Phenazines and Polyphenazines in Electrochemical Sensors and Biosensors

Abstract

Phenazine dyes and their polymers are reviewed with respect to their application in electrochemical sensors and biosensors, for which they are finding increasing application as redox mediators due to their unique redox and also chromatic properties, being used for the development of (bio)sensors for direct or indirect analyte determination. Electrocatalytic effects decrease the overpotential of a number of important analytes and help increase sensitivity and decrease the detection limit, in some cases, allowing the simultaneous determination of several analytes; their properties as redox mediators can be improved when combined with carbon nanotubes. Future perspectives are indicated.

Keywords:

• Biosensors
• Electrochemical sensors
• Phenazines
• Polyphenazines

This article was submitted as part of a Special Memorial Issue honoring Prof. George G. Guilbault.

Financial support from Fundação para a Ciência e a Tecnologia (FCT), PTDC/QUI/65255/2006 and PTDC/QUI/65732/2006, POCI 2010 (co-financed by the European Community Fund FEDER) and CEMUC® (Research Unit 285), Portugal is gratefully acknowledged. R. Pauliukaite and M. E. Ghica thank FCT for postdoctoral fellowships SFRH/BPD/27075/2006 and SFRH/BPD/36930/2007, respectively, and M. M. Barsan for a doctoral grant, SFRH/BD/27864/2006.

Notes

Abbreviations: AcB – acetate buffer; AlcDH – alcohol dehydrogenase; AlcOx – alcohol oxidase; AldDH – aldehyde dehydrogenase; BIA – batch injection analysis; CV – cyclic voltammetry; DHP – dihexadecyl phosphate; DPV – differential pulse voltammetry; FIA – flow injection analysis; GA – glutaraldehyde; GDH – glucose dehydrogenase; GlK – glycerol kinase; GlPOx – glycerol 3-phosphate oxidase; GOx – glucose oxidase; Hb – haemoglobin; HRP – horseradish peroxidase; LSV – linear sweep voltammetry; MWCNT – multi walled carbon nanotubes; NADH – nicotine adenine dinucleotide reduced form; NADHOx – NADH oxidase; PB – phosphate buffer; PBS – phosphate buffer saline; PMalG – poly(malachite green); PNRNWs – poly(neutral red) nanowires; PVAc – polyvinyl acetate; PyrOx – pyruvate oxidase; RRDE – rotating ring disc electrode; SCE – saturated calomel electrode; SWCNT – single walled carbon nanotubes; UV-VIS – ultraviolet-visible.