particle sorbent

in microextraction
https://doi.org/10.1351/goldbook.10273

Extraction phase in the form of sorbent particles.

Note: Particles are typically of a nanometre size and applied in the dispersion mode of extraction.
Source:
PAC, 2016, 88, 517. (Glossary of terms used in extraction (IUPAC Recommendations 2016)) on page 547 [Terms] [Paper]