Miniaturized portable image-recording device for paper-based nucleotide assays with nanoparticles

This study describes the development of a portable image-recording device that is lightweight, inexpensive, and compatible with commercial smartphones and paper-based analytical devices. A light-unaffected environment is essential for optical quantification in colorimetric-based or fluorescence-based assays, and we have previously developed a portable fluorescent image-recording device. Here, we attempted to miniaturize the portable image-recording device by using a thin-film LED strip and minimize the cost of the device by using colored glassine as a light filter. Finally, we demonstrated the capacity to measure DNA-AuNPs concentration with a paper-based device.