The creation of a biosensor based on chitosan entails a series of steps. Initially, chitosan is dissolved in an acidic solution, followed by the addition of the desired enzyme or biomolecule to the solution. Subsequently, the mixture is applied onto an appropriate substrate, such as a glassy carbon electrode, and permitted to undergo drying. The resulting film is then cross-linked using a suitable cross-linking agent, such as glutaraldehyde, to enhance the stability of the biosensor.