US 12,465,927 B2
Method for detecting nanoplastics in ecosystem using vertical nanogap electrode and raman spectroscopy
Yong-Sang Ryu, Seoul (KR); Eui-Sang Yu, Seoul (KR); and Eui Tae Jeong, Seoul (KR)
Assigned to Korea Institute of Science and Technology, Seoul (KR)
Filed by KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed on Nov. 2, 2022, as Appl. No. 17/979,249.
Claims priority of application No. 10-2022-0047704 (KR), filed on Apr. 18, 2022.
Prior Publication US 2023/0333083 A1, Oct. 19, 2023
Int. Cl. B03C 5/02 (2006.01); B82Y 15/00 (2011.01); G01N 27/447 (2006.01)
CPC B03C 5/022 (2013.01) [B82Y 15/00 (2013.01); G01N 27/44791 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A method for detecting a nanoplastic using a vertical nanogap electrode and a Raman spectroscopic device, comprising:
in a state where a vertical nanogap electrode is provided in aquatic environment in which a nanoplastic exists, forming a nanoplastic aggregate having a size larger than a laser wavelength of a Raman spectroscopic device, by applying an alternating voltage of a specific frequency to the vertical nanogap electrode to collect and concentrate the nanoplastic in a collector of the vertical nanogap electrode,
irradiating the nanoplastic aggregate with the Raman spectroscopic device, and
performing Raman spectroscopy on the nanoplastic aggregate concentrated in the collector of the vertical nanogap electrode to detect the nanoplastic constituting the nanoplastic aggregate,
the alternating voltage and a frequency of the corresponding alternating voltage are controlled so that a local minimum point of potential energy acting on the vertical nanogap electrode is located in a central region of the collector of the vertical nanogap electrode,
the local minimum point of the potential energy acting on the vertical nanogap electrode due to interaction between AC-electroosmosis (ACEO) and dielectrophoresis (DEP) is located in the central region of the collector of the vertical nanogap electrode,
in the aquatic environment in which the nanoplastic exists, a minimum size of the nanoplastic is 200 nm, and a limiting of detection (LoM) of the nanoplastic is 4.66 mg/L.