Surface nanodroplet-based nanoextraction from sub-milliliter volumes of dense suspensions

TL;DR

This paper introduces a green, rapid nanoextraction method using surface nanodroplets for analyzing dense suspensions, achieving high sensitivity without toxic solvents, applicable to environmental and biomedical samples.

Contribution

The study presents a novel nanoextraction technique that efficiently extracts and detects analytes from dense suspensions without pre-removal of solids or toxic solvents.

Findings

Achieved a detection limit of 10^(-9) M for fluorescent analytes.

Extraction efficiency remains high even with 30 wt% particles.

Method is applicable to complex wastewater and biomedical samples.

Abstract

Cleaner analytic technique for quantifying compounds in dense suspension is needed for wastewater and environment analysis, chemical or bio-conversion process monitoring, biomedical diagnostics, food quality control among others. In this work, we introduce a green, fast, one-step method called nanoextraction for extraction and detection of target analytes from sub-milliliter dense suspensions using surface nanodroplets without toxic solvents and pre-removal of the solid contents. With nanoextraction, we achieve a limit of detection (LOD) of 10^(-9) M for a fluorescent model analyte obtained from a particle suspension sample. The LOD lower than that in water without particles 10^(-8) M, potentially due to the interaction of particles and the analyte. The high particle concentration in the suspension sample thus does not reduce the extraction efficiency, although the extraction process was slowed down up to 5 min. As proof of principle, we demonstrate the nanoextraction for quantification of model compounds in wastewater slurry containing 30 wt% sands and oily components (i.e. heavy oils). The nanoextraction and detection technology developed in this work may be used as fast analytic technologies for complex slurry samples in environment industrial waste, or in biomedical diagnostics.