On-chip graphene oxide aptasensor for multiple protein detection.

The versatility of an on-chip graphene oxide (GO) aptasensor was successfully confirmed by the detection of three different proteins, namely, thrombin (TB), prostate specific antigen (PSA), and hemagglutinin (HA), simply by changing the aptamers but with the sensor composition remaining the same. The results indicate that both DNA and RNA aptamers immobilized on the GO surface are sufficiently active to realize an on-chip aptasensor. Molecular selectivity and concentration dependence were investigated in relation to TB and PSA detection by using a dual, triple, and quintuple microchannel configuration.

Molecular design for enhanced sensitivity of a FRET aptasensor built on the graphene oxide surface.

We designed a biomolecular probe for highly sensitive protein detection by modifying an aptamer with a DNA spacer. The spacer controls the distance between a fluorescence dye and a quencher, which is crucial for FRET-based sensors. We successfully demonstrated an improvement in the sensitivity of an on-chip graphene oxide aptasensor.