Light source comparison: indoors and outdoors.

<p>(A) The KS-Detect system during an experiment using sunlight. Lens must be manually aligned with the sun as the sun moves across the sky. (B) For experiments conducted indoors, the lens and microfluidics are removed from our portable kit, and are fixed in front of a 100 Watt LED array. (C) A typical solar temperature profile is more variable when compared to a typical LED array temperature profile, due to cloud coverage (as seen at about 35 min.) and intermittent realignment of the lens with the sun.</p

The KS-Detect system.

<p>(A) The system contains all components necessary for solar thermal PCR and subsequent analysis, including reagents, tablet, and solar panel. The focusing lens is fixed to the red container on a hinge, allowing rotation (blue arrow) for alignment with the sun. (B) The system is easily carried in one hand, affording easy transportation to patients in remote communities. (C) Microfluidics schematic. Samples are cycled between the warmer center of a PDMS chip (for denaturation of DNA) and the cooler edges (for annealing of primers). A thin, black PDMS layer (not pictured) serves as the bottom of the microfluidic chip, and absorbs solar radiation. (D) Our custom Android application is used to track each temperature zone within the microfluidics and to (E) analyze results via fluorescence levels imaged by a smartphone or tablet.</p

Visual comparison of pseudo-biopsy and human biopsy samples.

<p>Cell block pseudo-biopsies with varying KS-positive cells (bottom) were used to imitate human biopsies (top) to validate function of the device. Cell block pseudo-biopsies were embedded in paraffin and stained for latency-associated nuclear antigen (LANA) for comparison with LANA stained human biopsies. KSHV-infected nuclei are brown with dark punctae, while uninfected nuclei are blue. Images of human biopsies were taken from representative sections of KS-positive samples with concentrations similar to the cell block biopsies by visual inspection. The 0% image was taken from an uninfected region of a human sample with low concentration of KS positive cells. Precise analysis of infected cell percentage per sample was performed using HALO image analysis software (Indica Labs), and can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0147636#pone.0147636.s002" target="_blank">S1</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0147636#pone.0147636.s006" target="_blank">S5</a> Figs. Scale bar applies to all images.</p