Imunosensor label-free para detecção eletroquímica de Síndrome Pulmonar por Hantavírus

Hantavirus are viruses classified in the family Bunyaviridae, which infects rodents and bats, and can lead to two severe illness in humans based on the variation of the virus: Hemorrhagic fever with renal syndrome (HFRS) and Hantavirus Pulmonary Syndrome (HPS). The focus of this work: Hantavirus of the genotype araucaria, leads to HPS, and as the firsts symptoms are very influenzalike, after a period of 2 to 7 days it evolves to respiratory failure and hemodynamic instability. Currently, the HPS detection can be performed by Enzyme-linked immunosorbent assay (ELISA) and it can take several hours due to long incubation time required in each step.[1] As alternative, such drawback can be reduced by electrochemical detection, allowing quick measurements with lower both limit of detection and reagent consuming. The modification of gold disc surface (working electrode) was performed using 11- Mercaptoundecanoic acid (MUA) to form Self-Assembled Monolayers and EDC/NHS reactions to bind the biomolecules to the modified gold surface.[2] Electrochemical Impedance Spectroscopy is a powerful technique used to characterize surfacemodified electrodes for the investigation of electrochemical system and processes.[3] According to Figure 1, it was found that the Nyquist semicircles at higher frequencies increased as the layers were added to the gold surface. It indicates the increasing of the charge transfer resistance at the electrode/electrolyte interface may be caused by the additional layer which acts as a kinetic barrier to the process, assuring the interaction between the biomolecules pair. The selectivity of the interaction was tested using a control antigen and a control antibody, aided by bovine serum albumin to block nonspecific interaction sites.