Performance Comparison of Aptamer- and Antibody-Based Biosensors for Bacteria Detection on Glass Surfaces

Antibodies are the most common ligands in commercial and research assay systems for detecting whole pathogen cells. On the other hand, aptamers are superior ligands with many advantages over antibodies in sensitive and robust assay development. Extensive comparisons between aptamer-based biosensors and immunosensors are limited to protein analytes. Here, we report a comparison of ligands (four antibodies and one aptamer for each bacteria) to be used as a biosensor for Escherichia coli and Staphylococcus aureus on glass surfaces through systematic experiments. We have demonstrated that anti-E. coli antibody and mouse monoclonal to S. aureus have the best performance among the compared ligands. Hence, the ligands with the best performance were further investigated within the scope of linear range, analytical sensitivity, and reproducibility of the results. We have demonstrated that anti-E. coli antibody with a capture efficiency of 89.1% and mouse monoclonal to S. aureus with a capture efficiency of 88.2% have the best performance among the compared ligands. The results suggest that antibody ligands function with higher efficiency than aptamer ligands but aptamers have strong potential as an analytical tool.