Raman scattering

Raman spectroscopy

Chemometrics

Statistics

Materials science

Chromatography

Elution

Solid phase extraction

Calibration

Substrate (aquarium)

Geology

Oceanography

Residue (chemistry)

Physics

Extraction (chemistry)

Nanotechnology

Organic chemistry

Mathematics

Optics

Analyte

Analytical Chemistry (journal)

Chemistry

Calibration curve

Nanostructure

Detection limit

The study aimed to extend the applications of surface-enhanced Raman scattering (SERS) – recently one of the most promising and widely employed technique in food safety and quality monitoring – towards determination of two analytes in a single step for the first time. Thus, an ultra-sensitive and selective SERS based detection platform for the simultaneous determination of pesticides namely acetamiprid (AC) and 2,4-dichlorophenoxyacetic acid (2,4-D) in matcha tea has been developed. Owing to the potential interference of different nutrients and pigments in complicated matrices, the matcha tea samples with and without spiking AC and 2,4-D, were percolated through a solid phase extraction cartridge. The eluate was introduced to the SERS Au@Ag nanostructure substrate for monitoring SERS signal with subsequent chemometrics modeling. Under the optimized experimental conditions, a linear calibration exhibited at GA-PLS model with RPD values of 6.53 and 6.23, and Rp values 0.9943 and 0.9923, respectively for AC and 2,4-D. The method was validated in both mixed and single spiking conditions successfully in terms of student's t- and F test at 95% confidence with satisfactory recovery percentages. An RSD value < 4.85% indicates good reproducibility of the proposed method.

Au@Ag nanostructure based SERS substrate for simultaneous determination of pesticides residue in tea via solid phase extraction coupled multivariate calibration