1: Pharm Res. 2006 Sep;23(9):2141-8. Epub 2006 Aug 9. Chemical analysis of solid-state irradiated human insulin. Terryn H, Vanhelleputte JP, Maquille A, Tilquin B. Laboratory of Chemical and Physicochemical Analysis of Drugs (CHAM), Universite Catholique de Louvain, CHAM 72.30, Avenue E. Mounier, 72, B- 1200, Brussels, Belgium. helene.terryn@cham.ucl.ac.be 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. PMID: 16952005 [PubMed - indexed for MEDLINE] Related Links Effect of different gamma radiation doses on solid crystalline insulin: hypoglycaemia in diabetic beagle dogs. [Boll Chim Farm. 2002] PMID:12577519 Electron beam and gamma radiolysis of solid-state metoclopramide. [Pharm Res. 2006] PMID:16741660 Analysis of volatile radiolysis products in gamma-irradiated LDPE and polypropylene films by thermal desorption-gas chromatography-mass spectrometry. [Appl Radiat Isot. 2000] PMID:10697736 The influence of gamma-irradiation upon the chemical and biological properties of insulin. [Pharm Weekbl Sci. 1987] PMID:3302930 A rapid and sensitive method for simultaneous determination of insulin and A21-desamido insulin by high-performance liquid chromatography. [J Pharm Biomed Anal. 2003] PMID:12946530