Improvement of Low-Cost Commercial Carbon Screen-Printed Electrodes Conductivities with Controlled Gold Reduction Towards Thiol Modification

Abstract

Effectively detecting bacteria in the environment is crucial for researchers to make informed decisions about the safety of public areas, such as lakes. This led to an increased need in the development of portable handheld devices, capable of on-the-spot chemical and biological sensing applications. Specific interests lie in electrochemical biosensors and screen-printed electrodes (SPEs) due to the decreased costs, an ability to integrate with handheld devices, and their user-friendly nature. Together, these qualities make the devices more accessible in resource-poor settings. Two of the most common substrates used to fabricate SPEs are carbon and gold. Carbon SPEs are effective in sensing applications yet challenged when attempting to covalently attach biomolecules to the surface. Gold SPEs have higher affinity towards biomolecules and improve the sensitivity, selectivity, and stability of a device; yet they can be costly. A carbon SPE modified with gold may be an ideal candidate to create an efficient low-cost device, using electrochemical gold deposition. In this study, electrochemical gold deposition on SPEs is explored to enhance the surface area and conductivity towards sensing applications. These SPEs were then modified with a thiol-based self-assembled monolayer (SAM) which demonstrates this technique could be used for further modification towards biosensing.