Prolonged protein immobilization of biosensor by chemically cross-linked glutaraldehyde on mixed cellulose membrane

Abstract

Abstract Protein immobilization studies with high protein binding sensitivity are of primary concern for any bio-sensing applications. In the present study, glutaraldehyde (GA) was utilized to chemically cross-link with the cellulose compound in mixed cellulose (MC) membrane and the protein molecules. Optimal cross-linking process on membrane was determined statistically and corresponded responses of protein immobilization were described through a quadratic empirical model. Field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) micrographs and thermogravimetric analysis (TGA) have demonstrated the successful deposition of GA on membranes. The optimum GA integration process condition was found at 3 wt% of GA on a single layer and 30 min of integration time, with protein binding predicted at 896.6 μg/cm3. The experimental validation was conducted at this optimum condition, and the result was found at 911.9 μg/cm3, with standard deviation of 1.6%. This small error confirms the adequacy of the empirical model and its ability to predict the GA-protein immobilization performances.