Simultaneous determination of abamectin homologs H 2 B 1a and H 2 B 1b in gel formulation by high performance liquid chromatography

ABSTRACT Abamectin is a drug with antiparasitic properties used in several pharmaceutical formulations. The objective of this research was to develop and validate a high performance liquid chromatographic (HPLC) method for quantification of the two abamectin homologs (H2B1a and H2B1b) in gel formulation. This HPLC method was validated using a LichroCart(r) 100 RP-18 (125 x 4 mm, 5 µm) column. The mobile phase contained of acetonitrile and water (95:5 v/v) with 1% acetic acid. The flow rate was 1.0 mL min-1 and UV detection was performed at 245 nm. Mobile phase solutions were prepared containing a nominal concentration 185.2 µg mL-1 H2B1a and 9.6 µg mL-1 H2B1b. The method displayed good linearity in the concentration range of 148.1 - 222.3 µg mL-1 and 7.7 - 11.5 µg mL-1, for H2B1a and H2B1b, respectively, with a correlation coefficient of (r)> 0.99 for both compounds, calculated by the least mean squares method. Detection limits (DLs) were 2.8 µg mL-1 and 1.2 µg mL-1 and quantitation limits (QLs) were 8.6 µg mL-1 and 3.8 µg mL-1, for H2B1a and H2B1b, respectively. The method is simple, economical and efficient for the quantitative determination of abamectin H2B1a and H2B1b homologs in pharmaceutical preparations.摘要 阿维菌素（Abamectin）是一种具备抗寄生虫特性的药物，已应用于多款药物制剂中。本研究旨在开发并验证一种高效液相色谱（High Performance Liquid Chromatography，HPLC）法，用于定量测定凝胶制剂中的两种阿维菌素同系物（H2B1a和H2B1b）。该HPLC方法采用LichroCart® 100 RP-18（125 × 4 mm，5 µm）色谱柱完成方法学验证。流动相为含1%乙酸的乙腈-水混合溶液，体积比为95:5。流速设定为1.0 mL·min⁻¹，紫外检测波长为245 nm。配制的标准溶液中，H2B1a的标称浓度为185.2 µg·mL⁻¹，H2B1b为9.6 µg·mL⁻¹。结果显示，H2B1a在148.1~222.3 µg·mL⁻¹、H2B1b在7.7~11.5 µg·mL⁻¹的浓度范围内均呈现良好线性关系，两种化合物的相关系数（r）均大于0.99，相关系数通过最小二乘法计算得到。H2B1a和H2B1b的检测限分别为2.8 µg·mL⁻¹和1.2 µg·mL⁻¹，定量限分别为8.6 µg·mL⁻¹和3.8 µg·mL⁻¹。本方法简便、经济且高效，可用于药物制剂中阿维菌素H2B1a与H2B1b同系物的定量测定。