0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Sign in to save

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

Journal of Hazardous Materials 2024 10 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count.
Chao Liu, Yuan Jiao, Junmei Guo, Bo Li, Changxin Gu, Tianwei Qian, Xiaona Liu, Xiaona Liu

Summary

Researchers used fluorescent carbon dots derived from plant leaves to trace how submicrometre plastic particles enter soybean sprouts. The study found that these tiny plastics can be absorbed by plant roots and transported to above-ground tissues, suggesting a pathway for dietary exposure. Evidence indicates that fluorescent labeling with carbon dots is an effective tool for tracking microplastic uptake in food crops.

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/λ: 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.

Share this paper