Stability of Cholesterol; Cholesterol-5ÃÂ²,6ÃÂ²-Epoxide; Cholesta-3,5-Dien-7- One, and 5ÃÂ±-Cholestane in Solution During Short-Term Storage
- *Corresponding Author:
- Annie J King
Department of Animal Science
University of California
One Shields Avenue
Davis, CA 95616, USA
Tel: (530) 752-7150
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Received date: October 10, 2012; Accepted date: October 20, 2012; Published date: October 25, 2012
Citation: Busch TP, Gross HB, King AJ (2012) Stability of Cholesterol; Cholesterol- 5β,6β-Epoxide; Cholesta-3,5-Dien-7-One, and 5α-Cholestane in Solution During Short-Term Storage. J Chromat Separation Techniq 3:147. doi:10.4172/2157-7064.1000147
Copyright: © 2012 Busch TP, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Because cholesterol and its oxide products (COPs) are used as standards during analysis, their stability and autoxidation were assessed under typical storage conditions. Individual toluene solutions of cholesterol; cholesterol- 5β, 6β-epoxide; cholesta-3,5-dien-7-one; and 5α-cholestane were prepared and aliquots were stored at 23 ± 2°C, 4°C, and -20°C for 7 days. Samples were removed from storage, dried under nitrogen, derivatized and analyzed using gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. β-sistosterol and 5-colest-ene-7-one were found to be a suitable recovery internal standard and an instrument internal standard, respectively. All compounds in solution had no detectable artifact generation during 7 days of storage; thus, they were stable. Storage temperatures of 23 ± 2°C, 4°C, and -20°C did not affect stability. Chromatograms revealed contaminants and other peaks likely associated with incomplete derivatization of some compounds; potential causes for the unusual lack of derivitization are discussed.