Low-cost fluorescence microscope with microfluidic device fabrication for optofluidic applications

TL;DR

This paper presents a low-cost, DIY fluorescence microscope integrated with microfluidic device fabrication, enabling optofluidic experiments such as laser-induced cavitation and flow analysis with minimal equipment and cost.

Contribution

It provides a comprehensive guide for building a customizable, affordable fluorescence microscope and microfluidic devices for optofluidic research.

Findings

Successful construction of a low-cost fluorescence microscope

Demonstration of laser-induced cavitation inside microchannels

Application of PIV technique for fluid flow analysis

Abstract

Optofluidic devices have revolutionized the manipulation and transportation of fluid at smaller length scales ranging from micrometers to millimeters. We describe a dedicated optical setup for studying laser-induced cavitation inside a microchannel. In a typical experiment, we use a tightly focused laser beam to locally evaporate the solution laced with a dye resulting in the formation of a microbubble. The evolving bubble interface is tracked using high-speed microscopy and digital image analysis. Furthermore, we extend this system to analyze fluid flow through fluorescence$-$Particle Image Velocimetry (PIV) technique with minimal adaptations. In addition, we demonstrate the protocols for the in-house fabrication of a microchannel tailored to function as a sample holder in this optical setup. In essence, we present a complete guide for constructing a fluorescence microscope from scratch using standard optical components with flexibility in the design and at a lower cost compared to its commercial analogues.