Towards rapid extracellular vesicles colorimetric detection using optofluidics-enhanced color-changing optical metasurface

TL;DR

This paper introduces a rapid, colorimetric method for detecting extracellular vesicles using an innovative combination of optofluidics and optical metasurfaces, enabling quick, low-concentration sensing with simple read-out tools.

Contribution

It presents a novel integration of metasurface optics with optofluidics for fast, low-cost EV detection without spectrometers, improving sensitivity and response time.

Findings

Detects EVs at concentrations as low as 10^7/ml

Achieves detection within two minutes

Allows naked eye or CCD read-out

Abstract

Efficient transportation and delivery of analytes to the surface of optical sensors are crucial for overcoming limitations in diffusion-limited transport and analyte sensing. In this study, we propose a novel approach that combines metasurface optics with optofluidics-enabled active transport of extracellular vesicles (EVs). By leveraging this combination, we show that we can rapidly capture EVs and detect their adsorption through a color change generated by a specially designed optical metasurface that produces structural colors. Our results demonstrate that the integration of optofluidics and metasurface optics enables robust colorimetric read-out for EV concentrations as low as 107 EVs/ml, achieved within a short incubation time of two minutes, while using a CCD camera or naked eye for the read-out. This approach offers the potential for rapid sensing without the need for spectrometers and provides a short response time. Our findings suggest that the synergy between optofluidics and metasurface platforms can enhance the detection efficiency of low concentration bioparticle samples by overcoming the diffusion limits.