Formulation of bioinspired functional hydrogel for the controlled drug release application

Hydrogel is the first biomaterial designed for biomedical use. Polysaccharide based hydrogels are receiving much attention in the past few years, as intelligent materials due to their properties for biomaterials. One of the extensively studied approaches for controlling drug delivery is the encapsulation of drug within polymer chains which sluggish the release on the basis of its crosslinked network. Discontinuous volume variations in hydrogels upon changes of environmental parameters, like polymer composition, temperature, pH, etc., are named multi-responsive hydrogels.

Bioinspired functional hydrogels are prepared using chitosan and polyvinyl pyrrolidone with varying quantities of aminopropyl diethoxy methylsilane via solution casting protocol. Prepared hydrogels were evaluated by different physical and analytical characterization techniques. Swelling indices were examined in distilled water (247.52 g/g), different buffer and electrolyte solutions. Fourier transform infrared spectroscopy was conducted to confirm functional groups and to prove the proposed physical and chemical interactions between polymers and crosslinker. Thermogravimetric analysis was used to assess the response of prepared hydrogels against temperature and found maximum thermal stability up to 23.94% in terms of residue. Contact angle and X-ray diffraction analysis were conducted to investigate the hydrophilicity which was (71°) and crystalline properties, respectively. Extensively, in vitro studies including biodegradation, antimicrobial and cytotoxic properties were examined. Maximum biodegradation was achieved up to 6.4% in seven days and cytotoxicity was 2.64% in terms of mortality using brine shrimp lethality assay. Hydrogels showed antimicrobial properties against E. Coli using liquid diffusion method. Accumulative release of benzocaine was checked in phosphate buffer saline solution at 37 °C at pH 7.4 and observed that almost whole drug was released in 150 min. Hence, based on the aforementioned results, prepared hydrogels are proposed to be used for controlled drug release applications.