Home
Resources
Publications
Electric Birefringence of Ionized Polypeptides in Solution and the Effect of High Electric Fields on the Helix-Coil Transition

Electric Birefringence of Ionized Polypeptides in Solution and the Effect of High Electric Fields on the Helix-Coil Transition

K Yoshioka, K Kikuchi, M Fujimori

Biophys Chem. 1980 Jun;11(3-4):369-75.

PMID: 16997256

Abstract:

Electric birefringence and circular dichroism measurements have been made on solutions of two po!y (L-lysine) homologs. The specific Kerr constant and the molar ellipticity at 222 nm of poly (L-alpha, gamma-diaminobutyric acid hydrochloride) in methanol/water mixtures underwent an abrupt change between 75 and 80 vol% methanol at 25 degrees C, corresponding to a solvent-induced helix-coil transition. On the helix side of the transition region, i.e., between 78 and 80 vol% methanol, anomalous birefringence transients indicative of field-induced helix-to-coil transition were observed at high fields. In the case of poly (L-ornithine hydrobromide) in methanol/water mixtures, a helix-coil transition was induced between 93 and 98 vol% methanol and anomalous birefringence transients were observed between 96 and 98 vol% methanol. The double logarithmic plots of the steady-state specific birefringence versus the square of field strength for various solvent compositions and polymer concentrations could be superimposed on one another by horizontal and vertical shifts, except for the range where anomalous birefringence transients were observed. This enabled us to estimate the threshold field strength.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP26982218	Poly-L-ornithine hydrochloride		26982-21-8	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: