Glycopolymers for targeted delivery applications
Currently, the area of polymeric drug delivery is one of intense international and interdisciplinary research. Many of the applications of materials derived from this research are focussed on therapeutic applications ultimately to be used in whole body systems. Herein, the research described focuses on a novel application of multicomponent glycopolymers. The majority of pig breading is conducted via artificial insemination. Whilst this offers many advantages, one of the major drawbacks is the adverse effect of oxidation on the spermatozoa during storage (which can be several days) prior to use. The supplementation of vitamin E is highly desirable, however due to its lypophilic character it cannot be added directly to the largely aqueous boar ejaculate mixture. Polymethacrylate derivatives were synthesised carrying carbohydrate residues, vitamin E residues and solubility enhancing amino residues. These vitamin E bearing glycopolymers were found to be soluble in aqueous media. The interactions of these materials with boar spermatozoa were thoroughly investigated. It was demonstrated that supplementation with these glycopolymers significantly reduced cellular oxidation under induced oxidative conditions. Analogous polymers were also synthesised containing a fluorescent dye. Confocal microscopy images were obtained of boar spermatozoa incubated with dye-labelled polymers with and without carbohydrate moieties in order to demonstrate that the internalisation of the polymers was enhanced by carbohydrate-lectin interactions.