Greenness, blueness, and whiteness profiles of HPTLC method for the simultaneous assay of tenofovir and emtricitabine in fixed-dose combination dosage forms

The literature does not have any sustainable high-performance thin-layer chromatographic (HPTLC) methods for concurrently identifying tenofovir (TEN) and emtricitabine (ECT). Therefore, the proposed study develops and verifies a sustainable reverse-phase HPTLC methodology for determining TEN and ECT concurrently in their fixed-dose combination (FDC) products. The wavelength at which TEN and ECT were simultaneously identified was 255 nm. A 70:30 v/v binary mixture of ethanol and water served as the green development system. The method was validated for accuracy, precision, robustness, sensitivity, and specificity according to ICH guidelines. The validated method was applied for the simultaneous determination of TEN and ECT in commercial FDC tablets. The method's greenness, blueness, and whiteness profiles were evaluated using eight different tools: "the analytical eco-scale (AES), chloroform toxicity (ChlorTox), analytical GREEnness (AGREE), modified green analytical procedure index (MoGAPI), complex MoGAPI, blue applicability grade index (BAGI), carbon footprint reduction index (CaFRI), and click analytical chemistry index (CACI)". For both medications, the devised technique was linear in the range of 25-1000 ng/band. In addition, the created approach was proven to be accurate (% recoveries = 99.12-100.70 for TEN and 100.57-101.83 for ECT), precise (% RSD = 0.85-0.99 for TEN and 0.88-0.97 for ECT), sensitive (LOD = 8.50 ng/band for TEN and 8.39 ng/band for ECT, LOQ = 25.51 ng/band for TEN and 25.19 ng/band for ECT), and robust (% RSD = 0.82-0.86 for TEN and 0.94-0.99 for ECT). Using the current method, the amount of TEN in commercial FDC tablet brands A and B was 98.58 ± 1.21% and 101.13 ± 1.30%, respectively. The amount of ECT in FDC brands A and B was 99.82 ± 1.29 and 100.64 ± 1.37%, respectively. The findings of all the greenness, blueness, and whitening tools, such as AES (93), ChlorTox (0.72 g), AGREE (0.77), MoGAPI (85), complex MoGAPI (90), BAGI (85), CaFRI (89), and CACI (87), demonstrated that the current method had the notably sustainable profiles. The greenness parameters of present method were better than reported HPTLC approaches. The findings of the study suggested that the recommended method may be applied to precisely evaluate TEN and ECT in commercial formulations.