Functionalization of carbon buckypaper for the sensitive determination of hydrogen peroxide in human urine

作者：Chatterjee Sanghamitra; Chen Aicheng^*

来源：Biosensors and Bioelectronics, 2012, 35(1): 302-307.

DOI：10.1016/j.bios.2012.03.005

• Biosensor
• Buckypaper
• Horseradish peroxidase
• Hydrogen peroxide
• Human urine

Here we report on a new approach for the electrochemical detection of hydrogen peroxide (H2O2) based on the co-immobilization of horseradish peroxidase and methylene blue on the functionalized carbon buckypaper supported by a titanium substrate. Cyclic voltammetry was used to study and optimize the performance of the resulting electrochemical biosensor. The proposed biosensor exhibited high analytical performance towards the quantification of H2O2 at the physiological pH 7.4. Under optimized conditions, the biosensor shows a wide linear response range from 0.1 x 10(-6) to 5 x 10(-4) M concentrations of H2O2. The detection limit was determined to be 7.5 x 10(-8) M (based on S/N = 3). Reproducibility and stability of the fabricated biosensor were examined with satisfactory results. The biological relevance of the developed electrochemical biosensor has been further studied by the determination of H2O2 in human urine samples of normal volunteers prior to and following the ingestion of coffee. Increased levels of urinary H2O2 concentration suggest that oxidative stress is induced by coffee drinking in humans. There is considerable interest in oxidative stress as relates to human physiology. The sensitive determination of H2O2 in human urine may serve as a valuable biomarker to effectively elucidate specific levels of oxidative stress in vivo.

• 出版日期2012-5-15