A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science
6 February 2017, Johannesburg. / Polymorphism is not only limited to single component systems. Co-crystals have exhibited polymorphism and various polymorphic co-crystals have been reported. Polymorphism in co-crystals presents an expansion of the optimization space around a pharmaceutical compound and also offers the opportunity to develop novel patentable material. Polymorphism of pharmaceutical co-crystals was investigated by means of an exhaustive data mining survey and the formation of polymorphic co-crystals. The search was performed using the Cambridge Structural Database (CSD). The search aimed to find and tally neutral pharmaceutical co-crystals which are polymorphic. The survey of the CSD showed that 14% of the pharmaceutical co-crystals were polymorphic. The co-crystal of theophylline and 3,4-dihydroxybenzoic acid was found to be polymorphic and the novel polymorph was synthesized and characterized. The co-crystals were characterized by x-ray crystallographic techniques and Differential Scanning Calorimetry. The single crystals of carbamazepine and cinnamic acid was grown and characterized by SCXRD for the first time. The single crystal data was able to show that the hydrogen bonding packing that was modelled in the literature is incorrect. / MT2017
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:wits/oai:wiredspace.wits.ac.za:10539/22734 |
| Date | January 2017 |
| Creators | Mnguni, Malitsatsi Jesse |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | Online resource (xi, 64 leaves), application/pdf |
Page generated in 0.002 seconds