Vietz, Carolin Schütte, Max L. Wei, Qingshan Richter, Lars Lalkens, Birka Aydogan Ozcan Tinnefeld, Philip Acuna, Guillermo P. 2019-01-31 Smartphone-based fluorescence microscopy has been rapidly developing over the last few years, enabling point-of-need detection of cells, bacteria, viruses, and biomarkers. These mobile microscopy devices are cost-effective, field-portable, and easy to use, and benefit from economies of scale. Recent developments in smartphone camera technology have improved their performance, getting closer to that of lab microscopes. Here, we report the use of DNA origami nanobeads with predefined numbers of fluorophores to quantify the sensitivity of a smartphone-based fluorescence microscope in terms of the minimum number of detectable molecules per diffraction-limited spot. With the brightness of a single dye molecule as a reference, we compare the performance of color and monochrome sensors embedded in state- of-the-art smartphones. Our results show that the monochrome sensor of a smartphone can achieve better sensitivity, with a detection limit of ∼10 fluorophores per spot. The use of DNA origami nanobeads to quantify the minimum number of detectable molecules of a sensor is broadly applicable to evaluate the sensitivity of various optical instruments. application/pdf https://folia.unifr.ch/global/documents/307800 https://folia.unifr.ch/documents/307800/files/acu_bsf.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1021/acsomega.8b03136 info:eu-repo/semantics/openAccess License undefined ACS Omega. - 2019, vol. 4, no. 1, p. 637–642 info:eu-repo/classification/udc/57 Benchmarking smartphone fluorescence-based microscopy with DNA origami nanobeads: reducing the gap toward single-molecule sensitivity http://purl.org/coar/resource_type/c_6501