A simple and rapid fluorescent neuraminidase enzymatic assay on a microfluidic chip

Neuraminidase enzymatic assay is an inexpensive, reliable, and quick method of detecting viruses. However, the assay in conventional laboratories requires a large amount of samples and reagents and multiple steps, which makes the conventional assay labor intensive and time consuming. This article reports a novel and simple method for conducting the neuraminidase enzymatic assay on a microfluidic chip. By using 4-methylumbelliferyl-N-acetyl-α-d-neuraminic acid as the fluorescent substrate and applying an electric field, the newly developed assay is simple, fast, and automatic. Fluorescence of the enzymatic reaction product was recorded as the assay result, and the fluorescence intensity quantitatively indicates the concentration of the sample, which proves that the novel assay on a microfluidic chip has a potential to be developed into a portable device for on-site detection of environmental samples.