Abstract
TLC-densitometric method was developed for the identification and quantitative determination of selected fluoroquinolones. Silica gel TLC 60 F254 plates were used as the stationary phase. For the separation of examined compounds the suitability of the following four mobile phases with different dynamic viscosity was checked: (I) methanol:ammonia:ethyl acetate:acetonitrile 1:1:2:1 v/v/v/v (1.70 mPa · s), (II) dichloromethane:methanol:isopropanol:ammonia 4:4:5:2 v/v/v/v (2.08 mPa · s), (III) dichloromethane:ethanol:toluene:ammonia:n-butanol:water 6:6:2:1.8:3:0.3 v/v/v/v/v/v (2.27 mPa · s), (IV) 1,4- dioxane:ammonia:tetrahydrofuran 6:3:2 v/v/v (3.24 mPa · s). The calculated values of retardation factors RF, capacity factors k, selectivity factors α, resolution factors Rs, and also asymmetry factors As for the evaluation of separation conditions were used. The obtained results confirmed that dynamic viscosity of the mobile phases is essential and influences the retention parameters of the studied fluoroquinolone chemotherapeutics. The validation results for the mobile phase IV indicate its suitability for the identification and also quantitative analysis of selected drugs in pharmaceutical analysis.
Acknowledgements
The authors would like to dedicate this article to the memory of Professor Jan Krzek, our adviser, mentor and Head of Department of Inorganic and Analytical Chemistry.