Microfabricated needle for hydrogen peroxide detection.

A microfabricated needle-like probe has been designed and applied for hydrogen peroxide (HO) sampling and detection using a commercial, single-step fluorescent HO assay. In this work, droplets of the assay reagent are generated and sent to the needle tip using a mineral-oil carrier fluid. At the needle tip, the sample is drawn into the device through 100 μm long hydrophilic capillaries by negative pressure.