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

LÓPEZ MUJICA, MICHAEL; TAMBORELLI, LUIS A.; GALLAY, PABLO A.; VASCHETTI, VIRGINIA M.; PERRACHIONE, FABRIZIO; REARTES, DAIANA F.; DELPINO, ROCÍO; RODRÍGUEZ, MARCELA C.; RUBIANES, MARÍA D.; DALMASSO, PABLO R.; RIVAS, GUSTAVO A.

Congreso; 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 graphenaceous materials. Special attention was given to the influence of nanostructures functionalization and biorecognition/transduction events on the analytical performance of the resulting nanoarchitectures for the quantification of cancer and Covid-19 biomarkers.The electrochemical (bio)sensors were obtained by modification of glassy carbon, screen printed carbon and gold electrodes modified with multiwalled carbon nanotubes (MWCNTs) non-covalently functionalized with (bio)molecules or graphenaceous materials modified with polymers as platforms to allow the selective anchoring of the biorecognition molecules or to directly work as biorecognition elements.. We propose a new strategy to build impedimetric genosensors connected to the use of MWCNTs dispersed in avidin as platform to support the DNA probes in a mode analogue to the magnetic nanobeads. The resulting architectures were used for the non-label and non-amplified quantification 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 plasmonic microRNA-21 nanobiosensors based on the use of graphenaceous materials modified with chitosan as platform to immobilize the DNA probe. The results demonstrated that the rational design of the bioanalytical platforms through the critical selection of the nanomaterial functionalization, biorecognition event and transduction scheme are key aspects for the development of highly sensitive and selective sequence-specific detection biosensors. The proposed schemes not only represent a model for further design of biosensing layers and bioaffinity biosensors, but also for the development of novel in-situ amplification schemes.