Rapid Trace Detection of Pesticide Residues on Tomato by Surface-Enhanced Raman Spectroscopy and Flexible Tapes

Figure 4

SERS signal of characteristic peaks with (a–c) different AuNPs concentrations, (d–f) different coagulants, (g–i) different AuNPs dosages, and (j–l) different NaCl dosages. (m) Summary of optimal parameters for each pesticide. CK represents the group without coagulants. (a), (d), (g), (j) The results of thiabendazole; (b), (e), (f), (k) the results of carbendazim; (c), (f), (i), (l) the results of chlorpyrifos. Different color depths represent different characteristic peaks. Bars and points indicate the means ± standard deviation of eight replicates. Within the same characteristic peak, any two bars or points with different letters are statistically significant according to ANOVA (Tukey post hoc test,  < 0.05).

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