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Lab-on-chip to detect diazepam

Researchers have developed a paper-based sensor that can be used to detect excess dose of diazepam, a drug used to treat depression and anxiety1.

Besides treating depression and anxiety, diazepam is misused for recreational purposes. Overdose can cause harmful side-effects such as blurred vision, unconsciousness, stomach upset, rashes and weakness. Existing methods for detecting this drug are complex and time-consuming.

Scientists from the Amity University in Noida and Maharshi Dayanand University in Rohtak, India fabricated the sensor by depositing silica-coated gold nanorods on a paper matrix. They then tested its efficiency to detect the drug in human urine samples through electrochemical studies.

With increase in drug concentration, the sensor showed an increase in current. The sensor offers a functionalised platform for miniaturisation and is more economical compared to the other electrodes used before.

The sensor eliminates the need for a large experimental set-up, reducing the size of the sensing chip.

“This sensor can be used as a lab-on-chip platform for the detection of diazepam, including other drugs and metabolites in forensic applications,” says lead author, Jagriti Narang.



  1. Narang, J. et al. Lab on paper chip integrated with Si@GNRs for electroanalysis of diazepam. Anal. Chim. Acta. 980, 50-57 (2017)

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