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The principle of the combined reversed-phase chromatographic electrochemical detection assay of the major serum thyroid hormones is demonstrated. The separation of 3,3',5-triiodothyronine (T(,3)), 3,3',5'-triiodothyronine (rT(,3)) and 3,5,3',5'-tetraiodothyronine (T(,4)) has been studied as a function of solvent strength, pH, temperature and ionic strength. Detection was carried out using a thin-layer electrochemical detection cell set at 1.500 V containing a new material, low temperature isotropic carbon, as a working electrode. This material was evaluated against carbon paste and using it, subnanogram detection limits were noted for the above analytes under defined conditions. Investigation of the feasibility of this analysis applied to 1.0 mL serum samples was carried out using a combined solvent extraction-cation exchange resin clean-up approach. The data indicate that under the defined conditions, elevated total T(,3) levels can be discerned and total T(,4) levels quantitated demonstrating the potential utility of this approach in screening thyrometabolic status.

Ion exchange chromatography methods which have been developed in recent years appear to offer a sensitive technique that can be utilized very advantageously in studies on various proteins and their properties. The application of such a procedure for the successful fractionation of bovine sarcoplasmic proteins should stimulate interest and research in characterizing the changes occurring in beef muscle during the post-mortem aging period. The research described herein pertains to the development and application of a DEAE-cellulose ion exchange chromatography procedure for the fractionation of bovine sarcoplasmic proteins. Results of preliminary experiments indicated that columns packed under pressure possessed superior fractionational qualities than did columns packed without pressure. Also in the preliminary experiments, a Tris buffer system (a starting buffer of 0.04 M Tris phosphate, pH 9.0, and a limiting buffer of 0.5 M Tris H₂PO₄, pH 3.6) and a concave gradient elution procedure were developed which were found to separate the sarcoplasmic proteins satisfactorily. At least 16 components were recognized to be fractionated in the chromatography of beef sarcoplasmic proteins extracted two hours post-mortem. Duplication of the chromatographic results was found to be quite good. Some changes that had occurred in the sarcoplasmic proteins during a post-mortem aging period of 10 days were detected by the chromatographic technique. The changes observed were the appearance of new components, and disappearance of some fractions while others diminished. Data obtained from experiments on the pre-chromatographic treatment of the samples showed that any deviation in procedure always resulted in chromatographic differences. Hence, strict uniformity must be maintained throughout the chromatographic procedure in order to obtain reproducible results. Although the experimental evidence obtained in this study indicates that further research must be completed on the chromatographic procedure, the method does offer a sensitive technique for gaining new information on the properties of the sarcoplasmic proteins. / Graduation date: 1965

Thesis (M.S.)--Rochester Institute of Technology, 1990. / Spine title: Chromatographic retention and donor and acceptor numbers. Typescript. Includes bibliographical references.

Thesis (Ph. D.)--University of Hong Kong, 1997. / Includes bibliographical references (leaves 413-426).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 72-75).

Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2009. / Full text also available online. Scroll down for electronic link.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2010. / Title from title screen (site viewed July 8, 2010). PDF text: x, 259 p. : ill. (chiefly col.) ; 4 Mb. UMI publication number: AAT 3398195. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (Ph. D.)--University of Washington, 1981. / Vita. Bibliography: leaves [131]-135.