Universal Bioanalyte Signal Amplification for Electrochemical Biosensor

A rapid, simple, and inexpensive electrochemical biosensor with guanine-conjugated microbead tags can achieve the detection limits of PCR and culturing. Guanine is a redox species that functions as an electrochemical tag for bioanalyte detection. Microbeads conjugated with guanine-rich oligonucleotides deliver millions of electrochemical tags per bioanalyte. When guanine-conjugated microbeads are used in a sandwich assay with magnetic beads and matched ligand pairs, extremely low levels of diverse bioanalytes can be electrochemically measured including microorganisms, proteins and nucleic acids.