Biosensor Approach by UV Spectrophotometric Detection

Abstract

This study investigates using consumable media and new materials for developing low-price and simple detection schemes for point-of-care diagnostics. We have previously investigated the application of cellulose dialysis tubing (dialysis membrane) as a biosensor scaffold medium for the forthcoming protein detection by UV spectrophotometry (1, 2). This was achieved by using minute amount of protein, either in solution or in blood serum, after drying only 0.5 µl of sample on the membrane surface. The outcomes proved the feasibility of this approach as a novel method for the recognition of bovine serum albumin (BSA) and blood serum proteins. However, standard deviations seemed to be high, which revealed the necessity of optimizations. Here it is shown that standard deviations diminish significantly, when dialysis membrane tubing is eliminated and the sample is dried directly on the quartz cuvette of the spectrophotometer. Tests were performed with BSA protein and the detection limit was found to be 5 µM, which corresponds to 165 ng of protein.