多步梯度高效液相色谱法测定口腔溃疡涂剂中3组分的含量

目的建立多步梯度高效液相色谱法测定口腔溃疡涂剂中甲硝唑、盐酸丁卡因和醋酸地塞米松的含量。方法采用Kromasil C18柱（4.6 mm×250 mm,5μm）,流动相为甲醇-乙腈-0.5%的三乙胺溶液（用冰醋酸调pH至5.0）三元梯度洗脱,流速0.9 ml·min^-1,柱温25℃,检测器为DAD检测器,检测波长为313 nm和241 nm。结果甲硝唑、盐酸丁卡因和醋酸地塞米松的线性范围分别为20.0～100.0 mg·L^-1（r=0.9995）、6.7～33.4 mg·L^-1（r=0.999 9）和10.0～50.0 mg·L^-1（r=0.999 7）;平均回收率（n=9）分别为99.4%（RSD=0.64%）、99.5%（RSD=0.57%）和99.5%（RSD=0.61%）。结论该方法简便、准确、重复性好,可作为口腔溃疡涂剂的质量控制标准。

Determination of three constituents in oral ulcer paste by multiple-gradient HPLC

Aim To establish a multiple-gradient HPLC method for determining metronidazole,tetracaine hydrochloride and dexametha-sone acetate in oral ulcer paste.Method A Kromasil C18 column(4.6 mm × 250 mm,5 μm) was used.The mobile phase was com-posed of methanol,acetonitrile,0.5% triethylamine solution(adjusted to pH 5.0 with glacial acetic acid) with gradient elution.The flow rate was 0.9 ml.min-1,with acolumn temperature at 25℃.The UV detection wavelength was 313 nm and 241 nm.Results The linear ranges of metronidazole,tetracaine hydrochloride and dexamethasone acetate were 20.0 ～ 100.0 mg.L-1(r = 0.9995),6.7 ～ 33.4mg.L-1(r = 0.999 9) and 10.0 ～ 50.0 mg.L-1(r = 0.999 7) respectively.The average recovery rates(n = 9) were 99.4%(RSD =0.64%),99.5%(RSD =0.57%) and 99.5%(RSD =0.61%),respectively.Conclusion The method is simple,accurate and reproducible,which can be used for the quality control of stomatic ulcer paste.