The development of novel, rapid and inexpensive methods for the detection of bacteria will be beneficial in many fields including food and water safety, biosecurity, bioprocess control and clinical diagnostics. Of the possible alternatives, biosensors offer great potential to replace or complement traditional culture-based detection methods, which are time consuming, expensive and need equipped laboratories and trained staff.
Molecularly-imprinted polymers (MIPs) are bio-inspired artificial receptors that are finding increasing use in biosensors. Unlike bio-receptors, they are more stable, inexpensive and easy to produce. Although imprinting of chemical and biological molecules has been very well studied, there is limited work on the imprinting of whole bacterial cells.
Bacterial cells are well-known to present several sugar compounds on their outer surface. In this paper, we explore the reversible interaction between boronic groups and diols for the development of highly specific MIPs for intact bacterial cells. 3-aminophenylboronic acid-based MIPs, for the detection of Staphylococcus epidermidis, were fabricated via chronoamperometric methods and SEM images were used to verify the successful capturing and releasing of the whole bacterial cells. Successful capture and easy release of the bacterial cells, via a competitive approach, was demonstrated. Furthermore, the usefulness of this imprinting process for the specific detection of Staphylococcus epidermidis versus non-target bacteria, Staphylococcus aureus and Streptococcus pneumoniae, was also demonstrated by the use of impedance spectroscopy measurements of bacterial binding to MIPs and NIPs (non-imprinted polymers) electrodes.
2nd International Congress on Biosensors – BiosensorTR2015, 10-12 June 2015, Izmir, Turkey.