The pretreatment method in marine organisms and sediment for microplastics analysis by FTIR using "Cylindrical microplastics fractionator"

Hiraku Tanoiri; Eduardo Estevan Barrientos; Haruka Nakano; Hisayuki Arakawa; Masashi Yokota

doi:10.1016/j.mex.2023.102396

The pretreatment method in marine organisms and sediment for microplastics analysis by FTIR using "Cylindrical microplastics fractionator"

MethodsX. 2023 Sep 23:11:102396. doi: 10.1016/j.mex.2023.102396. eCollection 2023 Dec.

Authors

Hiraku Tanoiri¹, Eduardo Estevan Barrientos^{1

2}, Haruka Nakano³, Hisayuki Arakawa¹, Masashi Yokota¹

Affiliations

¹ Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan.
² Science Department, Faculty of Science and Technology, University of Belize, Hummingbird Avenue P.O. Box 340, Belmopan, Belize.
³ Research Institutions of Applied Mechanics, Kyusyu University, 6-1 Kasuga-Koen, Kasuga, Fukuoka 816-8580, Japan.

Abstract

For the detection of microplastics (MPs) in aquatic biota using Fourier transform infrared spectroscopy (FTIR), the ability to remove organic matter (OM) in pretreatment steps is essential to increase the time efficiency of MPs measurement and method uniformity. In principle, decreasing OM can be achieved by increasing the number of pretreatment steps. However, MPs are lost in proportion to the number of transfers between each step. Therefore, we have created a "Cylindrical MPs Fractionator" composed of commercially available materials. This container allows for a six-step pretreatment process that is designed to increase the removal capacity of OM with only one transfer to prevent the loss of MPs.•Biological or sediment samples are placed in the extractor and subjected to chemical treatment and density separation.•Residues containing MPs are obtained on filters by vacuum filtration.•After additional chemical treatment of the obtained residue, the components of the residue are identified by microscopic FTIR.This method removed 99.3% of OM and recovered 88.5% of MPs. The presenting method confirmed that this can be used with the same process for 11 organisms and sediments from estuarine ecosystem in Japan as models.

Keywords: Chemical digestion; Density separation; Estuarine; MPs pretreatment method for aquatic organisms and sediment; Marine organisms; Plastic pollution; QA/QC; Time efficiency; Unified method.