度也将发生相应的变化，因此临床上为保证药效要求青霉素溶液需现用现配，必要时应及时检测浓度的变化[1]。有关青霉素含量的测定方法有很多，其中包括碘量法、固定pH滴定法、分光光度法、HPLC法、旋光法等。由于青霉素溶液的旋光度和浓度在一定范围内具有线性关系的特点，以往曾有文献报道，通常仅对1.0 mg/ml~10.0 mg/ml的低浓度青霉素溶液适用旋光法测定。本文依据旋光法对较高浓度青霉素的含量进行测定，同时对实验的有关影响因素进行研究和分析。实验结果表明，青霉素溶液在10.0 mg/ml~30.0 mg/ml的高浓度范围内也呈良好的线性关系，其线性方程为y = 0. 2903x + 0.1712，相关系数r = 0.9993。对比药典中采用的碘量分析法，旋光法具有操作简便快速、结果准确可靠、节省实验材料等优点，并且在一定程度上可以消除其他因素的影响，具有较高的应用价值，非常适合于一般医药院所的快速检测。 Penicillin sodium is a commonly used clinical antibiotic. It is noted that the dry powder is stable, but in water solution it is very unstable. It is easily decomposed and destructed by acid, alkali, alcohol, oxidative agent, metal ion. Thus, to ensure the efficiency of penicillin solution, it is clinically required to prepare it just before use. In some cases, it is necessary to timely detect the concentration changing. There are many methods to check the content of the penicillin solution, such as, the iodometric method, pH fixed titration, spectrophotometric method, HPLC method, and optical method. In the literature a linear relationship between optical rotation and concentration at lower concentration of 1.0 mg/ml - 10.0mg/ml has previously been reported. In this paper, we investigated content determination of penicillin at higher concentrations based on polarimetric method, and studied the role of the influencing factors. The experimental results showed that penicillin solution at 10.0 mg/ml - 30.0 mg/ml high concentration also show a good linear relationship, the linear equation is y = 0.2903x + 0.1712, the correlation coefficient r = 0.9993. In contrast with the Pharmacopoeia of iodine quantity method, optical method is simpler, more rapid, more accurate, more reliable, and it can save experimental materials. Moreover, to a certain extent, it can eliminate the influence of other factors. It is a very suitable method for general medical institutes to rapidly detect the content of penicillin solution.