Pad Printing of Carbon Electrodes with Argon Plasma Activation as a Simple and Low Temperature Manufacturing Process for Antibody‐Type Biosensors

Abstract

Abstract In diagnostic tools, rapid in vitro tests such as COVID‐19 antigen or pregnancy tests are gaining significance for identifying various pathologies or health conditions. This shift contributes to a change in the way diagnostic efforts are carried out, emphasizing decentralized approaches that offer valuable services within communities, yielding long‐term advantages for the healthcare system. Considering the substantial quantity of these tests manufactured and used annually, a straightforward manufacturing process is proposed for highly sensitive carbon electrodes designed for antibody‐type biomarker sensors. This process, utilizing pad printing – an additive, low‐temperature, and cost‐effective method, coupled with plasma activation – has proven the electrodes capability to measure interferon gamma protein, a tuberculosis biomarker. Using electrochemical impedance spectroscopy, the electrodes display high sensitivity and are capable of measuring concentrations from 10 to 1000 pg mL−1 in undiluted serum within an hour. The sensor, utilizing solely a monolayer of antibodies, achieves a performance equivalent to that of a commercial standard sandwich ELISA tested in this study.

Keywords

• biosensors
• carbon electrodes
• electrochemical impedance spectroscopy
• functionalization
• immunosensors
• near‐patient testing, pad printing