Hélène Terryn1, Jean-Paul Vanhelleputte, Aubert Maquille, Bernard Tilquin. 1. Laboratory of Chemical and Physicochemical Analysis of Drugs (CHAM), Université Catholique de Louvain, CHAM 72.30, Avenue E. Mounier, 72, B- 1200, Brussels, Belgium. helene.terryn@cham.ucl.ac.be
Abstract
PURPOSE: To study the chemical modifications induced upon irradiation of solid human insulin at radiosterilization doses and investigate the influence of the absorbed dose on radiolysis. MATERIALS AND METHODS: Volatile radiolytic products were monitored by gas chromatography coupled with mass spectrometry (GC-MS) and non-volatile products by two different high performance liquid chromatography (HPLC) methods: the formation of higher molecular weight proteins was assessed by size exclusion liquid chromatography whereas assays for related compounds and chemical potency tests were carried out using reverse-phase HPLC-UV. Conformational changes were investigated by measurements of circular dichroism. RESULTS: After gamma irradiation at 10 kGy, the recovery of insulin was 96.8%; higher molecular weight proteins accounted for 0.35% (relative peak area) and other related compounds (including A21 desamido insulin) represented 1.29%. No major structural changes and no volatile radiolytic compounds were detected. CONCLUSION: Human insulin samples irradiated in the solid-state at 10 kGy (gamma rays) and 14 kGy (electron-beam) meet the European Pharmacopoeia requirements and can be considered as quite stable towards radiation from a chemical analysis viewpoint.
PURPOSE: To study the chemical modifications induced upon irradiation of solid humaninsulin at radiosterilization doses and investigate the influence of the absorbed dose on radiolysis. MATERIALS AND METHODS: Volatile radiolytic products were monitored by gas chromatography coupled with mass spectrometry (GC-MS) and non-volatile products by two different high performance liquid chromatography (HPLC) methods: the formation of higher molecular weight proteins was assessed by size exclusion liquid chromatography whereas assays for related compounds and chemical potency tests were carried out using reverse-phase HPLC-UV. Conformational changes were investigated by measurements of circular dichroism. RESULTS: After gamma irradiation at 10 kGy, the recovery of insulin was 96.8%; higher molecular weight proteins accounted for 0.35% (relative peak area) and other related compounds (including A21 desamido insulin) represented 1.29%. No major structural changes and no volatile radiolytic compounds were detected. CONCLUSION:Humaninsulin samples irradiated in the solid-state at 10 kGy (gamma rays) and 14 kGy (electron-beam) meet the European Pharmacopoeia requirements and can be considered as quite stable towards radiation from a chemical analysis viewpoint.
Authors: Manuel Correia; Maria Teresa Neves-Petersen; Per Bendix Jeppesen; Søren Gregersen; Steffen B Petersen Journal: PLoS One Date: 2012-12-05 Impact factor: 3.240