IMMUNOANALYTICAL SYSTEMS FOR HEPATITIS A VIRUS DETERMINATION

Hepatitis A virus (HAV) causes an acute hepatitis associated with a significant morbidity and occasional mortality. Outbreaks of waterborne diseases are certainly underestimated due to the lack of adequate programs for the epidemiological surveillance. Current legislation for water, shellfish (EC 2073/2005 EC B53/2004) and plant (EC 2073/2005) does not provide for any limitation due to the presence of HAV and other enteric viruses in the irrigation and housing waters. In addition, there is no official method for the detection of these viruses. The diagnosis is based on the patient's symptoms and more specifically through the search for anti-HAV IgM and/or anti-HAV IgG antibodies in blood. Immunoanalytical approaches are reported as methods to determine HAV in drinking water before its use, thus avoiding the infectious disease. In this work, two electrochemical, competitive and sandwich, Enzyme Linked ImmunoMagnEtic assays (ELIME) are showed. These systems are based on the use of new polydopamine-modified magnetic nanobeads as solid support for the immunochemical chain, and screen printed electrodes as a sensing platform. This rapid and low-cost analysis method involves the use of a portable instrument, able to perform measurements directly in the field. These ELIME assays showed detection limits equal to 1•10-8 IU/mL and 8 10-7 IU/mL for sandwich and competitive formats, respectively. The proposed systems were applied to drinking water. Results obtained on real samples were compared with those obtained by the qRT-PCR analysis that is a routine technique used to evaluate the HAV contamination levels in samples