Utilising Commercially Fabricated Printed Circuit Boards as an Electrochemical Biosensing Platform

Abstract

Printed circuit boards (PCBs) offer a promising platform for the development of electronics-assisted biomedical diagnostic sensors and microsystems. The long-standing industrial basis offers distinctive advantages for cost-effective, reproducible, and easily integrated sample-in-answer-out diagnostic microsystems. Nonetheless, the commercial techniques used in the fabrication of PCBs produce various contaminants potentially degrading severely their stability and repeatability in electrochemical sensing applications. Herein, we analyse for the first time such critical technological considerations, allowing the exploitation of commercial PCB platforms as reliable electrochemical sensing platforms. The presented electrochemical and physical characterisation data reveal clear evidence of both organic and inorganic sensing electrode surface contaminants, which can be removed using various pre-cleaning techniques. We demonstrate that, following such pre-treatment rules, PCB-based electrodes can be reliably fabricated for sensitive electrochemical biosensors. Herein, we demonstrate the applicability of the methodology both for labelled protein (procalcitonin) and label-free nucleic acid (E. coli-specific DNA) biomarker quantification, with observed limits of detection (LoD) of 2 pM and 110 pM, respectively. The proposed optimisation of surface pre-treatment is critical in the development of robust and sensitive PCB-based electrochemical sensors for both clinical and environmental diagnostics and monitoring applications.

Portable electroanalytical nucleic acid amplification tests using printed circuit boards and open-source electronics

“…S10 †), also showing no degradation due to edge effects. 48 The target concentration that we tested (1 pM) corresponds to 1500 microalgal cells/reaction, provided that one cell of O. cf. ovata has 2137 ribosomal DNA copies per cell.…”

“…The gold layer of standard commercial PCBs is around 65–100 nm, which was not thick enough to produce reproducible electrochemical measurements. Although a thicker gold layer can also be included during the industrial manufacturing of PCBs, 48 it increases its price drastically and it is difficult to order at a small scale. In this study, we therefore, cleaned their surface and subsequently modified them by conducting an in-house gold electroplating (Experimental section) to achieve a gold layer with a thickness of roughly 2 μm according to the manufacture specifications.…”

“…Furthermore, PCBs offer the possibility to be easily integrated into sensors, actuators, and electronics. The interest of using PCBs as electrodes for DNA sensing is growing, [44][45][46][47][48] but no device has been yet applied to the detection of isothermally amplified DNA.…”

Biocompatibility Study of a Commercial Printed Circuit Board for Biomedical Applications: Lab-on-PCB for Organotypic Retina Cultures

“…Although printed circuit board (PCB) substrates are typically used for electronics, the development of devices based on PCB substrates has been the subject of increasing research over the years [1,2]. The reason for this lies in the advantages that PCB implies for biomedical applications and marketability [3,4], such as low cost, commercial availability, and the possibility of integrating electronic circuits with ease.…”

Editorial for the Special Issue on Lab-on-PCB Devices

“…Therefore, the achievement of a robust development of biosensor using PCB substrates is mandatory for a successful future of lab-on-PCB devices. In this respect, the work reported in [ 11 ] provide a very good guide for fabricating PCB-based electrochemical biosensors. The authors analyzed the critical technological considerations, allowing the use of Printed Circuit Boards as reliable electrochemical sensing platforms.…”