Highly Sensitive Micellar Enhanced Spectrofluorimetric Method for Determination of Mirtazapine in Tablets and Human Urine: Application to In Vitro Drug Release and Content Uniformity Test

Abstract

A highly sensitive and simple micelle enhanced spectrofluorimetric method was developed for assaying mirtazapine (MRZ) in REMERON® tablets and spiked human urine directly without the need of derivatizing agent. The basis of the current procedure is the examination of the relative fluorescence intensity (RFI) of MRZ in sodium lauryl sulphate (SLS) micellar medium. The RFI of MRZ in water was enhanced markedly on addition of SLS. The RFI was measured at 403 nm after excitation at 320 nm. The fluorescence-concentration relationship was linear over the range 1–500 ng/mL, with lower detection limit of 0.399 ng/mL. The proposed method was successfully applied to the determination of MRZ in dosage form and spiked human urine. Recovery percentages of MRZ utilizing the current method were 99.05±1.83, 98.37±1.96, and 100.41±2.61% for pure powder, pharmaceutical dosage form, and spiked human urine, respectively. The application of the proposed method was extended to test content uniformity and the in vitro drug release of REMERON tablets, according to USP guidelines.