Direct Quantification of Nanoplastics Neurotoxicity by Single‐Vesicle Electrochemistry

Abstract

Nanoplastics are recently recognized as neurotoxic factors for the nervous systems. However, whether and how they affect vesicle chemistry (i.e., vesicular catecholamine content and exocytosis) remains unclear. This study offers a first direct evidence on the nanoplastics‐induced neurotoxicity at a single‐cell level by single‐vesicle electrochemistry. We observe the cellular uptake secretion of polystyrene (PS) nanoplastics into model neuronal cells and mouse primary neurons, leading to cell viability loss depending on nanoplastics exposure time and concentration. By using single‐vesicle electrochemistry, we find the reductions in the vesicular catecholamine content, the frequency of stimulated exocytotic spikes, the neurotransmitter release amount of single exocytotic event, and the membrane‐vesicle fusion pore opening‐closing speed. Mechanistic investigations suggest that PS nanoplastics can cause disruption of filamentous actin (F‐actin) assemblies at cytomembrane zones and change the kinetic patterns of vesicle exocytosis. Our finding shapes the first quantitative, multi‐spatiotemporal picture of high concentration of nanoplastics‐induced neurotoxicity at a single‐cell level.

Universal Covalent Grafting Strategy of an Aptamer on a Carbon Fiber Microelectrode for Selective Determination of Dopamine In Vivo

“…Under KCl stimulation, the current first rises sharply, producing spike I within 30 s and then falls to baseline as dopamine is rapidly metabolized, and the stimulus-generated dopamine is 6.5–7.6 μM [ I (nA) = 0.16 C DA (μM) + 0.06, r = 0.9998]. Interestingly, reproducible shoulder spike II (1.0–1.2 μM) is generated during the current drop, which behaves similarly to the kinetic process of the neurotransmitter release from vesicles via exocytosis. − Similarly, Zhang et al recently showed that such double spikes occurred when neighboring vesicles aggregate to form a dimer and that the distance between the vesicles correlated with the separation of the double spikes. Furthermore, they also recorded complex events in high K + -stimulated PC12 cells, such as single spikes, double spikes, and even multispikes.…”