The molecular-weight dependence of the rms radius of gyration »R 2 g … 1/2 of poly(gbenzyl L-glutamate ) (PBLG) in helicogenic solvents shows negative and positive deviations from expectations for an intact and rigid a-helix in the higher and lower molecular-weight ranges, respectively. In order to
Solvent effects on the orientaion of naphthalene rings in the side chain of poly-γ-1-naphthylmethyl-L-glutamate
✍ Scribed by Akihiko Ueno; Fujio Toda; Yoshio Iwakura
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1974
- Tongue
- English
- Weight
- 358 KB
- Volume
- 13
- Category
- Article
- ISSN
- 0006-3525
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✦ Synopsis
Abstract
The orientation of naphthalene rings in the side chain of poly‐γ‐1‐naphthylmethyl‐L‐glutamate (PNLG) in mixed solvents of dichoroethane (DCE) and hexafluoroisopropanol (HFIP) has been studied together with its conformation by infrared, circular dichroism, and fluorescence spectra. The CD pattern of PNLG varies with the solvent composition while it maintains the α‐helical conformation. The fluorescence spectra of PNLG in solution show excimer emission of the naphthalene chromophores. The ratio of intensity of the excimer emission to that of the normal fluorescence decreases as the HFIP component in the solvent increases. It is suggested that the naphthalene rings in the side chain of α‐helical PNLG are more rigidly orientated in the solvents of higher HFIP ratio.
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