Lansoprazole determination in pharmaceutical formulations by flow injection coupled with acidic KMnO4-quinine chemiluminescence system

Abstract

A simple and rapid flow injection chemiluminescence (FI-CL) method based on the reaction of potassium permanganate (KMnO4) and quinine was established for the determination of lansoprazole in pharmaceutical formulations. A linear calibration curve was achieved over the range from 0.01 to 20.0 mg L-1 LNP (R2 = 0.9997 (n = 8); RSD = 1.1 - 3.7% (n = 4)) with a limit of detection of 3.0 × 10-3 mg L-1 (S/N = 3) and injection throughput of 150 h-1. By applying the Student t-test (calculated t-test value: t = 1.059907664, and tabulated t-distributed (95%) = 2.200985) it was found that the proposed method and reported spectrophotometric method were not significantly different. The LNP was efficiently extracted and the recovery of LNP from the spiked pharmaceutical formulations was in the range of 91.0 - 105.9% (%RSD = 1.6 - 3.6, n = 4). No significant interference activity was detected from the excipients commonly found in the drug samples analyzed. The possible chemiluminescence emission mechanism is discussed briefly.