Tracing the entry process of submicrometre plastics in soybean sprouts by leaf-derived fluorescent carbon dots

Chao Liu; Yuan Jiao; Junmei Guo; Bo Li; Changxin Gu; Tianwei Qian; Xiaona Liu

doi:10.1016/j.jhazmat.2024.134272

Tracing the entry process of submicrometre plastics in soybean sprouts by leaf-derived fluorescent carbon dots

J Hazard Mater. 2024 May 15:470:134272. doi: 10.1016/j.jhazmat.2024.134272. Epub 2024 Apr 10.

Authors

Chao Liu¹, Yuan Jiao¹, Junmei Guo¹, Bo Li¹, Changxin Gu¹, Tianwei Qian², Xiaona Liu³

Affiliations

¹ College of Environmental Science and Engineering, Taiyuan University of Technology, Shanxi Key Laboratory of Earth Surface Processes and Resource Ecological Security in Fenhe River Basin, Shanxi Engineering Research Center of Low Carbon Remediation for Water and Soil Pollution in Yellow River Basin, Jinzhong 030600, China.
² College of Environmental Science and Engineering, Taiyuan University of Technology, Shanxi Key Laboratory of Earth Surface Processes and Resource Ecological Security in Fenhe River Basin, Shanxi Engineering Research Center of Low Carbon Remediation for Water and Soil Pollution in Yellow River Basin, Jinzhong 030600, China. Electronic address: qiantianwei@tyut.edu.cn.
³ College of Environmental Science and Engineering, Taiyuan University of Technology, Shanxi Key Laboratory of Earth Surface Processes and Resource Ecological Security in Fenhe River Basin, Shanxi Engineering Research Center of Low Carbon Remediation for Water and Soil Pollution in Yellow River Basin, Jinzhong 030600, China. Electronic address: liuxiaona@tyut.edu.cn.

PMID: 38613953
DOI: 10.1016/j.jhazmat.2024.134272

Abstract

As a global emerging contaminant, microplastics (MPs) in water or soil can accumulate in vegetables, making them easily ingested through the diet. With excellent and tunable optical properties, carbon dots (CDs) are highly advantageous for tracing the entry process of MPs. Originally, long-wavelength CDs were synthesized from leaf-derived extracts, and fluorescent submicrometer plastics (CDs-MPs) with clean surfaces and concentrated particle sizes were obtained by soap-free microemulsion polymerization. The concentration of CDs-MPs exhibits a significant linear relationship with long-wavelength fluorescence intensity (λ_Ex/λ_Em: 415/676 nm). Soybean sprouts (SBS), as an important type of food, are susceptible to contamination of MPs due to their soft epidermis and rapidly growing biomass. The results showed that CDs-MPs could be embedded into the cortex of SBS and enter the plant with cell division and elongation, leading to an increase in pore size on the cell wall surface. After entering the root system, CDs-MPs will pass through the Casparian strip and migrate in the vessels. Then, CDs-MPs enter the leaves through vascular bundles, and the distribution and size of epicuticular wax on leaves have changed. Furthermore, SBS showed resistant growth and increased levels of oxidative response when exposed to MPs/CDs-MPs. It is the first study to demonstrate the application of leaf-derived CDs in the prevention of MPs pollution by revealing the migration behavior of submicrometre plastics in SBS.

Keywords: Carbon dots; Fluorescent tracing; Long-wavelength emission; Microplastics; Soybean sprouts.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Carbon* / chemistry
Fluorescence
Glycine max* / chemistry
Microplastics / toxicity
Particle Size
Plant Leaves* / chemistry
Plant Roots
Plastics / chemistry
Quantum Dots* / chemistry

Substances

Carbon
Microplastics
Plastics