Physico-chemical characterisation and biological evaluation of freeze dried chitosan sponge for wound care

Haemorrhage is one of the most common cause of mortality if proper action is not taken in a fixed period of time. Over the past three decades, usage of haemostatic materials have been widely introduced for arresting the bleeding. Chitosan is one of the biopolymer which is widely used as a haemostatic agent cross linked using glutaraldehyde and freeze dried to prepare a spongy haemostat. The process of freeze drying has been optimised in a controlled freeze dryer in such a way that we obtain a sponge having good mechanical strength as well as blood absorbing capacity. The morphology and microstructure of the chitosan sponge was observed by scanning electron microscopy (SEM). The chitosan sponge was sterilised using gamma irradiation and sterility studies were carried out to prove the sterile nature of the material. In-vitro cytotoxicity evaluation; in vivo intracutaneous reactivity and Guinea pig maximization test conducted on the gamma irradiated chitosan sponge proved the safety of the chitosan sponge to be suitable for haemostasis.