A cost-effective Z-folding controlled liquid handling microfluidic paper analysis device for pathogen detection via ATP quantification

A cost-effective microfluidic paper analysis device (mu PAD) was developed with a special Z-folding design for controlling the fluidic flowing and substrate transportation. This presented mu PAD can be easily fabricated through wax printing by using a solid ink printer which deposits wax onto the surface of a chromatographic paper, and then baked on a hotplate by penetrating the molten wax into the paper to create a hydrophobic barrier. After mu PAD fabrication, liquid control and substrate transportation can be easily carried out by twice folding the mu PAD following Z shape. The Z folding made two separated reagent holding zone connected while the detection reaction occurred with the connection. In this paper, a pathogens detection indicated by ATP quantification was took as a proof-in-principle application of using this presented mu PAD, the limit of detection (LOD) was 1 mu M for ATP detection and 2.6 x 10(7) CFU/mL for Salmonella live cell detection, which showed a great potential for Point-of-Care Testing (POCT) applications. (C) 2014 Elsevier B.V. All rights reserved.