Noirahaeng N.Uraisin K.Wattanasin P.Saetear P.Mahidol University2023-06-182023-06-182022-03-01Analytical Sciences Vol.38 No.3 (2022) , 533-54009106340https://repository.li.mahidol.ac.th/handle/20.500.14594/84202In this work, we present for the first time, a simplified fabrication of a laminated paper-based analytical device (LPAD) with a free-mobile app, Palette Cam, for image analysis. A filter paper is cut in a rectangular shape (9 × 3 cm) and placed between a top laminating sheet with punched holes and a bottom laminating sheet. The holes allow accessibility of liquid on the paper. Thermal lamination is then employed to complete the fabrication of LPAD. Our simplified design reduces a tedious alignment of small pieces of paper to the holes. We demonstrated the LPAD with an analysis of salicylic acid in pharmaceutical products. Each 4 μL of ferric reagent and sample was dispensed on the LPAD. Smartphone was used to capture images. The RGB (red green blue) color intensity from the Palette Cam was converted into a logarithm color ratio. Our LPAD is simplified, cost-effective and able to be a portable device. Graphical abstract: [Figure not available: see fulltext.]ChemistryArticleSCOPUS10.2116/analsci.21P2312-s2.0-851274086291348224635359271