A Multi-step Immunoassay Using Dry, Patterned Reagents in a Two-dimensional Paper Network Format

Here we demonstrate a multistep immunoassay using the controlled release of reagents patterned on a single porous membrane. Reagents are patterned, dried, and stored on-device for later rehydration, which removes the need for a cold chain and reduces user steps through the on-strip combination of signal enhancement reagents. The limit of detection for the malaria antigen Plasmodium falciparum histidine-rich protein 2 (PfHRP2) achieved using these devices is comparable to ELISA. This work demonstrates the viability of patterning and drying reagents directly onto a paper device for dry reagent storage and subsequent controlled release in paper-based assays.