Use this URL to cite or link to this record in EThOS:
Title: Some analytical applications of immobilized enzymes
Author: Trewhella, Martin John
Awarding Body: University of London
Current Institution: Royal Holloway, University of London
Date of Award: 1981
Availability of Full Text:
Access from EThOS:
Access from Institution:
The use of immobilized enzymes in the analytical determination of enzyme substrates, inhibitors and activators has been examined using, for the majority of the work, heat sensors to monitor the chemical reactions occurring. The sensitivity of determination of a wide range of enzyme substrates by such means has been substantially improved over similar, previous reported, work by optimization of a number of relevant parameters (particularly in the choice, and dimensions, of the enzyme support material). Reproducibility of the results in most cases appeared excellent, even over relatively long time periods. A brief study has also been conducted using other types of transducers. Novel techniques for the analytical determination of immobilized enzyme inhibitors and activators have been developed which, although undoubtedly capable of improvement, already show considerable promise. In particular, no reports occur in the literature concerning the use of immobilized enzymes for the quantitative determination of reversible enzyme inhibitors, or enzyme activators. Using these techniques, the determination of enzyme substrates such as penicillin G, urea, hydrogen peroxide, glucose, sucrose, lactose and uric acid have been accomplished, 0.5 cm3 of a 2 x 10-5M solution often being analytically determinable. Enzyme inhibitors (such as Hg2+, Cu2+, caffeine and certain other alkaloids) and activators (such as Cu2+ and Zn2+) have also been determined, in certain cases in concentrations as low as 10-6 - 10 -7 mol dm-3. Additionally, other uses of the combination of immobilized enzymes with thermal detection systems, such as the rapid determination of the overall enthalpies of hydrolysis of urea and penicillinase-sensitive semi-synthetic penicillins have been developed which yield rapid and highly reproducible measurements in an area where little or no data appears in the literature. A correlation has been established between the overall enthalpy of hydrolysis of a semi-synthetic penicillin, and the nature of the side-chain in the 6-amino position of the penicillin. A strong correlation between the relative inhibitory powers of known anti-cholinesterase compounds on soluble and glass-immobilized cholinesterase enzymes has also been demonstrated, suggesting the possibility of using techniques described in this thesis as a rapid initial screening test for the pharmacological activity of new anti-cholinesterase drugs.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: Biochemistry