Highly sensitive detection of human cancer antigens by an immunogold-silver assay chip coupled with a polythiophene-based optical sensor.

This work presents a novel method for protein or cancer antigen detection in clinical samples by an immunogold-silver assay microfluidic biochip coupled with a polythiophene-based organic photodetector. The method has showed a detection limit below 1ng/mL and the low cost and high sensitivity of both organic photodetector and immunogold-silver assay make this method amenable for realization in a portable handheld probe tip biosensor.