Elucidating the Degradation Pathways of Human Insulin in the Solid State  

作　　者：Andrew Fagan Lorraine M.Bateman Joseph P.O’Shea Abina M.Crean 

机构地区：[1]SSPC,the SFI Centre for Pharmaceutical Research,School of Pharmacy,University College Cork,Cork T12 YT20,Ireland [2]School of Pharmacy,University College Cork,Cork T12 YT20,Ireland [3]Analytical and Biological Chemistry Research Facility(ABCRF),University College Cork,Cork T12 YN60,Ireland [4]School of Chemistry,University College Cork,Cork T12 YN60,Ireland

出　　处：《Journal of Analysis and Testing》2024年第3期288-299,共12页分析检测（英文）

基　　金：supported in part by a research grant from Science Foundation Ireland(SFI)and is co-funded under the European Regional Development Fund(grant numbers 12/RC/2275(P2)and 18/EPSRC-CDT/3587);the Engineering and Physical Sciences Research Council UK(grant number EP/S023054/1).

摘　　要：While there have been significant advances in the development of peptide oral dosage forms in recent years,highlighted by the clinical and commercial success of approved peptides such as Rybelsus®,there remain several barriers in the way of broad range applicability of this approach to peptide delivery.One such barrier includes the poor physical and chemical stability inherent to their structures,which persists in the solid state although degradation typically occurs at different rates and via different pathways in comparison to the solution state.Using insulin as a model peptide,this work sought to contribute to the development of analytical techniques for investigating common insulin degradation pathways.Chemically denatured,deamidated and aggregated samples were prepared and used to benchmark circular dichroism spectroscopy,reverse phase HPLC and size exclusion chromatography methods for the investigation of unfolding,chemical modifications and covalent aggregation of the insulin molecule respectively.Solid state degraded samples were prepared by heating insulin powder at 60°C and 75%relative humidity for 1,3,5 and 7 d,and the degradation profiles of the samples were evaluated and compared with those observed in solution.While no unfolding was observed to occur,significant deamidation and covalent aggregation were detected.Reductive disulfide bond cleavage using dithiothreitol allowed for separation of the insulin A-and B-chains,offering a facile yet novel means of assessing the mechanisms of deamidation and covalent aggregation occurring in the solid state.

关 键 词：INSULIN Stability Solid state DEAMIDATION Covalent aggregation Disulfide cleavage Biopharmaceutical analysis 

分 类 号：R914[医药卫生—药物化学]