A STUDY OF THE CONFORMATIONAL STABILITY OF PROTEINS IN HYDROFLUOROALKANE PROPELLANTS USING FT-RAMAN SPECTROSCOPY.

A STUDY OF THE CONFORMATIONAL STABILITY OF PROTEINS IN HYDROFLUOROALKANE PROPELLANTS USING FT-RAMAN SPECTROSCOPY.
?.?.Quinn1 , R.T.Forbes1 , A.C.Williams1 , M.J.Oliver2 and T.S.Purewal2 .
1Drug Delivery Group, Postgraduate Studies in Pharmaceutical Technology, School of Pharmacy, University of Bradford, Bradford BD7 1DP
2 Inhalation Development, 3M Healthcare Ltd, Loughborough, Leics. LE11 1EP
3M Drug Delivery Systems
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Summary
Due to the inherent structural instability of proteins, the development of CFC-free MDI formulations containing biomolecules is beset with numerous challenges. In assessing the conformation of proteins in any medium, both secondary and tertiary structures need to be elucidated. This study evaluates the use of FT-Raman spectroscopy to probe protein conformational stability in HFAs. Analysis of Raman spectra provided structural information on the peptide backbone, disulfide bonds and C-C stretching vibrations, enabling the conformation of model proteins (?-galactosidase and hen egg lysozyme) in various physical states to be determined. Initial results revealed differences between the in-canister interaction of HFAs and the model proteins, when compared in the unprocessed and lyophilised states. These findings suggest that this technique may be a useful tool for optimization of protein MDI formulations.
References
1.Pace, C.N. (1975) Crit. Rev. Biochem., 3:1-43.
2 Jacob, J., Krafft, C., Welfle, K., Welfle H. and Saenger, W., (1998) Acta Crystall., 54: 74-80.
3.Areas, E.P.G, Ribeiro, M.C.C., and Santos P.S., (1996) J. Mol. Struct., 378: 111-119.
4.Wilson, G., Hecht, L. and Barron, L.D. (1996) Biochem., 35: 12518-12528.