Functionalized Carbon Nanomaterials as Building Blocks for the Development of Affinity Biosensors

Visegrád

Conferencia; Mátrafüred 2022-International Conference on Chemical Sensors; 2022

This communication is focused on the design, characterization and analytical applications of nanobiosensors based on the use of rationally functionalized carbon nanotubes and graphenaceousmaterials. Special attention was given to the influence of nanostructures functionalization andbiorecognition/transduction events on the analytical performance of the resulting nanoarchitecturesfor the quantification of cancer and Covid-19 biomarkers.The electrochemical (bio)sensors were obtained by modification of glassy carbon, screen printedcarbon and gold electrodes modified with multiwalled carbon nanotubes (MWCNTs) noncovalently functionalized with (bio)molecules or graphenaceous materials modified withpolymers as platforms to allow the selective anchoring of the biorecognition molecules or todirectly work as biorecognition elements..We propose a new strategy to build impedimetric genosensors connected to the use of MWCNTsdispersed in avidin as platform to support the DNA probes in a mode analogue to the magneticnanobeads. The resulting architectures were used for the non-label and non-amplifiedquantification of BRCA1 and SARS-CoV-2 RNA at femtomolar and atomolar levels, respectively.We also propose the development of highly sensitive and selective impedimetric and plasmonicmicroRNA-21 nanobiosensors based on the use of graphenaceous materials modified withchitosan as platform to immobilize the DNA probe.The results demonstrated that the rational design of the bioanalytical platforms through the criticalselection of the nanomaterial functionalization, biorecognition event and transduction scheme arekey aspects for the development of highly sensitive and selective sequence-specific detectionbiosensors. The proposed schemes not only represent a model for further design of biosensinglayers and bioaffinity biosensors, but also for the development of novel in-situ amplificationschemes.