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Updated: Feb 5, 2026

Author Spotlight: Advancing SERS Technology: Au@Carbon Dot Nanoprobes for Label-Free Analysis and Imaging
Published on: June 9, 2023
A novel biosensor based on Au@Ag core-shell nanoparticles for sensitive detection of methylamphetamine with surface
Kang Mao1, Zilei Zhou1, Sheng Han1
1Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
Abstract:
We describe a novel biosensing strategy for sensitive detection of methylamphetamine (MAMP) based on surface enhanced Raman scattering (SERS) by the mediation of spacing between 4-mercaptobenzoic acid (4-MBA) labeled Au@Ag core-shell nanoparticles (Au@Ag). To achieve a favorable SERS substrate, Au@Ag shell-core nanoparticle was synthesized with seeds growth method and well characterized by SEM, TEM and UV-vis spectrometer. The uniform Au@Ag shows an excellent dispersion ability for SERS detection. Under the optimized conditions, the novel biosensor shows a good logarithm linear correlation with the concentration of MAMP ranging from 0.5 ppb to 40 ppb (R2 = 0.986), with a limit of detection at 0.16 ppb of MAMP (3σ). Furthermore, our biosensors hold an excellent selectivity, demonstrated by the negligible interference from the detection of other illicit drugs and metabolites. The concentrations determined with our biosensor from spiked MAMP in human urine sample fell within the same range with the results from mass spectrometry. This indicates that our sensor has a clear potential for the rapid detection of illicit drug in real samples.
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