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arXiv · 2302.00062

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

Nagaraj Nagalingam·Aswin Raghunathan·Vikram Korede·Edwin F. J. Overmars·Shih-Te Hung·Remco Hartkamp·Johan T. Padding·Carlas S. Smith·Huseyin Burak Eral
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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.

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Nagaraj Nagalingam, Aswin Raghunathan, Vikram Korede, Edwin F. J. Overmars, Shih-Te Hung, Remco Hartkamp, Johan T. Padding, Carlas S. Smith, Huseyin Burak Eral. 2023-03-01. Low-cost fluorescence microscope with microfluidic device fabrication for optofluidic applications. https://doi.org/10.1016/j.ohx.2023.e00415

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