Highly Sensitive SERS Detection of Neonicotinoid Pesticides. Complete Raman Spectral Assignment of Clothianidin and Imidacloprid

Abstract

The use of Surface Enhanced Raman Spectroscopy in the development of low cost, portable sensor devices that can be used in the field for nitroguanidine neonicotinoid insecticide detection is appealing. However, a key challenge to achieving this goal is the lack of detailed analysis and vibrational assignment for the most popular neonicotinoids. To make progress towards this goal, this paper presents an analysis of the bulk Raman and SERS spectra of two neonicotinoids, namely clothianidin and imidacloprid. Combined with first principles simulations, this allowed assignment of all Raman spectral modes for both molecules. To our knowledge, this is the first report of SERS analysis and vibrational assignment of Clothianidin and a comprehensive assignment and analysis is provided for imidacloprid. Silver nanostructured surfaces were fabricated for qualitative SERS analysis, which provides the characteristic spectra of the target molecules, and demonstrates the ability of SERS to sense these molecules at concentrations as low as 1 ng/L. These detection limits are significantly lower than reported solid state electrochemical techniques and are on a par with high-end chromatographic-mass spectroscopy laboratory methods. These SERS sensors thus allow for the selective and sensitive detection of neonicotinoids, and provides complementary qualitative and quantitative data for the molecules. Furthermore, this technique can be adapted to portable devices for remote sensing applications. Further work focuses on integrating our device with an electronics platform for truly portable residue detection. File list (2) download file view on ChemRxiv SERS Manuscript_preprint 27-3.pdf (1.59 MiB) download file view on ChemRxiv Supporting Information_SERS.pdf (70.54 KiB)

Retracted: A review on the determination of veterinary drug residues in food products

“…Additionally, there are many compounds in both food industry and environment, such as acetamiprid, imidacloprid, thiamethoxam and thiacloprid. Fortunately, this SERS technology could be employed to detect these substances (Creedon et al, 2020;Feng et al, 2019;Xu et al, 2020) with the good results. Therefore, the SERS technique has a wide application in many fields.…”

Applications of surface‐enhanced Raman spectroscopy based on portable Raman spectrometers: A review of recent developments

“…Pesticides are important agricultural production materials for preventing, eliminating and controlling insects, grasses and other harmful organisms which are harmful in the production process of agricultural products. [93][94][95] The pesticides used in the production of agricultural products are mainly divided into four categories: organochlorine, organophosphorus, carbamate and pyrethroid pesticides. However, pesticide residues will pollute environmental water, soil, and atmosphere, etc.…”

Solvent–Antisolvent Competitive Interactions Mediate Imidacloprid Polymorphs in Antisolvent Crystallization

“…In particular, the crystal Form II has a much stronger peak intensity at 320 cm –1 than Form I. The peak at 282 cm –1 corresponds to the rocking vibration of −C8HH–, linking the chloropyridine ring and the imidazolidine ring of IMI; the peak at 320 cm –1 is due to the bending vibration of N9–C10–N11 on the five-membered ring and the nitro group; the peak at 476 cm –1 is due to the rocking vibration of N14C10N11N9 and the twisting vibration of N5C4C6 of IMI; the peak at 751 cm –1 is due to the out-of-plane vibration of the nitro and the rocking vibration of C12HH and C13HH; the peak at 1302 cm –1 corresponds to the bending vibration of C2H and the stretching vibration of the nitro group of IMI; and the peak at 1451 cm –1 represents the stretching vibrations of C1–C2–C3 and C1–N5 on the pyridine ring of IMI. , …”