Electric and magnetic properties of the enzyme lysozyme and other biomolecules

Ahmed, NAG 1976, Electric and magnetic properties of the enzyme lysozyme and other biomolecules , PhD thesis, University of Salford.

PDF Restricted to Repository staff only until 31 July 2024. Download (4MB) | Request a copy

Abstract

Measurements of the dielectric properties of lysozyme and other biomolecules have been made. The results of these measurements showed that the permittivity and loss are dependent on the temperature,humidity and applied electric and magnetic fields. Investigations of the effect of applied electric fields on the permittivity and loss of these materials led to the conclusion that they might possess a metastable state having a high electric dipole moment. The possibility of the existence of such states has been suggested theoretically by Frohlich (1973, 1975). The dependence of the dielectric constant of the enzymes lyso^yme and trypsin on magnetic field strength was such that a magnetic field of the order of 600 gauss resulted in large changes in the dielectric constant. For a 0.1% by weight solution of lysozyme in water the observed changes were about 30% (too large to be due to liquid crystal anisotropy) at frequencies from 2 kHz to 100kHz. Preliminary measurements of the magnetic susceptibility were carried out using a torsion balance. These showed large values of diamagnetic susceptibility at certain magnetic field strengths which were also very dependent on the temperature, humidity, pH values and the concentration of solutions. The results of these measurements suggest that superconducting regions might exist in biomolecules at biological temperatures (Ahmed et al 1975, 1976). These results were repeated on a Faraday susceptibility balance and Cahn R.G. microbalance. The results confirm those obtained previously and showed that the oxygen might play some part in the observed effect. Thin lysozyme films were found to be deposited on the inner walls of the containers and these showed similar effects to the lysozyme solutions themselves. This led to the conclusion that the effects observed might be partially due to lysozyme deposits on the walls of the containers. An investigation into the possibility of the existence of Josephson supercurrents in biomolecules at biological temperatures was carried out using thin film techniques. It was found in the preliminary experiments that Al-Al-O - lysozyme - Pb junctions gave a number of effects of the kind being sought. The results showed a number of interesting features which occurred when pairs of junctions were bridged together; hysteresis behaviour in the I-V curves which disappeared at certain magnetic field strengths, a step like behaviour in the I-V curve when junctions were placed inside an X-bcind waveguide with no external source of radiation; current peaks formed on the I-V characteristics at certain magnetic field strengths and voltages. Similar measurements were carried out using a point contact lysozyme - Al disc junction in a section of X-band waveguide. Irradiating the junction with microwaves resulted in the disappearance of an ohmic behaviour in the I-V curve. The voltage across the junction decreased from millivolts to microvolts.

Item Type:	Thesis (PhD)
Contributors:	Smith, CW (Supervisor)
Schools:	Schools > School of Computing, Science and Engineering
Depositing User:	Institutional Repository
Date Deposited:	03 Oct 2012 13:34
Last Modified:	04 Aug 2022 11:28
URI:	https://usir.salford.ac.uk/id/eprint/26501

Actions (login required)

Edit record (repository staff only)