Novel Microneedle Patch-Based Surface-Enhanced Raman Spectroscopy Sensor for the Detection of Pesticide Residues

Pesticide residues are a global threat to human health, and conventional sensors fail to simultaneously detect pesticide residues on the surface and inside agricultural products. In this work, we present a new microneedle (MN) patch-based surface-enhanced Raman spectroscopy (SERS) sensor. The needles and the basement of MNs can simultaneously detect pesticide residues on the surface and inside agricultural products. The Ag nanoparticles and sodium hyaluronate/poly(vinyl alcohol) (HA/ PVA) hydrogel used in this MN patch-based sensor efficiently amplify the Raman signals of the pesticide residues. In addition, the HA/PVA hydrogel can effectively and quickly collect the residues, allowing this sensor to detect pesticide residues more conveniently. Furthermore, the stepped structure of the MNs increases the sensor's surface area. Experimental results show that the sensor can detect thiram and thiabendazole (TBZ) pesticide residues with detection limits of 10-7 and 10-8 M, respectively. The detection process is minimally invasive and not harmful to agricultural products. The application of this MN patch-based SERS sensor can be extended to the safety and health monitoring of other plants and animals.

Automated summary

Pesticide residues pose a global threat to human health, and conventional sensors are unable to detect them on both the surface and inside agricultural products simultaneously. In this study, a new microneedle patch-based surface-enhanced Raman spectroscopy (SERS) sensor is introduced, which can detect pesticide residues on both the surface and inside agricultural products using needles and the basement. The Ag nanoparticles and sodium hyaluronate/poly(vinyl alcohol) (HA/PVA) hydrogel in this sensor amplify the Raman signals of pesticide residues and enable convenient collection. The stepped structure of the microneedles increases the sensor's surface area. The sensor has been shown to detect thiram and thiabendazole (TBZ) pesticide residues with detection limits of 10-7 and 10-8 M, respectively. The detection process is minimally invasive and harmless to agricultural products. The application of this microneedle patch-based SERS sensor can be extended to the safety and health monitoring of other plants and animals.