Academic Talk: Capacitance Sensor for Label-free, Real-time Analysis of Circulating Cancer Biomarkers


Presenter: Dr. Pietro Capaldo (Institute of Materials(IOM), Italian National Research Council, Trieste (Italy)

Topic: Capacitance Sensor for Label-free, Real-time Analysis of Circulating Cancer Biomarkers

Time: 10:00AM, January 18th (Thursday)

Location: 910-308


The quantification of significant amounts of disease biomarkers circulating in the bloodstream represents one of the challenging frontiers in biomedicine. The complexity of blood composition has opened the quest for novel detection technologies, capable of discerning small amount of specific biomarkers from other blood proteins/oligonucleotides and of reliably measuring them.

In this context, we have developed a label-free device based on differential double-layer capacitance readout at microfabricated gold electrodes and demonstrated its detection performance in real biosample volumes.

By means of electrochemical impedance spectroscopy (EIS) measurements in a three electrodes setup, we first calibrated the system following the in situ hybridization of a self-assembled monolayer of single-stranded, short oligonucleotides on the gold microelectrode through the measurement of differential capacitance changes as a function of time, for different concentrations of complementary DNA in a saline buffer. Based on this calibration we used the device to quantify the presence of microRNAs (miRNAs) in human plasma. We demonstrated that our device is fast, sensitive, reusable, reproducible, and perfectly suited to detect biomarkers in complex matrices, as cell lysate, serum, and plasma.

We put forward the possibility to apply this platform to the bioaffinity detection of protein biomarkers as well as circulating drugs in blood, for therapeutic drug monitoring applications.



Dr. Pietro Capaldo is a research fellow at Institute of Materials(IOM), Italian National Research Council, Trieste (Italy). He received his PhD in Nanotechnology in University of Trieste. His Project was Capacitance immunosensors for the early detection of circulating cancer biomarkers, and his supervisor was Dr. Loredana Casalis. He was a Research Assiociate at Nanoinnovation Laboratory. There he focused on the development of miniaturized biosensors based on Electrochemical Impedence Spectroscopy for the detection of microRNAs and protein biomarkers relevant for cancer and heart failure diseases circulating in the body fluids. Now he works on 1) Design and realization of an optical biosensor based on array of plsmonic crystal for label free genomics detection and on the possibility of multiplexing detection by means of integrated photodetectors.2) Design, fabrication and characterization of Silicon Metasurfaces for nanophotonic devices using OAM beams as light decoders. 


Contact: Prof. Jian Chen


Editor: Juan Yang