ZIF-8-wrapped AgNPs modified with β-cyclodextrin for sensitive detection of thiacloprid and imidacloprid by SERS technology.

The high efficient surface-enhanced Raman scatterring (SERS) methods to detect thiacloprid and imidacloprid were established using ZIF-8-wrapped Ag nanoparticles (AgNPs) modified with β-cyclodextrin (β-CD). The substrate of ZIF-8/β-CD@AgNPs was characterized by ultraviolet visible spectra (UV-vis), thermogravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). The interaction between the substrate and thiacloprid/imidacloprid was also explored. The optimum measurement conditions were obtained by response surface model based on single-factor experiments. Enhancement factors (EFs) of thiacloprid and imidacloprid were respectively 2.29 × 10 ⁶ and 2.60 × 10 ⁶ . A good linearity between the scattering intensity and the concentration of thiacloprid/imidacloprid within 3-1000 nmol L ^-1 /6-400 nmol L ^-1 was established. The interference experiments indicated that the methods had good selectivity. The SERS methods were successfully applied to detect thiacloprid and imidacloprid in several vegetables samples. The recoveries ranged from 95.5 % to 105 % (n = 5). The detection limits (LODs) (S/N = 3) for thiacloprid and imidacloprid were 1.50 and 0.83 nmol L ^-1 , respectively.
Competing Interests: Declaration of competing interest We would like to submit the enclosed manuscript entitled “ZIF-8-wrapped AgNPs modified with β-cyclodextrin for sensitive detection of thiacloprid and imidacloprid by SERS technology”, which we wish to be considered for publication in “Talanta”. No conflict of interest exits in the submission of this manuscript, and manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part.
(Copyright © 2024 Elsevier B.V. All rights reserved.)