Gold nanochips with molecularly imprinted polymer coating for sensing explosives: a surface-enhanced Raman scattering approach.

This research is aimed at developing a sensor that is both sensitive and selective for detecting explosives, and to examine its surface-enhanced Raman scattering (SERS) response. Molecularly imprinted polymers (MIPs), commonly used as synthetic receptors in sensors for the selective detection of molecules without prior analytic treatments, have been combined with optical sensors. This integration, especially in combination with localized surface plasmon resonance (LSPR) technology, represents a promising strategy for identifying explosives. Specifically, we considered a sensor based on a gold nanostructure array deposited onto a glass substrate (gold nanochip), followed by the fabrication of an MIP layer using the photochemical polymerization method with 4-nitrophenol (4-NP) as a template molecule. The selectivity of the sensor was assessed by comparing the SERS and LSPR responses against 4-NP and other chemical analogues of nitro-containing explosives. Notably, this technique not only ensures sensor selectivity but is also capable of detecting analytes at concentrations as low as 100 μM.