Extraction Spectrophotometric Determination of Lidocaine Using Flow Injection Analysis

A new flow-through method (flow injection analysis, FIA) for the lidocaine assay, using extraction of ion – associate with bromocresol green, was proposed. The optimum reaction and flow-through conditions (reagent concentrations, pH, flow rates of reagents, injected volume of sample, length of reaction and extraction coil, total flow rate through the separator, withdrawal rate of organic phase) were found. The Lambert-Beer' law is obeyed in the concentration range of 1.4–16.2 μg ml−1.