Potentiometric titrations and some complementary optical rotation data are presented for solutions of poly(L-glntamic acid) (PGA) in several H,O-ethanol mixtnres. The data allow the determination of the intrinsic p K (pKo), slope of the apparent pK (pKaPp), versus degree of ionization curves and of
Helix–coil transition kinetics in aqueous poly(α,L-glutamic acid)
✍ Scribed by Arthur L. Cummings; Edward M. Eyring
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1975
- Tongue
- English
- Weight
- 468 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0006-3525
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✦ Synopsis
Abstract
A polarimetric electric‐field‐jump relaxation apparatus is described and used to determine the relaxation spectrum for the helix–coil transition of poly(α,L‐glutamic acid) in water at 24°C. A maximum relaxation time of 1.7 μc occurs at the transition midpoint (pH = 5.9) yielding a rate constant for helical growth of 6 × 10^7^ sec^−1^.
📜 SIMILAR VOLUMES
Water-insoluble films (m. 0.04 X 3 X 30 mm.3 in dried state) of poly-Lglutamic acid (PGA), crosslinked with glycerol or polyvinyl alcohol at pH 4.8, were suspended in aqueous media and their relative lengths meaaured as a function of pH. The film elongate in alkaline pH and contract in acidic pH; th
## Abstract The thermal helix–coil transition of four samples of poly(γ‐benzyl‐L‐glutamate) in the dioxane–dichloroacetic acid (DCA) mixture was studied by optical rotatory dispersion method. The transition occurred at very high DCA content (97.5% by weight) in this system. The transition parameter
In this paper two points are considered: the methods of evaluating the helical content 8 and the calculation of the parameters of the transition from experimental data and its interpretation. The parameter AH obtained is in good agreement with the calorimetric one and v is found to be independent of