HPLC法测定琥乙红霉素中游离红霉素的含量

目的: 建立高效液相色谱法测定琥乙红霉素及片剂中游离红霉素,并按所建方法对全国33家企业的251批琥乙红霉素片中的游离红霉素进行测定.方法: 采用SPOLAR C₁₈(250 mm×4.6 mm,5 μm)色谱柱,流动相A为磷酸二氢钾溶液(称取磷酸二氢钾3.4 g,加水适量溶解,加三乙胺2.75 mL,再以水稀释至1000 mL,用盐酸调节pH至3.0),流动相B为乙腈,线性梯度洗脱,流速为1.0 mL·min ^-1,柱温为30 ℃,检测波长为205 nm.结果: 片剂辅料无干扰,线性范围为0.06~1.2 mg·mL^-1,r=0.9999;检测限为0.024 μg,定量限为0.12 μg;平均加样回收率(n=9)为100.2%,RSD为1.3%.251批样品测定游离红霉素含量在5%以内的占65.3%;在5%~10%之间的占27.1%;大于10%的占8.0%.结论: 本文建立的方法分离效果好,灵敏度高,可用于琥乙红霉素及片剂中游离红霉素的测定.有必要尽快建立HPLC方法更加准确测定琥乙红霉素及片剂中游离红霉素的含量.

Objective: To improve the controllability of quality standard as well as the sensitivity and precision of test method, to study and establish the HPLC method to determine free erythromycin in erythromycin ethylsuccinate and tablets, and determine free erythromycin in 251 batches of erythromycin ethylsuccinate tablets from 33 enterprises across the country. Methods: The column was SPOLAR C₁₈(250 mm×4.6 mm, 5 μm)with the mobile phase A[phosphate buffer solution(0.02 mol·L^-1 potassium dihydrogen phosphate solution including 2.75 mL·L^-1triethylamine, pH adjusted to 3.0 by hydrochloric acid)], and the mobile phase B(acetonitrile)under linear gradient elution.The flow rate was 1.0 mL·min^-1, the column temperature was 30 ℃, the detection wavelength was 205 nm. Results: Tablet excipients had no interference, with the linear range of 0.06-1.2 mg·mL^-1(r=0.9999);the detection limit was 0.024 μg, the limit of quantification was 0.12 μg;the average recovery rate(n=9)was 100.2%, RSD was 1.3%.Samples with the content of free erythromycin below 5% accounted for 65.3% of the 251 batches of samples, samples with the content from 5% to 10% accounting for 27.1%, and those with the content more than 10% accounting for 8.0%. Conclusion: The method was proved to be sensitive and with good resolution, which can be used to determine free erythromycin in erythromycin ethylsuccinate and tablet preparations.It is necessary to establish the HPLC method to control the content of free erythromycin in erythromycin ethylsuccinate and tablet preparations as soon as possible.