PMID- 34063265
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20210602
LR  - 20210605
IS  - 1424-8220 (Electronic)
IS  - 1424-8220 (Linking)
VI  - 21
IP  - 9
DP  - 2021 May 2
TI  - Detection of Microplastic in Salts Using Terahertz Time-Domain Spectroscopy.
LID - 10.3390/s21093161 [doi]
LID - 3161
AB  - We report on a prototypical study of the detection of microplastic embedded in 
      table salts by using terahertz time-domain spectroscopy. In the experiment, 
      high-density polyethylene (HDPE) of sizes from 150 to 400 mum are used as a 
      representative microplastic and mixed with table salts. Analyzing terahertz 
      transmittance with an effective medium model, we extract various optical 
      properties such as refractive index, absorption coefficient, and real/imaginary 
      parts of the dielectric constant of the mixture. Consequently, the optical 
      properties exhibit volume-ratio-dependence in 0.1-0.5 THz regimes. Especially, 
      the refractive index and the real part of the dielectric constant possess 
      monotonic frequency dependence, meaning that the quantities can be relevant 
      indicators for the detection of the microplastic in terms of practical 
      applications. Our work proves that terahertz time-domain spectroscopy can pave a 
      way to recognize microplastic mixed with salts and be expanded for detecting 
      various micro-sized particles.
FAU - Im, Jaeseung
AU  - Im J
AD  - Department of Physics, Incheon National University, Incheon 22012, Korea.
FAU - Goo, Taewon
AU  - Goo T
AUID- ORCID: 0000-0002-3844-7284
AD  - Department of Physics, Incheon National University, Incheon 22012, Korea.
FAU - Kim, Jugyoung
AU  - Kim J
AD  - Department of Physics, Incheon National University, Incheon 22012, Korea.
FAU - Choi, Soobong
AU  - Choi S
AD  - Department of Physics, Incheon National University, Incheon 22012, Korea.
FAU - Hong, Sung Ju
AU  - Hong SJ
AUID- ORCID: 0000-0003-1318-2141
AD  - Division of Science Education, Kangwon National University, Chuncheon 24341, 
      Korea.
FAU - Bahk, Young-Mi
AU  - Bahk YM
AD  - Department of Physics, Incheon National University, Incheon 22012, Korea.
LA  - eng
GR  - 2019R1G1A1007912/National Research Foundation of Korea/
GR  - Research Assistance Program (2019)/Incheon National University/
GR  - 2020 Research Grant/Kangwon National University/
PT  - Journal Article
DEP - 20210502
PL  - Switzerland
TA  - Sensors (Basel)
JT  - Sensors (Basel, Switzerland)
JID - 101204366
SB  - IM
PMC - PMC8125003
OTO - NOTNLM
OT  - effective medium model
OT  - microplastic
OT  - terahertz time-domain spectroscopy
OT  - terahertz waves
COIS- The authors declare no competing interests.
EDAT- 2021/06/03 06:00
MHDA- 2021/06/03 06:01
PMCR- 2021/05/02
CRDT- 2021/06/02 01:06
PHST- 2021/03/27 00:00 [received]
PHST- 2021/04/29 00:00 [revised]
PHST- 2021/04/30 00:00 [accepted]
PHST- 2021/06/02 01:06 [entrez]
PHST- 2021/06/03 06:00 [pubmed]
PHST- 2021/06/03 06:01 [medline]
PHST- 2021/05/02 00:00 [pmc-release]
AID - s21093161 [pii]
AID - sensors-21-03161 [pii]
AID - 10.3390/s21093161 [doi]
PST - epublish
SO  - Sensors (Basel). 2021 May 2;21(9):3161. doi: 10.3390/s21093161.