Multicolor Single-Molecule Spectroscopy with Alternating Laser Excitation for the Investigation of Interactions and Dynamics

2007 ◽  
Vol 111 (2) ◽  
pp. 321-326 ◽  
Author(s):  
Joachim Ross ◽  
Peter Buschkamp ◽  
Daniel Fetting ◽  
Achim Donnermeyer ◽  
Christian M. Roth ◽  
...  
2015 ◽  
Vol 17 (41) ◽  
pp. 27862-27872 ◽  
Author(s):  
Shazia Farooq ◽  
Johannes Hohlbein

Here the authors report on significant improvements in time-resolution and throughput in camera-based single-molecule detection by combining stroboscopic alternating-laser excitation with dynamic probability distribution analysis.


2014 ◽  
Vol 43 (4) ◽  
pp. 1156-1171 ◽  
Author(s):  
Johannes Hohlbein ◽  
Timothy D. Craggs ◽  
Thorben Cordes

2008 ◽  
Vol 36 (4) ◽  
pp. 738-744 ◽  
Author(s):  
Yusdi Santoso ◽  
Ling Chin Hwang ◽  
Ludovic Le Reste ◽  
Achillefs N. Kapanidis

Single-molecule fluorescence methods, particularly single-molecule FRET (fluorescence resonance energy transfer), have provided novel insights into the structure, interactions and dynamics of biological systems. ALEX (alternating-laser excitation) spectroscopy is a new method that extends single-molecule FRET by providing simultaneous information about structure and stoichiometry; this new information allows the detection of interactions in the absence of FRET and extends the dynamic range of distance measurements that are accessible through FRET. In the present article, we discuss combinations of ALEX with confocal microscopy for studying in-solution and in-gel molecules; we also discuss combining ALEX with TIRF (total internal reflection fluorescence) for studying surface-immobilized molecules. We also highlight applications of ALEX to the study of protein–nucleic acid interactions.


2012 ◽  
Vol 58 (4) ◽  
pp. 707-716 ◽  
Author(s):  
Seok W Yim ◽  
Taiho Kim ◽  
Ted A Laurence ◽  
Steve Partono ◽  
Dongsik Kim ◽  
...  

Abstract BACKGROUND Single-molecule detection (SMD) technologies are well suited for clinical diagnostic applications by offering the prospect of minimizing precious patient sample requirements while maximizing clinical information content. Not yet available, however, is a universal SMD-based platform technology that permits multiplexed detection of both nucleic acid and protein targets and that is suitable for automation and integration into the clinical laboratory work flow. METHODS We have used a sensitive, specific, quantitative, and cost-effective homogeneous SMD method that has high single-well multiplexing potential and uses alternating-laser excitation (ALEX) fluorescence-aided molecule sorting extended to 4 colors (4c-ALEX). Recognition molecules are tagged with different-color fluorescence dyes, and coincident confocal detection of ≥2 colors constitutes a positive target-detection event. The virtual exclusion of the majority of sources of background noise eliminates washing steps. Sorting molecules with multidimensional probe stoichiometries (S) and single-molecule fluorescence resonance energy transfer efficiencies (E) allows differentiation of numerous targets simultaneously. RESULTS We show detection, differentiation, and quantification—in a single well—of (a) 25 different fluorescently labeled DNAs; (b) 8 bacterial genetic markers, including 3 antibiotic drug–resistance determinants found in 11 septicemia-causing Staphylococcus and Enterococcus strains; and (c) 6 tumor markers present in blood. CONCLUSIONS The results demonstrate assay utility for clinical molecular diagnostic applications by means of multiplexed detection of nucleic acids and proteins and suggest potential uses for early diagnosis of cancer and infectious and other diseases, as well as for personalized medicine. Future integration of additional technology components to minimize preanalytical sample manipulation while maximizing throughput should allow development of a user-friendly (“sample in, answer out”) point-of-care platform for next-generation medical diagnostic tests that offer considerable savings in costs and patient sample.


2015 ◽  
Vol 2015 (11) ◽  
pp. pdb.top086405 ◽  
Author(s):  
Achillefs Kapanidis ◽  
Devdoot Majumdar ◽  
Mike Heilemann ◽  
Eyal Nir ◽  
Shimon Weiss

Sign in / Sign up

Export Citation Format

Share Document