Animal-side diagnosis using a paper-based microfluidic device

One of the most promising technologies that have recently been applied within point-of-care (POC) diagnostics is microfluidics. At present, two main types of microfluidic systems are used: micro total analysis systems (µTAS) and microfluidic paper-based analytical devices (µPADs). The latter ones, in particular, are very appealing for low resource settings, due to their low-cost and ease of fabrication. Within the field of µPADs, a very interesting application is the translation of ELISA onto paper or P-ELISA. P-ELISA combines the sensitivity and specificity of ELISA with the intrinsic low cost and ease-of-use of paper-based platforms. In veterinary diagnostics, POC tests or “animal-side” tests will have enormous advantages over lab based testing: more affordable veterinary care, reduced animal handling, targeted and rapid treatments and availability of testing in more remote areas, with overall improvements in animal health and welfare. Within veterinary diagnostics, the use of haptoglobin (Hp) as a marker of disease status has recently attracted considerable attention. Hp is a serum biomarker, an acute phase proteins which increase rapidly following infection or inflammation, providing a quantification of the tissue. This presentation will focus on a new fabrication method for realisation of a multi-pad paper plate (mp3), which can be used to translate virtually any ELISA assay into a P-ELISA. The functionality of the multi-pad paper plate was applied to the optimisation of a sandwich ELISA assay, where a standard curve was generated based on the data obtained by the P-ELISA assay. The optimised protocol was further tested by analysing bovine serum samples with different Hp concentration and by comparing results with the existing laboratory-based ELISA.