A selective and simple salting-out-assisted thin-layer chromatographic methodology
was developed for the simultaneous determination of two oral hypoglycemic drugs,
dapagliflozin (DAPA) and metformin (MET) in their pure forms, tablets and spiked
human plasma samples. Silica gel 60 F254 plates were used in the separation of the
two drugs using a mobile phase consisting of 0.5 M (NH4)2SO4 and methanol
(3:7, v/v). The plates were scanned in the reflectance mode at λmax = 237 nm. The
obtained retardation factor (Rf) values for DAPA and MET were 0.77 ± 0.02 and 0.25
± 0.02, respectively. The thin-layer chromatography method was validated according
to International Conference on Harmonization guidelines. The peak areas were linearly
increased with the increases in concentrations of 45–1,000 and 50–1,500 ng/band
for DAPA and MET, respectively. Moreover, the method was applied to estimate the
molecular lipophilicity parameters of DAPA and MET via retention data. The
suggested method was efficiently utilized for the analysis of DAPA and MET in
pharmaceutical tablets and plasma samples with recoveries 98.4–100.4 and RSDs in
the ranges of 1.4–2.6 and 2.2–3.0% for DAPA and MET, respectively.