Monitoring of adsorption and transfer of organochlorines in soybean seeds and sprouts with mass spectrometric imaging

• Published in: Analytica chimica acta Vol. 1130; pp. 10 - 19
• Main Authors: Yang, Xiaojie, Leng, Xiebin, Qi, Yinghua, Zhang, Juan, Jiang, Ruowei, Li, Weidan, Zhong, Hongying
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-09-2020
• Subjects: Adsorption; Electrons; Environmental pollutants; Food safety; Glycine max; Mass spectrometric imaging; Mass Spectrometry; Persistent organochlorine; Seeds; Structural identification; Persistent organochlorine; Food safety; Environmental pollutants; Structural identification; Mass spectrometric imaging
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2020.07.011

Development of analytical techniques that can monitor the adsorption, transfer and in-situ distribution of environmental pollutants in agricultural products is essential to ensure the implementation of stringent food safety standards for consumer protection. A mass spectrometric imaging approach is described herein to investigate the dynamic changes and spatial distributions of 4, 4′-DDT (dichlorodiphenyltrichloroethane) in soybean seeds and sprouts during the growth. Soy beans seeds incubated in DDT containing water were sliced in every 20 μm and directly blotted on the surface of a compressed thin film of (Bi2O3)0.07(CoO)0.03(ZnO)0.9 nanoparticles. Endogenous molecules and exogenous DDT compounds in soy bean seeds were ionized and dissociated by photoelectrons that are generated on surfaces of semiconductor nanoparticles upon the irradiation of the 3rd harmonic (355 nm) of Nd3+:YAG laser. Structural identification is achieved by the interpretation of fragment ions resulting from electron-initiated specific bond cleavages or hole oxidization. Mass spectrometric images reveal increased quantities of DDT residues in soy bean seeds and sprouts during the growth. It provides an in situ way without extensive sample preparation to monitor the transfer and distribution of exogenous pollutants as well as the possible impacts on plant growth.
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•Monitoring the transfer and bio-accumulation of hazardous compounds.•Mass spectrometric imaging of molecular distribution in soybean seeds.•Structural interpretation with fragment ions.•Ionization of neutral molecules by exothermic photoelectron capture.•Fragmentation through electron-initiated bond cleavages or hole oxidization.