Sensitive spectrophotometric determination of lansoprazole in pharmaceuticals using ceric ammonium sulphate based on redox and complex formation reactions

Use of picric acid and iodine as electron acceptors for spectrophotometric determination of lansoprazole through a charge-transfer complexation reaction

“…A number of colour formation reactions utilizing different reagents have been employed for the visible spectrophotometric determination of LAN in pharmaceuticals [4,12,40,[44][45][46][47][48][49][50][51][52][53][54][55][56]. The reported methods are based on complexation and oxidative coupling [44], formation of a charge-transfer complex [4,45], redox followed by complexation or colour bleaching [46][47][48][49], bromination [50], ion-pair complexation reaction [51][52][53][54][55] and coupling with diazotized p-nitroaniline [56]. However, most of the reported visible spectrophotometric methods suffer from one or more disadvantages, such as poor sensitivity [4,44,45], a narrow range of determination [47][48][49][50], use of a heating step [44,48], and use of an extraction step [52][53][54][55], as shown in Table 1.…”