Integrating micellar HPLC and green analytical chemistry tools in greenness assessment of five commonly Co-formulated antidiabetic drugs

Abstract

The ecological impact of routine quality control activities in the pharmaceutical industry is crucial, producing large amounts of dangerous organic waste. For that, the use of mixed-micellar LC was found beneficial. When sodium dodecyl sulfate (SDS) is mixed with Brij-35 as surfactants in the mobile phase, no organic modifier was needed for enhancing the analytes' elution time or resolution. In the proposed study, five antidiabetic drugs belonging to different antidiabetic classes; namely metformin (MTF), glibenclamide (GBC), gliclazide (GCZ), linagliptin (LNT) and dapagliflozin (DPF), have been studied using organic-solvent free Micellar RP-HPLC technique. The combination of double or even triple antidiabetic therapies from different classes is common and was proved efficient for the control of type-2 diabetes. The optimal mobile phase was composed of 0.12 M SDS, 0.008 M Brij-35 and 0.15 M triethylamine in water, adjusted to pH 4.5. The flow rate was set at 1.5 mL min−1 on RP-monolithic column (100 × 4.6 mm). Photodiode array detection was set at wavelength 245 nm for MTF and 225 nm the other analytes. Linearity ranges were 50–600 μg mL−1 for MTF, and 5–60, 2.5–30, 7.5–60, and 2.5–30 μg mL−1 for DPF, LNT, GCZ and GBC, respectively (R2 ≥ 0.997). Trueness and precision have been established across the specified ranges with recovery percentages range 98–105% and relative standard deviation of the results less than 2.5%. The obtained results of resolution, peaks’ symmetry and theoretical plates for the drugs under study proved the analytical capability of using mixed-micellar mobile phases for elimination of the organic-solvents without affecting the separation efficiency.