Nanostructured Aptamer-Functionalized Black Phosphorus Sensing Platform for Label-Free Detection of Myoglobin, a Cardiovascular Disease Biomarker

We report the electrochemical detection of the redox active cardiac biomarker myoglobin (Mb) using aptamer-functionalized black phosphorus nanostructured electrodes by measuring direct electron transfer. The as synthesized few-layer black phosphorus nanosheets have been functionalized with poly-L-lysine (PLL) to facilitate binding with generated anti-Mb DNA aptamers on nanostructured electrodes. This aptasensor platform has a record-low detection limit (similar to 0.524 pg mL(-1)) and sensitivity (36 mu A pg(-1) mL cm(-2)) toward Mb with a dynamic response range from 1 pg mL(-1) to 16 mu g mL(-1) for Mb in serum samples. This strategy opens up avenues to bedside technologies for multiplexed diagnosis of cardiovascular diseases in complex human samples.