Defense Arlina Prima Putri: "Functionalized Arginate for Biomedical Appliation"

Promotors: Prof. Francesco Picchioni and Prof. Erik Heeres

Abstract: Alginates are one of the natural polysaccharides that are found in numerous applications in biomedical science and engineering. Alginates are attractive for wound healing, tissue engineering, and drug delivery applications. This is due to the favorable properties of alginates, including biocompatibility, low toxicity, abundant availability, and ease of gelation. Chemical functionalization like oxidation is one potential way to generate alginate derivatives with low molecular weight. In this research the ratio of oxidation agent and sodium alginate as substrate was studied. The oxidation reaction was leads to pyran ring opening and the formation of di-aldehyde, the so-called alginate dialdehyde (ADA) as much as 0.82 and 0.12 mol of aldehyde per mol repeating unit of alginate. The advantages of ADA are a lower molecular weight and a newly formed active aldehyde functional groups, both were depended on the degree of oxidation. The new available functional groups open the new opportunity to conduct reductive amination reaction to graft new targeting branch on alginate structure. This reaction could conduct using sodium cyanoborohydride, sodium borohydride, and picoline borane complex. The new formed polymer product can be formed as hydrogel either used Schiff base reaction with gelatin to form crosslinking or with ionic crosslinker like calcium chloride. The resulted hydrogel is shear-thinning and self-healing, makes it suitable for biomedical application. The grafting study of ADA with plant lectin Wheat Germ Agglutinin (WGA), generated a microgel product that suitable for curcumin encapsulation. The cytotoxicity study demonstrated that the microgels at low concentrations were suitable for the drug delivery matrix.

Dissertation