Optical detection of fat and adulterants concentration milk using TMDC (WS2 and MoS2)-surface plasmon resonance sensor via high sensitivity and detection accuracy

Abstract

This paper introduces a surface plasmon resonance sensor for milk fat and melamine concentration detection, utilizing a transition-metal dichalcogenide (TMDC: WS2 and MoS2) based framework and incorporating an Ag–Pd bimetallic layer. The aim is to provide an innovative approach to monitor fat and melamine levels in milk. The palladium layer offers chemical stability and enhances sensitivity alongside the TMDC layer. Compared to the conventional SPR sensor, the maximum sensitivity, and detection limit are 409.36, 248.96°/RIU, and 0.0085, 0.0140 RIU, for detection of fat and melamine as sensing layer, respectively, related to the WS2 layer. The sensivity of sensor was expanded, due to the expanded field concentrated and profundity of infiltration of the sensor layer, coming about in a bigger interaction volume. The existence of the WS2 layer, with its notable imaginary component of the dielectric constant, enhances sensitivity while simultaneously enlarging the SPR curves. This study concludes that TMDC-Ag-Pd, offer a highly sensitive and efficient means of detecting fat cancentrion and melamine of milk. These findings suggest that TMDC-Ag-Pd optical sensor have great promise for application in the food industry.