Single-molecule detection on a portable 3D-printed microscope

• Published in: Nature communications Vol. 10; no. 1; pp. 5662 - 7
• Main Authors: Brown, James W. P., Bauer, Arnaud, Polinkovsky, Mark E, Bhumkar, Akshay, Hunter, Dominic J. B., Gaus, Katharina, Sierecki, Emma, Gambin, Yann
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11.12.2019; Nature Publishing Group; Nature Portfolio
• Subjects: 631/337/470/2284; 631/337/470/460; 631/57/2265; 706/648/160; Fluorescence; Fluorescence spectroscopy; Humanities and Social Sciences; Microscopes; multidisciplinary; Science; Science (multidisciplinary); Synuclein; Three dimensional printing
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-13617-0

Single-molecule assays have, by definition, the ultimate sensitivity and represent the next frontier in biological analysis and diagnostics. However, many of these powerful technologies require dedicated laboratories and trained personnel and have therefore remained research tools for specialists. Here, we present a single-molecule confocal system built from a 3D-printed scaffold, resulting in a compact, plug and play device called the AttoBright. This device performs single photon counting and fluorescence correlation spectroscopy (FCS) in a simple format and is widely applicable to the detection of single fluorophores, proteins, liposomes or bacteria. The power of single-molecule detection is demonstrated by detecting single α-synuclein amyloid fibrils, that are currently evaluated as biomarkers for Parkinson’s disease, with an improved sensitivity of >100,000-fold over bulk measurements. Single-molecule in vitro assays require dedicated confocal microscopes equipped with fluorescence correlation spectroscopy (FCS) modules. Here the authors present a compact, cheap and open-source 3D-printed confocal microscope for single photon counting and FCS measurements, and use it to detect α-synuclein aggregation.