Biosensing at disk microelectrode arrays. Inter-electrode functionalisation allows formatting into miniaturised sensing platforms of enhanced sensitivity.

Biosensor performance depends on the effective functionalisation of a transducer with suitable biorecognition elements. During functionalisation, surface blocking steps are normally carried out to avoid later binding of undesirable molecules and thus guarantee biosensor specificity. However, these blocking steps may be deleterious in electrochemical systems where transduction ultimately relies on electron transfer between the electrode and a redox species in solution.

Detection of Escherichia coli and Salmonella typhimurium using interdigitated microelectrode capacitive immunosensors: the importance of transducer geometry.

This paper presents an immunosensing system to detect Escherichia coli and Salmonella based on electrochemical impedance spectroscopy at interdigitated electrode structures. Our results show the importance of good electrode design in the final detection limit. Four different structures have been fabricated and functionalized.

Gold immuno-functionalisation via self-assembled monolayers: study of critical parameters and comparative performance for protein and bacteria detection.

Surface functionalisation is of extreme importance in assay and biosensor development because it ensures the selective capture and detection of the targets of interest. In the present report, we compare the performance of several gold functionalisation strategies/chemistries, based on SAM self-assembly and Ab conjugation, for protein and bacteria detection. The first part of the work summarises the optimisation of the various protocols considered.