On-line photochemical derivatization and flow-injection spectrophotometric determination of ergonovine maleate

Abstract A flow-injection manifold is proposed for the on-line photochemical derivatization of ergonovine maleate with application to pharmaceutical formulations. The procedure is based on the reaction with p-dimethylaminobenzaldehyde in presence of iron(III) and sulphuric acid medium. The reaction rate is improved by irradiation of the solution with a mercury lamp (254.0 nm). The calibration graph is linear over the range 3–74 μg ml−1 ergonovine, with a mid-range R.S.D. of 1.7% and a sample throughput of 34 h−1. The influence of foreign compounds was tested.