High throughput spectroscopy of pL droplets

TL;DR

This paper introduces an integrated optofluidic platform combining droplet microfluidics and hyperspectral imaging for high-resolution, label-free analysis of single picolitre droplets, enabling rapid, sensitive, and long-term biosensing and nanoparticle studies.

Contribution

The authors develop a novel platform that merges droplet microfluidics with hyperspectral imaging, allowing detailed analysis of individual droplets with high temporal resolution and sensitivity.

Findings

Successfully studied dynamic nanoparticle changes with millisecond resolution

Achieved DNA detection sensitivity of approximately 100 pM

Enabled long-term multiplexed monitoring of samples

Abstract

Droplet microfluidics offers a versatile platform for analyzing liquid samples. Despite its potential, there is a lack of techniques that allow to reliably probe individual circulating droplets. The prospect of combining droplet microfluidics with sensitive, broadband spectroscopic techniques would therefore unlock new capabilities for various disciplines, including biomedicine and biochemistry. Here we present an integrated optofluidic platform that seamlessly combines droplet microfluidics and advanced hyperspectral imaging. This enables high-resolution, label-free analysis of single picolitre-sized droplets, providing valuable insights into their content. As a proof-of-principle, we demonstrate the ability of our platform to study rapid dynamic changes in a heterogeneous population of plasmonic nanoparticles with millisecond-time resolution. Furthermore, we demonstrate the effectiveness of the platform in biosensing applied to short DNA strands, achieving a detection sensitivity in the range of 100 pM. Finally, we show that the platform provides the flexibility to monitor samples over extended periods of time (hours) in a multiplexed manner.