A cost-effective and sensitive TLC-densitometric identification of meloxicam

The influence of different chromatographic conditions and the process of spot visualization on determining the limit of detection as well as quantification (LOD and LOQ) of meloxicam by TLC-densitometric technique was estimated. Of all chromatographic conditions tested, the lowest limiting values, thus the best sensitivity, in the NP-TLC system was achieved on silica gel 60F₂₅₄ and neutral aluminum oxide plates developed with the mobile phase consisting of ethyl acetate/toluene/n-butylamine (2:2:1, V/V/V). In the case of the RP-TLC method, a mixture of methanol/water (8:2, V/V) enabled densitometric detection of meloxicam at the lowest concentration level on RP-8F₂₅₄ and RP-18F₂₅₄ plates. Additionally, the smallest LOD value of meloxicam ensured crystalline violet and gentian violet as visualization agents on silica gel 60F₂₅₄ and neutral aluminum oxide 150F₂₅₄ plates, resp. Comparison of the densitometrically obtained spectra of meloxicam drug and its standard after the use of appropriate visualization agents could be a good and cheap alternative tool for the identification of meloxicam as an active pharmaceutical ingredient.