Abstract
Sequential injection chromatography (SIC) is based on a stopped-flow approach utilizing microscale low-pressure pump and selection valves coupled with micro-scale fiber optic spectrometric devices. In the current communication, a new method for the estimation of furosemide (FSD) and amiloride (AMD) in tablet formulation exploiting SIC is reported. The method was reverse-phase liquid chromatographic-based. The separation was carried out onto C18 monolithic column (4.6 x 50 mm) with a mobile phase composition of 25 mM phosphate buffer (pH 4.0)-acetonitrile (65: 35, v/v). Other conditions were: sample volume 30 mu L, flow rate 30 mu L/s and UV detection at 283 nm. The SIC method is eco-friendly and cost-effective. The volume of consumed mobile phase was 3.25 mL. The sample frequency was 24 samples/h. The assay also exhibited linear dynamic ranges of 10-100 mu g/mL for FSD and 5-80 mu g/mL for AMD. Acceptable intra- and inter-day precision (the RSD values were less than 2.2%) as well as accuracy (the recovery range was 97.5-98.4%) were obtained for concentrations over the range of the standard curves. The procedure was established for the purpose of quality control at a pharmaceutical laboratory.