Urinary free thyroid hormones in children: An assay by gas liquid chromatography

Mansour, Abdelhamid Abdelkadir (1978) Urinary free thyroid hormones in children: An assay by gas liquid chromatography. PhD thesis, University of Glasgow.

Abstract

Due to the trace levels of the free thyroid hormones in urine a variety of methods based on radiochemical techniques have been used for estimating free triiodothyronine aaid thyroxine, viz. competitive protein binding and radioimmunoassaye. While these techniques are currently employed, they suffer certain disadvantages, among which are the cross reaction of the urinary thyroid hormone metabolites with antibody in the radioimmunoassay system (Gaitan et al., 1975) and the competing of these metabolites for binding sites in the competitive-binding system (Finucane, 1976). Additionally, the above methods do not discriminate between bound and free urinary thyroid hormones (Burke & Shakespear, 1976). In this work the use of gas liquid chromatography as a method for the quantitation of urinary thyroid hormones is reported for the first time. Following the addition of thyroxine-2-14C for recovery purposes, aliquots of urine (20ml.) were made acidic by the addition of 5M hydrochloric acid and the thyroid hormones extracted with cation exchange (Dowex 50W-X2(H+/-)) column chromatography (Sterling et al., 1969). Purification of the extracted residues was effected by thin layer chromatography (Chan & Landon, 1972). The dried residues were derivatised by a two-steps method (Hamilton, 1973). First the carboxyl group was methylated with dry methanol in the presenoe of hydrogen chloride gas for 30 minutes at 70

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: W Hamilton
• Keywords: Endocrinology
• Date of Award: 1978
• Depositing User: Enlighten Team
• Unique ID: glathesis:1978-72779
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 11 Jun 2019 11:06
• Last Modified: 11 Jun 2019 11:06
• URI: https://theses.gla.ac.uk/id/eprint/72779