A microfluidic nanostructured fluorescence sensor for biomolecular binding detection

This paper reports a new fluorescence sensor with integrated micropatterned anodized aluminum oxide (AAO) inside a microfluidic device for immunoassay for the first time. The micropatterned AAO serves as an enhancer for fluorescent signals. The binding between Protein A and rabbit immunoglobulin G (IgG) labeled by fluorescent dye FITC is used as a model for the immunoassay. Experiments show the sensor can detect rabbit IgG at concentration of ~13 nM without any device optimization using a conventional fluorescence microscope. Given the simple and inexpensive fabrication process of the micropatterned AAO inside a microfluidic chip, a highly sensitive and disposable microfluidic fluorescence sensor can be developed for a variety of fluorescence related applications.