Simultaneous determination of guaifenesin enantiomers and ambroxol HCl using 50-mm chiral column for a negligible environmental impact.
Chiral stationary phases are conveniently used for enantiomeric separation of drugs by liquid chromatography. Consumption of large volumes of hazardous solvents is considered as a common challenge for the sustainability of this technique. To this end, a columnar chromatography has been adopted using 50-mm-length stationary phases. The study comprised five Phenomenex Lux cellulose- and amylose-based columns for the separation of guaifenesin (GUA) enantiomers. In addition, an experimental design was used to optimize the gradient profile for the separation of racemic GUA and ambroxol HCl (AMB) binary mixture. The chromatographic method was achieved using Lux Cellulose-1 (50 × 4.6 mm) as a chiral stationary phase and ethanol/water as a mobile phase with linear gradient elution of 20% to 70% ethanol in 6 minutes at a flow rate of 1.0 mL min-1 and UV detection at 270 nm. Linearity ranges were found to be 50 to 1000 μg mL-1 and 15 to 450 μg mL-1 for each GUA enantiomer and AMB, respectively. Environmental, health and safety tool was used to assess and compare greenness of the proposed and reported methods. Short column indeed reduces the environmental impact by decreasing waste by about 60% and utilizing only 1-mL ethanol in the mobile phase. The proposed method is a safer alternative for the simultaneous determination of drugs in their combined pharmaceutical formulation. The method has been validated and compared favorably with a reported one.