Abstract: Described herein are three-dimensional (3-D) paper fluidic devices. The entire 3-D device is fabricated on a support layer formed from a single sheet of material and assembled by folding the support layer. The folded structure may be enclosed in an impermeable cover or package. Chemically sensitive particles may be disposed in the support layer for use in detecting analytes.

Abstract: Methods and devices electrochemically detect analytes. The methods employ metal particles conjugated to the analytes. The metal particles can serve as an electrochemical label for the analyte to which they are conjugated. The metal particles can be oxidized to form metal ions that can subsequently be electrochemically detected and/or quantified. The metal ions can be electrodeposited as metal on a working electrode. The potential applied at the working electrode can then be varied to reoxidize the deposited metal to metal ions. The intensity of the resulting voltammetric peak reflects the amount of metal deposited on the working electrode, and therefore the amount of metal nanoparticle label and analyte. Sensitivity can tie improved by selectively localizing the analyte-metal particle conjugate in the vicinity of the working electrode. Analytes can be detected at concentrations as low as 767 fM via anodic stripping voltammetry, with no washing steps or electrode modifications.

Abstract: Described herein are three-dimensional (3-D) paper fluidic devices. The entire 3-D device is fabricated on a support layer formed from a single sheet of material and assembled by folding the support layer. The folded structure may be enclosed in an impermeable cover or package. Chemically sensitive particles may be disposed in the support layer for use in detecting analytes.