High sensitive concentration analysis of biochemical liquids using a microfluidic chip fabricated by femtosecond laser

摘要

We demonstrate fabrication of microfluidic chips integrated with optical waveguide embedded in a photostmcturable glass for high-sensitive biochemical liquid analysis using a femtosecond laser. Femtosecond laser direct writing followed by annealing and successive wet etching in hydrofluoric acid solution resulted in the rapid manufacturing of microfluidic chips for the biochemical liquid concentration assay. By covering the internal wall of the microfluidic channel in the glass with low refractive index polymer, interaction between the liquid and incident analyzing light is enhanced. Therefore, the microfluidic chip enables us to analyze the low concentrations down to 7.5 mM of protein in bovine serum albumin. Such microfluidic chip realizes the efficient and high-sensitive concentration analysis of biochemical liquids at early stages of biochemical reactions.