IN VITRO COMPARATIVE COAGULATION STUDIES OF NOVEL BIODEGRADABLE N, O-CARBOXYMETHYLCHITOSAN (NO-CMC) AND OLIGO-CHITOSAN (O-C)

Naturally obtained chitosan biopolymers are increasingly being formulated as bioadhesives due to their hemostatic properties. Comparative studies have been conducted to measure the hemostatic capacity of biodegradable 7% N,O-carboxymetylchitosan (NO-CMC) (with 0.45 mL collagen), 8% NO-CMC, oligo-chitosan (O-C) and oligo-chitosan 53 (O-C 53). Biodegradability (loss of mass) of these chitosans in phosphate-buffered saline (PBS) (0-30 days) and lysozyme (0-14 days) was measured. Blood coagulation ability was observed (0-15 minutes). Coagulation profiles were measured using Coagulation Analyzer. Blood morphologies were assessed through scanning electron microscopy (SEM) and light microscopy (Nikon Eclipse E200). Rapid weight loss was observed in PBS for all the chitosans until the 5^th day, after which the weight remained constant. NO-CMCs were completely degraded by lysozyme by day 12 (p<0.05). Highly deacetylated chitosans (O-C) were observed to degrade slowly. Upon macroscopic observations, NO-CMC promoted erythrocyte aggregation within 7 min. Microscopic analysis showed 7% NO-CMC promoted the most platelet aggregation on its surface, approaching 90% coverage. The current findings contribute substantially to our understanding of all the tested biomaterials that can enzymatically degrade, swell and aggregate erythrocytes and platelets to accelerate hemostasis. Evidence suggests that 7% NO-CMC is the best biodegradable hemostatic agent tested, followed by O-C.