diciembre 2, 2020

Prof. Dr. Omar Azzaroni

( Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas INIFTA – CONICET)

Topic: Label-Free Sensors Based on Graphene Field-Effect Transistors for the Detection of Biomarkers.

Since the discovery and isolation of graphene from graphite in 2004, the two-dimensional material has shown potential to revolutionize many technological areas owing to its remarkable electrical, optical, mechanical and thermal properties. The extraordinary surface-to-volume ratio of graphene facilitates a high density of molecular recognition elements to be immobilized onto its surface. Within this framework, biosensors based on solution-gated graphene field-effect transistors (FETs) have gained much attention in clinical diagnosis because they are suitable for real-time, high-throughput and highly sensitive detections. However, to date, most of the research efforts in graphene-based FETs (gFETs) biosensors are based on the immobilization of biomolecules by covalent binding to functional groups of graphene or to a linker molecule. As already known, covalent attachment can disrupt the folding and functionality of the native biomolecule if essential groups are involved in the immobilization and, in addition, the formation of covalent bonds can induce damage to the sp2 structure of graphene.

In this presentation, we will describe new approaches towards the non-covalent construction of novel ultrasensitive enzymatic gFET biosensors employing “reactive signal amplifiers” as key elements coupled to the transduction mechanism. We will show that the integration of enzymatic
processes onto gFETs via electrostatic assembly confers them outstanding specificity on target analytes resulting from biological recognition, offers innovative design concepts to amplify the detected the bioelectronic signal and pushes the boundaries of interfacial sensitivity in graphene
FET sensors. Examples will be shown that a variety of biomarkers of clinical interest can be sensitively detected by rationally designing the interfacial (bio)architecture integrated on the graphene platform.

Summary Background

Omar Azzaroni studied chemistry at the Universidad Nacional de La Plata (UNLP) (Argentina), receiving his Ph.D. in 2004. His postdoctoral studies were carried out at the University of Cambridge (UK) (2004–2006, Marie Curie Research Fellow) and the Max Planck Institute for Polymer Research (Germany) (2007, Alexander von Humboldt Research Fellow). He was then appointed as Max Planck Partner Group leader from 2009 until 2013. He has served as Vice-Director of the Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) (2012-2015). He is currently a fellow member of CONICET and head of the Soft Matter Laboratory of INIFTA. Since 2009, he is also Adjunct Professor of Physical Chemistry at UNLP. His research interests include nanostructured hybrid interfaces, supra- and macromolecular materials science and soft nanotechnology. More information on his current activities can be found at: https://softmatter.quimica.unlp.edu.ar or https://www.facebook.com/SoftMatterLaboratory/.