Article ID Journal Published Year Pages File Type
11027673 Biosensors and Bioelectronics 2018 25 Pages PDF
Abstract
An improved amperometric sarcosine biosensor was constructed based on covalent immobilization of sarcosine oxidase nanoparticles (SOxNPs) onto gold electrode (AuE). The SOxNPs/AuE was characterized by scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy and electrochemical impedance spectroscopy (EIS) at different stages of its construction. The biosensor worked optimally within 2 s at a potential of 1.0 V, against Ag/AgCl, pH 6.5 and 35 °C. A linear relationship was observed between sarcosine concentration range, 0.1-100 μM and the biosensor response i.e. current in mA under optimum conditions. The biosensor offered a low detection limit of 0.01 μM and gratifying storage stability. The SOxNPs/AuE was unaffected by a number of serum substances at their physiological concentrations. The biosensor measured sarcosine level in sera collected from persons suffering from prostate cancer (mean13.5 μM, n = 8), which was significantly higher (p < 0.01) than those in apparently healthy persons (mean 2.2 μM, n = 8). The SOxNPs/Au electrode was reused 300- times during the span of 180 days, with only 10% loss in its initial activity while being stored dry at 4 °C.
Related Topics
Physical Sciences and Engineering Chemistry Analytical Chemistry
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