Protein Detection Using Three-Dimensional Carbon Microarrays

摘要

The potential of aptamers as ligand binding molecule have opened new avenues in the development of biosensors for proteins, such as cancer oncoproteins. Disclosed herein is a label-free detection strategy using signaling aptamer/protein binding complex for proteins, such as platelet-derived growth factor (PDGF-BB) oncoprotein. The detection mechanism is based on the release of a fluorophore (e.g., TOTO intercalating dye) from the target binding aptamer's stem structure when it captures the protein, e.g., PDGF. Amino-terminated three-dimensional carbon microarrays fabricated by pyrolyzing patterned photoresist are used as a detection platform. The sensor showed near linear relationship between the relative fluorescence difference and protein concentration even in the sub-nanomolar range with an excellent detection limit of 5 pmol. This detection strategy is promising in a wide range of applications in the detection of cancer biomarkers and other proteins.