Green-modified micellar liquid chromatography for isocratic isolation of some cardiovascular drugs with different polarities through experimental design approach

Highlights: • Innovating of bilayer pseudo-phase stationary phase in micellar liquid chromatography. • Employing a new green modifier in micellar liquid chromatography. • Simultaneous isocratic isolation of hydrophilic and hydrophobic compounds in human plasma samples. • Introducing a reliable chromatographic system for retaining polar species. - Abstract: Bilayer pseudo-stationary phase micellar liquid chromatography (MLC) was developed for simultaneous isocratic isolation of hydrochlorothiazide, as a basic-polar (hydrophilic) cardiovascular drug, as well as triamterene and losartan potassium, as acidic-nonpolar (hydrophobic) cardiovascular drugs. Utilizing a deep eutectic solvent (DES), as a novel green mobile phase additive in combination with acetonitrile (ACN) and acetic acid (ACA), drastically improved the chromatographic behavior of the drugs. Concentration of sodium dodecyl sulphate (SDS), as well as volume percentages of ACN, DES, and ACA were optimized by using a central composite design. The optimal composition of the mobile phase (0.12 mol L⁻¹ SDS, 5% ACN, 4% DES, and 2% ACA) was chosen through the desirability function. The chromatographic peaks of both hydrophilic and hydrophobic drugs, respectively, emerged at high and low retention time values in the shortest total analysis time of 20 min (at a flow rate of 2 mL min⁻¹). Analytical characterization of the developed approach was investigated through Food and Drug Administration (FDA) guidelines. Applicability of the method was evaluated by analysing of human plasma samples which were directly injected into the system.