“Stable-on-the-Table” Biosensors: Hemoglobin-Poly (Acrylic Acid) Nanogel BioElectrodes with High Thermal Stability and Enhanced Electroactivity

Sensors

Ananta Ghimire²  Omkar V. Zore²  Vindya K. Thilakarathne²  Victoria A. Briand²  Patrick J. Lenehan³  Yu Lei¹  Rajeswari M. Kasi²  Challa V. Kumar² 

[1] Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, USA; E-Mail:;Department of Chemistry, University of Connecticut, Storrs, CT 06269, USA; E-Mails:;Department of Molecular and Cell Biology, University of Connecticut Storrs, Storrs, CT 06269, USA; E-Mail:

关键词: electrochemistry;    biocatalysis;    hemoglobin;    high temperature catalysis;    steam sterilization;    polyacrylic acid;   

DOI  :  10.3390/s150923868

来源: mdpi

【 摘 要 】

In our efforts toward producing environmentally responsible but highly stable bioelectrodes with high electroactivities, we report here a simple, inexpensive, autoclavable high sensitivity biosensor based on enzyme-polymer nanogels. Met-hemoglobin (Hb) is stabilized by wrapping it in high molecular weight poly(acrylic acid) (PAA, M_W 450k), and the resulting nanogels abbreviated as Hb-PAA-450k, withstood exposure to high temperatures for extended periods under steam sterilization conditions (122 °C, 10 min, 17–20 psi) without loss of Hb structure or its peroxidase-like activities. The bioelectrodes prepared by coating Hb-PAA-450k nanogels on glassy carbon showed well-defined quasi-reversible redox peaks at −0.279 and −0.334 V in cyclic voltammetry (CV) and retained >95% electroactivity after storing for 14 days at room temperature. Similarly, the bioelectrode showed ~90% retention in electrochemical properties after autoclaving under steam sterilization conditions. The ultra stable bioelectrode was used to detect hydrogen peroxide and demonstrated an excellent detection limit of 0.5 μM, the best among the Hb-based electrochemical biosensors. This is the first electrochemical demonstration of steam-sterilizable, storable, modular bioelectrode that undergoes reversible-thermal denaturation and retains electroactivity for protein based electrochemical applications.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.