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Point-of-care (POC) diagnostic devices have been predicted to provide a boon in health care especially in the diagnosis and detection of diseases. POC devices have been found to have many advantages like a rapid and precise response, portability, low cost, and non-requirement of specialized equipment. The major objective of a POC diagnostic research is to develop a chip-based, self-containing miniaturized device that can be used to examine different analytes in complex samples. Further, the integration of microfluidics (MF) with advanced biosensor technologies is likely to result in improved POC diagnostics. This paper presents the overview of the different materials (glass, silicon, polymer, paper) and techniques for the fabrication of MF based POC devices along with their wide range of biosensor applications. Besides this, the authors have presented in brief the challenges that MF is currently facing along with possible solutions that may result in the availability of the accessible, reliable, and cost-efficient technology. The development of these devices requires the combination of developed MF components into POC devices that are user-friendly, sensitive, stable, accurate, low cost, and minimally invasive. These MF based POC devices have tremendous potential in providing improved healthcare including easy monitoring, early detection of disease, and increased personalization., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

There is a strong interest in the use of biopolymers in the electronic and biomedical industries, mainly towards low-cost applications. The possibility of developing entirely new kinds of products based on cellulose is of current interest, in order to enhance and to add new functionalities to conventional paper-based products. We present our results towards the development of paper-based microfluidics for molecular diagnostic testing. Paper properties were evaluated and compared to nitrocellulose, the most commonly used material in lateral flow and other rapid tests. Focusing on the use of paper as a substrate for microfluidic applications, through an eco-friendly wax-printing technology, we present three main and distinct colorimetric approaches: (i) enzymatic reactions (glucose detection); (ii) immunoassays (antibodies anti-Leishmania detection); (iii) nucleic acid sequence identification (Mycobacterium tuberculosis complex detection). Colorimetric glucose quantification was achieved through enzymatic reactions performed within specific zones of the paper-based device. The colouration achieved increased with growing glucose concentration and was highly homogeneous, covering all the surface of the paper reaction zones in a 3D sensor format. These devices showed a major advantage when compared to the 2D lateral flow glucose sensors, where some carryover of the coloured products usually occurs. The detection of anti-Leishmania antibodies in canine sera was conceptually achieved using a paper-based 96-well enzyme-linked immunosorbent assay format. However, optimization is still needed for this test, regarding the efficiency of the immobilization of antigens on the cellulose fibres. The detection of Mycobacterium tuberculosis nucleic acids integrated with a non-cross-linking gold nanoprobe detection scheme was also achieved in a wax-printed 384-well paper-based microplate, by the hybridization with a species-specific probe. The obtained results with the above-mentioned proof-of-concept sensors are thus promising towards the future development of simple and cost-effective paper-based diagnostic devices.