Development and construction of a point of care device for application to molecular diagnostics

Abstract

In recent years, Argentina and countries of the region, have suffered epidemics associated with arboviruses, mainly Dengue and more recently Zika and Chikungunya. On the other hand, since the worldwide pandemic of SARS-CoV-2 (COVID-19), people’s health and the economic support of their countries have been seriously affected. It is necessary to have economic and faster diagnostic tools that allows evaluating samples of patients with symptoms. With this objective, diagnostic systems called point of care have been recently developed. These systems are defined as medical diagnostic testing at or near the point of care (that is, at the time and place of patient care). Specifically, in this work, a bio-photonic device has been developed. This instrument is able to detect certain diseases by means of a luminescence spectral analysis. This method can be conducted for saliva samples. The system consists in the fluorescence signal detection generated by a specific probe of the target viral genome, that coupled to isothermal amplification reaction, allowing the detection of the pathogen in the sample. The device excites the sample to be analyzed with light (led or semiconductor lasers with specific wavelengths) thus it triggers a spontaneous emission of the fluorophore bound to the specific probe. The emitted fluorescence is suitably filtered using interferential filters. These filters limit the spectral regions and allow discriminating the analysis band. Under these conditions, a signal is registered in a built-in detector and, depending on the signal level, define the case as positive or negative. All the analysis is done autonomously inside the developed device through an integrated control system and it is connected to a portable device to show the results wirelessly.