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. 2019 Apr 24;20(8):2017.
doi: 10.3390/ijms20082017.

Feasibility of Laser-Induced Breakdown Spectroscopy and Hyperspectral Imaging for Rapid Detection of Thiophanate-Methyl Residue on Mulberry Fruit

Di Wu  1 , Liuwei Meng  2 , Liang Yang  3 , Jingyu Wang  4 , Xiaping Fu  5 , Xiaoqiang Du  6   7 , Shaojia Li  8 , Yong He  9 , Lingxia Huang  10   11
Affiliations

Feasibility of Laser-Induced Breakdown Spectroscopy and Hyperspectral Imaging for Rapid Detection of Thiophanate-Methyl Residue on Mulberry Fruit

Di Wu et al. Int J Mol Sci. .

Abstract

An effective and rapid way to detect thiophanate-methyl residue on mulberry fruit is important for providing consumers with quality and safe of mulberry fruit. Chemical methods are complex, time-consuming, and costly, and can result in sample contamination. Rapid detection of thiophanate-methyl residue on mulberry fruit was studied using laser-induced breakdown spectroscopy (LIBS) and hyperspectral imaging (HSI) techniques. Principal component analysis (PCA) and partial least square regression (PLSR) were used to qualitatively and quantitatively analyze the data obtained by using LIBS and HSI on mulberry fruit samples with different thiophanate-methyl residues. The competitive adaptive reweighted sampling algorithm was used to select optimal variables. The results of model calibration were compared. The best result was given by the PLSR model that used the optimal preprocessed LIBS-HSI variables, with a correlation coefficient of 0.921 for the prediction set. The results of this research confirmed the feasibility of using LIBS and HSI for the rapid detection of thiophanate-methyl residue on mulberry fruit.

Keywords: chemometrics; hyperspectral imaging; laser-induced breakdown spectroscopy; mulberry; pesticide residue; variable selection.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Typical LIBS profiles of the control group and pesticide residue group of mulberry fruit with two concentrations of the pesticide solution (0 g mL−1 and 0.0001 g mL−1).
Figure 2
Figure 2
Typical Vis-NIR (visible and near infrared reflectance) hyperspectral profiles measured based on (a) system I and (b) system II for uncontaminated mulberry samples and samples contaminated with fungicide residue (concentrations of the fungicide solutions used in the samples from groups 1 to 6 were 0 g mL−1, 0.0050 g mL−1, 0.0025 g mL−1, 0.0017 g mL−1, 0.0013 g mL−1, and 0.0001 g mL−1).
Figure 3
Figure 3
PCA plots using the LIBS data (a) before preprocessing and (b) after preprocessing, and the LIBS data combined with the HSI data (c) before preprocessing and (d) after preprocessing (concentrations of the pesticide solutions used in the samples from groups 1 to 6 were 0 g mL−1, 0.0050 g mL−1, 0.0025 g mL−1, 0.0017 g mL−1, 0.0013 g mL−1, and 0.0001 g mL−1).
Figure 4
Figure 4
A typical LIBS analysis system setup.
See this image and copyright information in PMC

References

    1. Kim A.-J., Kim M.-W., Woo N.-R.-Y., Kim S.-Y., Kim H.-B., Lim Y.-H., Kim M.-H. Study on the nutritional composition and antioxidative capacity of mulberry fruit (Ficus-4x) Korean J. Food Sci. Technol. 2004;36:995–1000.
    1. Sánchez M.T., Flores-Rojas K., Guerrero J.E., Garrido-Varo A., Pérez-Marín D. Measurement of pesticide residues in peppers by near-infrared reflectance spectroscopy. Pest Manag. Sci. 2010;66:580–586. doi: 10.1002/ps.1910. - DOI - PubMed
    1. Li Y.-F., Qiao L.-Q., Li F.-W., Ding Y., Yang Z.-J., Wang M.-L. Determination of multiple pesticides in fruits and vegetables using a modified quick, easy, cheap, effective, rugged and safe method with magnetic nanoparticles and gas chromatography tandem mass spectrometry. J. Chromatogr. 2014;1361:77–87. doi: 10.1016/j.chroma.2014.08.011. - DOI - PubMed
    1. Tong H., Tong Y., Xue J., Liu D., Wu X. Multi-residual pesticide monitoring in commercial Chinese herbal medicines by gas chromatography–triple quadrupole tandem mass spectrometry. Food Anal. Meth. 2014;7:135–145. doi: 10.1007/s12161-013-9609-5. - DOI
    1. Leandro C.C., Hancock P., Fussell R.J., Keely B.J. Ultra-performance liquid chromatography for the determination of pesticide residues in foods by tandem quadrupole mass spectrometry with polarity switching. J. Chromatogr. 2007;1144:161–169. doi: 10.1016/j.chroma.2007.01.030. - DOI - PubMed