Simultaneous high-performance thin-layer chromatography densitometric assay of trandolapril and verapamil in the combination preparation.
A high-performance thin-layer chromatography (TLC) method coupled with densitometric analysis has been developed for simultaneous measurement of trandolapril (TRA) and verapamil (VER) in 2-component mixtures and in their combination capsules. The active substances were extracted from capsules with methanol (mean recovery: 103.4% for TRA, 97.13% for VER) and chromatographed on TLC plates coated with silica gel 60 F254 in horizontal chambers with ethyl acetatc-ethanol-acetic acid (8 + 2 + 0.5, v/v) mobile phase. Chromatographic separation of these components was followed by ultraviolet densitometric quantification at 215 nm. The calibration graphs were constructed over the concentration range from 0.5 to 1.5 microg/microL (corresponding to 5.0-15.0 microg/spot) for both drugs with good correlation (r > or = 0.990). Detection and quantitation limits were found to be 1.25 and 3.75 microg/spot for TRA and 0.15 and 0.45 microg/spot for VER, respectively. The proposed method was used for determination of both drugs in TRA-VER capsules with satisfactory precision [0.97% < relative standard deviation (RSD) < 4.50% for TRA, 0.49% < RSD < 3.10% for VER] and accuracy [2.16% < relative error (RE) < 4.90% for TRA, 1.73% < RE < 5.68% for VER].
Kowalczuk
Dorota
D
Medical University of Lublin, Faculty of Pharmacy, Department of Medicinal Chemistry, 6 Chodzki Str, 20-093 Lublin, Poland. dorkow@vp.pl
D015982:Bias; D002138:Calibration; D002214:Capsules; D002855:Chromatography, Thin Layer / Q000379:methods*; D003720:Densitometry / Q000379:methods*; D004338:Drug Combinations; D007211:Indoles / Q000032:analysis*; D012015:Reference Standards; D012044:Regression Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014700:Verapamil / Q000032:analysis*
D002214:Capsules; D004338:Drug Combinations; D007211:Indoles; C052035:trandolapril; D014700:Verapamil