doi:10.1038/nindia.2011.15 Published online 31 January 2011
Researchers have designed a versatile nanoscale sensor that can detect traces of cholesterol, sugar and uric acid in biological samples. The sensor could also be used to detect minute amounts of hydrogen peroxide.
Platinum nanoparticles look promising as alternatives to gold nanoparticles for the fabrication of biosensors. Sensing hydrogen peroxide has received much attention because it is a marker for cellular stress and has been linked to aging and severe human diseases such as cancer and cardiovascular disorders.
To design an effective biosensor for detecting cholesterol, sugar and hydrogen peroxide, the researchers used platinum nanoparticles and oxidase enzyme with a silicate network derived through the sol–gel method.
The sensor was able to detect hydrogen peroxide in the presence of common interfering agents such as ascorbic acid, uric acid and paracetamol. In addition, the sensor was stable, did not undergo deactivation and could be used for repeated measurements.
The researchers found that the sensor responded well to glucose, uric acid and cholesterol at lower concentrations, while reaching saturation at higher concentrations. Practical applications of any biosensor require a fast response time — the response time of this sensor was around two seconds.