Development of a colorimetric kit using gold nanoparticles for the diagnosis of canine parvovirus 2

Abstract

Canine parvovirus disease is an acute infectious disease caused by canine parvovirus 2 (CPV-2), a single-stranded DNA virus with no viral envelope and with the genome that does not encode the DNA polymerase enzyme. It has tropism for tissues with high cell replication, like the intestinal epithelium, embryonic tissues, lymphoids and bone marrow. There are currently three antigenic types: CPV-2a, CPV-2b and emerging in the early 2000's, CPV-2c. The main route is by direct oronasal contact, but indirect transmission may occur by contact with objects, mechanical vectors and contaminated environment. Fecal viral excretion occurs around four days before the onset of symptoms, and may continue for weeks after clinical improvement, and is an important mechanism of environmental contamination. Endemic in Brazil, the development of inexpensive, practical and fast techniques is necessary, since only clinical diagnosis is not trustworthy. Biosensors have been highlighted in the technological area as an analytical tool that can identify the presence of pathogens (antigens or nucleic acid) using nanoparticles as a base. The objective of this project is to develop and standardize colorimetric kits for the identification of CPV-2 in stool samples using modified gold nanoparticles with the deposition of antibodies or specific probes, which, when bound to their respective target will provide an immediate change of color. This is a new technique that will promote a fast laboratory diagnosis, simply and at low cost compared to usual methodologies. (AU)