An Electron Paramagnetic Resonance (EPR) spectroscopy study on the γ-irradiation sterilization of the pharmaceutical excipient l-histidine: Regeneration of the radicals in solution

Vallotto, C., Williams, H. E., Murphy, Damien M. ORCID: https://orcid.org/0000-0002-5941-4879, Ayres, Z.J., Edge, R., Newton, M.E. and Wedge, C.J. 2017. An Electron Paramagnetic Resonance (EPR) spectroscopy study on the γ-irradiation sterilization of the pharmaceutical excipient l-histidine: Regeneration of the radicals in solution. International Journal of Pharmaceutics 533 (1) , pp. 315-319. 10.1016/j.ijpharm.2017.09.068

Preview

PDF - Accepted Post-Print Version Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (558kB) | Preview

Abstract

The effects of γ-radiation sterilization on the parenteral excipient l-histidine were analysed by means of EPR spectroscopy. The irradiation process was found to induce the formation of a deamination radical which was persistent in the solid state. The nature and reactivity of the radicals following dissolution in water was evaluated using spin-trapping EPR experiments. The deamination radical was found to regenerate in solution in the presence of trace metals, potentially leading to radical induced degradation reactions occurring up to an hour after the dissolution process. Understanding this process is significant for the improved design of parental pharmaceutical formulations in which unwanted radical reactions after γ‐radiation sterilization could lead to degradation of active ingredients.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Chemistry
Publisher:	Elsevier
ISSN:	0378-5173
Funders:	EU
Date of First Compliant Deposit:	1 November 2017
Date of Acceptance:	26 September 2017
Last Modified:	19 Nov 2024 06:30
URI:	https://orca.cardiff.ac.uk/id/eprint/105455

Citation Data

Cited 5 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item