{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/17731"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/17731","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Transition metal complexes of tetracyclines","abstract":"Forty-one transition metals were studied to observe their complexing properties with the tetracyclines. Four metals were found to form sufficiently strong complexes with the tetracyclines to provide a basis for a rapid, reliable method of assaying the potency of the tetracycline products used in medicine today. Microbiological methods take twenty hours to perform; spectrophotometric methods may be completed within one hour. Twenty-eight of the transition metals showed evidence of complex formation with the tetracyclines; not all of these complexes were found to be suitable for the spectrophotometric assay of the tetracyclines, however. The ligand-metal ratios of some of the transition metal-tetracycline complexes were determined under specified conditions using Job's method. In the concentration range for ligand and metal (3 x 10⁻⁵ M), the 1 : 1 complexes appeared to predominate. Attempts were made to identify the binding sites of the metal ions on the tetracycline molecules, using infra-red spectrophotometry, but the results were inconclusive. The stability constant of one of the transition metal-tetracycline complexes was determined by a potentiometric method. Using this method, the result for the titanium-tetracycline complex was β₁= 3,4 x 10¹⁵ M⁻¹.","abstract_html":"Forty-one transition metals were studied to observe their complexing properties with the tetracyclines. Four metals were found to form sufficiently strong complexes with the tetracyclines to provide a basis for a rapid, reliable method of assaying the potency of the tetracycline products used in medicine today. Microbiological methods take twenty hours to perform; spectrophotometric methods may be completed within one hour. Twenty-eight of the transition metals showed evidence of complex formation with the tetracyclines; not all of these complexes were found to be suitable for the spectrophotometric assay of the tetracyclines, however. The ligand-metal ratios of some of the transition metal-tetracycline complexes were determined under specified conditions using Job's method. In the concentration range for ligand and metal (3 x 10⁻⁵ M), the 1 : 1 complexes appeared to predominate. Attempts were made to identify the binding sites of the metal ions on the tetracycline molecules, using infra-red spectrophotometry, but the results were inconclusive. The stability constant of one of the transition metal-tetracycline complexes was determined by a potentiometric method. Using this method, the result for the titanium-tetracycline complex was β₁= 3,4 x 10¹⁵ M⁻¹.","abstract_has_math":false,"creators":["Cunningham, David Graham"],"institution":"Department of Chemistry","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Pay, M H","Fazakerley, G V"],"committee_chairs":[],"committee_members":[],"year":1973,"date_issued":"1973","date_published":"1973","updated_at":"2026-07-22T22:23:18Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/17731","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Pay, M H","Fazakerley, G V"]},{"key":"dc:creator","label":"Author","values":["Cunningham, David Graham"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2016-03-14T07:22:47Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2016-03-14T07:22:47Z"]},{"key":"dc:date.issued","label":"Date","values":["1973"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Chemistry"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Master Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Masters"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["MSc"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/17731"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Forty-one transition metals were studied to observe their complexing properties with the tetracyclines. Four metals were found to form sufficiently strong complexes with the tetracyclines to provide a basis for a rapid, reliable method of assaying the potency of the tetracycline products used in medicine today. Microbiological methods take twenty hours to perform; spectrophotometric methods may be completed within one hour. Twenty-eight of the transition metals showed evidence of complex formation with the tetracyclines; not all of these complexes were found to be suitable for the spectrophotometric assay of the tetracyclines, however. The ligand-metal ratios of some of the transition metal-tetracycline complexes were determined under specified conditions using Job's method. In the concentration range for ligand and metal (3 x 10⁻⁵ M), the 1 : 1 complexes appeared to predominate. Attempts were made to identify the binding sites of the metal ions on the tetracycline molecules, using infra-red spectrophotometry, but the results were inconclusive. The stability constant of one of the transition metal-tetracycline complexes was determined by a potentiometric method. Using this method, the result for the titanium-tetracycline complex was β₁= 3,4 x 10¹⁵ M⁻¹."]},{"key":"dc:title","label":"Title","values":["Transition metal complexes of tetracyclines"]}]}],"canonical_facts":{"dc:contributor.advisor":["Pay, M H","Fazakerley, G V"],"dc:creator":["Cunningham, David Graham"],"dc:date.accessioned":["2016-03-14T07:22:47Z"],"dc:date.available":["2016-03-14T07:22:47Z"],"dc:date.issued":["1973"],"dc:description.abstract":["Forty-one transition metals were studied to observe their complexing properties with the tetracyclines. Four metals were found to form sufficiently strong complexes with the tetracyclines to provide a basis for a rapid, reliable method of assaying the potency of the tetracycline products used in medicine today. Microbiological methods take twenty hours to perform; spectrophotometric methods may be completed within one hour. Twenty-eight of the transition metals showed evidence of complex formation with the tetracyclines; not all of these complexes were found to be suitable for the spectrophotometric assay of the tetracyclines, however. The ligand-metal ratios of some of the transition metal-tetracycline complexes were determined under specified conditions using Job's method. In the concentration range for ligand and metal (3 x 10⁻⁵ M), the 1 : 1 complexes appeared to predominate. Attempts were made to identify the binding sites of the metal ions on the tetracycline molecules, using infra-red spectrophotometry, but the results were inconclusive. The stability constant of one of the transition metal-tetracycline complexes was determined by a potentiometric method. Using this method, the result for the titanium-tetracycline complex was β₁= 3,4 x 10¹⁵ M⁻¹."],"dc:identifier.uri":["http://hdl.handle.net/11427/17731"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Chemistry"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["Transition metal complexes of tetracyclines"],"dc:type":["Master Thesis"],"dc:type.qualificationlevel":["Masters"],"dc:type.qualificationname":["MSc"]},"updated_at":"2026-07-22T22:23:18Z"}