A novel handheld fluorescent microarray reader for point-of-care diagnostic

• PortMD-113 was built from only a few lightweight, small and low-cost components.
• Its capabilities were tested under point-of-care (low-energy) model conditions.
• The measurement results were compared to that of a modern benchtop laser scanner.
• The agreement of measurement results of the two devices was found to be R2=0.995.
• The detection limit of our handheld sensor is close to that of top microarray readers.

A novel handheld optical sensor for quantification of fluorescent microarrays, the so-called portMD-113 has been developed. On the surface of a planar waveguide, the spots of different fluorescently labeled biological complexes are excited by the evanescent field of the guided light. The emitted fluorescence signals of the spots are independently and simultaneously detected applying our system, which consists of a pinehole array, a microlens array, an interference filter and a detector array. As it is demonstrated in comparative measurements, the detection limit of this sensor is close to that of commercial top microarray readers, e.g. of modern laser scanners, while it has remarkable and important advantages over them. Namely, the device comprises only a few low-cost, lightweight and small components without applying any moving or energy-intensive elements, which results in turn in a commercially competitive, handheld and compact design and in the possibility to be supplied simply by a battery or a personal computer. These advantageous properties open prospects e.g. for point-of-care medical checks, as well.