PHOTOCHEMICAL-FLUOROMETRIC DETERMINATION OF FOLIC-ACID IN A MULTICOMMUTATED FLOW SYSTEM

A flow system based on multicommutation was developed for the determin ation of folic acid by fluorimetry following irradiation by ultraviole t light. The photochemical reaction was carried out in a reaction coil . Insertion of time-controlled sample volumes enabled the determinatio n of a wide range of concentrations without changing the manifold desi gn, which makes it suitable for application to automated dissolution s tudies. An automated system control selects for each sample, depending on its concentration, the sampling time and therefore the most conven ient sample volume. Linear calibration plots were obtained over a conc entration range from 0.1 to 40.0 mg l(-1) with a relative standard dev iation of less than 3% and a sampling rate of about 25 samples per hou r. (C) 1997 Elsevier Science B.V.