A hybrid system integrating xylose dehydrogenase and NAD coupled with PtNPs@MWCNTs composite for the real-time biosensing of xylose

• Published in: Analyst (London) 2020-08, Vol.145 (16), p.5563-557
• Main Authors: Song, Haiyan, Gao, Guangheng, Ma, Chunling, Li, Yunjie, Shi, Jianguo, Zhou, Xigui, Zhu, Zhiguang
• Format: Article
• Language: English
• Subjects: Biosensing Techniques; Biosensors; Dehydrogenases; Detection; Electrochemical analysis; Electrochemical Techniques; Electrodes; Hybrid systems; Metal Nanoparticles; Multi wall carbon nanotubes; NAD; Nanoparticles; Nanotubes, Carbon; Nicotinamide adenine dinucleotide; Oxidation; Oxidoreductases; Platinum; Polyethylenes; Real time; Regeneration; Selectivity; Sensitivity enhancement; Xylose
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/d0an00880j

The wide application of xylose in the food, beverage, and pharmaceutical industries, as well as in the booming field of biorefinery, raises the demand for a rapid, accurate, and real-time xylose-sensing technique to rival the conventional methods based on chromatography, spectroscopy, and electrochemical analysis using non-specific enzymes or abiotic catalysts. Herein, a hybrid system comprising polyethylene glycerol swing-arm-tethered NAD + and xylose dehydrogenase (XDH), coupled with platinum nanoparticles deposited on carbon nanotubes (PtNPs@MWCNTs), was constructed for the real-time sensing of xylose. The use of the PtNPs@MWCNTs composite enhanced the sensitivity of the electric response and reduced the oxidation potential of NADH significantly. Further, the NAD + immobilization allowed an increase in its microenvironment concentration and facilitated cofactor regeneration. The screen-printed electrode cast with the hybrid system showed a wide xylose detection range of 0.5 to 10 mM or 3.33 to 66.61 mM, and a low detection limit of 0.01 mM or 3.33 mM (S/N = 3), when connected to a potentiostat or a homemade portable biosensor, respectively. The biosensor also exhibited excellent working stability as it retained 82% of its initial performance after 30 days. The analysis of various xylose-containing samples further revealed the merits of our portable xylose biosensor in real-time sensing, including its rapid response, inexpensive instrumentation, and high selectivity, suggesting its great potential in practical applications. A hybrid system comprising of polyethylene glycerol swing arm-tethered NAD + and xylose dehydrogenase, coupled with platinum nanoparticles deposited on carbon nanotubes, was constructed for real-time sensing of xylose.