Nitric Oxide Detection Using Electrochemical Third-generation Biosensors - Based on Heme Proteins and Porphyrins

Nitric oxide radical (NO) is a signalling molecule involved in virtually all forms of life. Its relevance has been leading to the development of different analytical methodologies to assess the temporal and spatial fluxes of NO under the complex biological milieu. Third‐generation electrochemical biosensors are promising tools for in loco and in vivo NO quantification and, over the past years, heme proteins and porphyrins have been used in their design. Since there are some limitations with the biorecognition element directly adsorbed onto the electrode surface, nanomaterials (carbon nanotubes, gold nanoparticles, etc.) and polymers (cellulose, chitosan, nafion®, polyacrylamide, among others) have been explored to achieve high kinetics and better biosensor performance. In this review, a broad overview of the field of electrochemical third‐generation biosensors for NO electroanalysis is presented, discussing their main characteristics and aiming new outlooks and advances in this field.FG and LBM thank FCT/MCTES for the fellowship grants SFRH/BD/52502/2014 and SFRH/BPD/111404/ 2015, respectively, which are financed by national funds and co-financed by FSE. CMC acknowledges FCTMCTES funding through project PTDC/BBB-BQB/ 0129/2014 (FCT/MCTES). This work was supported by the PTDC/BB-BQB/0129/2014 project (FCT/MCTES) and also by the Associate Laboratory Research Unit for Green Chemistry – Technologies and Processes Clean – LAQV, financed by national funds from FCT/MEC (UID/QUI/50006/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01- 0145-FEDER-007265). Funding through REQUIMTE project entitled “NOR-based biosensor for nitric oxide detection in biological and environmental samples” is also acknowledged.