Rapid Detection of Paraquat Pesticide in Honey Using SERS-Based Portable Nanosensing Platform

Rapid determination of trace pesticides in complex food matrices such as honey has been a challenge for sensors research community due to interference signal from the food matrix. In this letter, an optical nanosensing platform to rapidly detect traces of paraquat pesticide in honey is reported. To eliminate the signal interference from honey matrix, Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was employed to isolate paraquat from honey. The QuEChERS method improved the sensor efficacy and enabled the detection of paraquat with limit of detection (LOD) as low as 0.075 mg/kg (75 ppb) in honey. The Raman signal intensity at 1648 cm-1 peak showed a linear relationship with increasing paraquat concentration and exhibited a correlation coefficient R2 equal to 0.9986. The reported method is suitable for deployment in point-of-need applications.