Electrochemical Detection of Microplastics in Aqueous Media

Microplastics in aqueous media can be detected through transient oxygen reduction from impacts with an electrified carbon-coated microwire. Each impact is recorded as a spike count in the time domain or as prominent peaks in the frequency domain. The spike count increased from approx. 60 s^-1 (pure solution) to 90 s^-1 (with microplastics) and 230 s^-1 (microplastics in deoxygenated solutions), whereas the frequency domain revealed the presence of spikes in the 7, 21, and 24 Hz regions. The spike count showed a co-variance with the concentration of microparticles, with a linear detection range from 0.02% (<i>w/v</i>) to 0.04% (<i>w/v</i>). The electrochemical sensor, characterized by its simple and cost-effective design, may provide a rapid and user-friendly method for the detection of microplastics.