目前,环境中积累的塑料对水生系统和繁殖它们的活生物体非常关注。在这种情况下,纳米塑料(NPs)被认为是主要和最危险的污染物,因为它们的小尺寸和活性表面,允许它们与各种其他分子相互作用。目前用于检测NP的方法依赖于庞大且昂贵的技术,例如光谱学。在这里我们提议,第一次,一本小说,快,和易于使用的传感器,该传感器基于带有碳纳米管(CNT)半导体(EG-CNTFET)的电解质门控场效应晶体管(EG-FET),用于检测水生环境中的NP,使用聚苯乙烯NP(PS-NP)作为模型材料。特别是,作为EG-CNTFET的工作机制,我们利用了CNT和PS形成非共价相互作用的能力。的确,在我们的EG-CNTFET装置中,NPs和CNT之间的相互作用引起双电层的变化。EG-CNTFET的校正电流(*ION)的线性增加,灵敏度为9.68μA/(1mg/mL),线性检测范围为0.025至0.25mg/mL。假设两种材料之间发生π-π相互作用,如X射线光电子能谱分析所示。使用人造海水作为电解质,为了模仿真实的场景,也观察到*离子的线性增加,灵敏度为6.19μA/(1mg/mL),证明了在更复杂的解决方案中使用开发的传感器的可能性,以及低浓度。这项研究为将来开发用于NP检测和识别的电化学传感器提供了起点。
Plastics accumulating in the environment are nowadays of great concern for aquatic systems and for the living organisms populating them. In this context,
nanoplastics (NPs) are considered the major and most dangerous contaminants because of their small size and active surface, which allow them to interact with a variety of other molecules. Current methods used for the detection of NPs rely on bulky and expensive techniques such as spectroscopy. Here we propose, for the first time, a novel, fast, and easy-to-use sensor based on an electrolyte-gated field-effect transistor (EG-FET) with a carbon nanotube (CNT) semiconductor (EG-CNTFET) for the detection of NPs in aquatic environments, using polystyrene NPs (PS-NPs) as a model material. In particular, as a working mechanism for the EG-CNTFETs we exploited the ability of CNTs and PS to form noncovalent interactions. Indeed, in our EG-CNTFET devices, the interaction between NPs and CNTs caused a change in the electric double layers. A linear increase in the corrected on current (*ION) of the EG-CNTFETs, with a sensitivity of 9.68 μA/(1 mg/mL) and a linear range of detection from 0.025 to 0.25 mg/mL were observed. A π-π interaction was hypothesized to take place between the two materials, as indicated by an X-ray photoelectron spectroscopy analysis. Using artificial seawater as an electrolyte, to mimic a real-case scenario, a linear increase in *ION was also observed, with a sensitivity of 6.19 μA/(1 mg/mL), proving the possibility to use the developed sensor in more complex solutions, as well as in low concentrations. This
study offers a starting point for future exploitation of electrochemical sensors for NP detection and identification.