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Title: Synthesis and polymerisation of zwitterionic molecules and their evaluation for use as contact lenses and coatings for medical devices
Author: Raisin-Dadre , Fanny
Awarding Body: University of Reading
Current Institution: University of Reading
Date of Award: 2012
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2-Methacryloyloxyethyl phosphorylcholine (MPC) and MPC-containing polymers have been the focus of a significant amount of research as a result of their excellent non-thrombogenic and non-biofouling properties. However, MPC has a major limitation in that the potential for chemical alteration is restricted. A novel zwitterionic molecule was designed and successfully synthesised in the course of this work. The synthesis involved the ring-opening of a cyclic organophosphate with a functionalised tertiary amine bearing a methacrylate functional group. Structural diversity could be introduced by variation of the substitution on the organophosphate by means of nucleophilic substitution. Problems of stability were encountered and overcome with the synt,hesis of a zwitterion exhibiting a slightly elongated spacer between the methacrylate functionality and the quaternary amine. The zwitterions were used as comonomers for the production of crosslinked hydrogels to form soft contact lenses or into linear methacrylic polymers that were intended to be used as coatings for medical devices. The polymeric assemblies were finally evaluated to assess their biocompatibility. Contact lenses were successfully prepared and performed similarly to commercial lenses that contained MPC of equivalent composition. The soft contact lenses were able to absorb a large amount of water and displayed excellent reduction in protein adsorption. Copolymers coated onto polystyrene surfaces demonstrated excellent resistance to the adsorption of fibrinogen and albumin with a stronger resistance profile as the amount of zwitterion was increased in the copolymer. Platelet adhesion ;: was also evaluated; surfaces coated with zwitterionic polymers demonstrated a significant reduction in platelet adhesion and no evidence of their activation was found. Such properties were thought to be attributable to the extremely high water content and interfacial water layer that such polymers are surrounded with.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available