Disposable microfluidic sensor arrays for discrimination of antioxidants

A microfluidic colorimetric sensor array was developed for detection and identification of various antioxidants. The sensor was fabricated by a photolithographic method, and consists of an array of printed cross-responsive indicators. The microfluidic design also incorporates pre-activation spots to allow printing of chemically incompatible components separately. Separately printed oxidizer allowed an oxidation of adjacent redox indicators only when aqueous sample was added to the sensor cartridge. Antioxidants were primarily detected by measuring the extent of inhibition of this oxidation reaction. Using this flow-based technique, a clear differentiation of 8 different antioxidants and 4 different teas has been demonstrated with 98.5% sensitivity. [Display omitted] •A microfluidic colorimetric array was developed for identification of antioxidants.•Mechanism of detection relies on pre-activating oxidizer spot printed onto channel.•Method expands compound characterization via redox potential.•Sensor can be used for single analytes or complex mixtures of antioxidants.