Chen J, Tsai A, Petrov A, Puglisi JD. Nonfluorescent quenchers to correlate single-molecule conformational and compositional dynamics. J Am Chem Soc. 2012 Apr 4;134(13):5734-7. doi: 10.1021/ja2119964. Epub 2012 Mar 23. PMID: 22428667.