Fabrication and Fluorescence Analysis of Rhodamine Dyes in Polycarbonate Serpentine Microfluidic System

Abstract

This work investigates the emission of polycarbonate substrates (PC) by UV-visible. Erotic nano-stage and 193 nm laser ablation are used to measure the ablation threshold (16mj.sec-1) of PC at 193nm wavelength after that ablation process continued to produce microfluidic serpentine channels on PC by using G-Code. The fluorescence characteristics of Rhodamine 6G and Rhodamine 101 are investigated. To conduct a more quantitative analysis of the absorption and emission spectrum, plot the integrated signal strength of absorption and emission at the peak wavelength against the concentrations of R6G and R101. Furthermore, the refractive indices of both R6G and R1010 vis concentrations are investigated; at low concentrations, there was overlapping, and at high concentrations, there was the least amount of overlapping. We observed that the two dyes differed greatly from one another; R101 showed better photostability and a more consistent diffusion, whereas R6G had a faster diffusion and stronger fluorescence intensity. These differences were caused by the different molecular structures of the dyes and their interactions with the PC micro-channel. The present research illustrates the varied behaviors of two fluorescent dyes in such environments and highlights the importance of precise microfabrication techniques in the development of microfluidic devices. This article presents experimental results for two dyes, R6G and R101. These are standard dyes with high Quantum Yields (QY), QY efficiencies depend on several factors one of which includes solvent concentrations, which are typically 97% and 100% respectively. These dyes will be used as standards when we measure QY for other non-standard materials. Other dyes are currently being synthesized within the chemistry department at the University of Hull. The dyes will be integrated on-board the LOC systems in reservoirs and cavities suitably positioned on the substrate architecture. Routing light around the small foot-print of LOC devices and spatially controlling how the light is confined to a waveguide is highly important in this work.