title: Effects of arginine and other solution additives on the self-association of different surfactants: an investigation at single-molecule resolution.
abstract: Fluorescence correlation spectroscopy is used to monitor the self-association of SDS and DTAB monomers at single-molecule resolution. Tetramethylrhodamine-5-maleimide (TMR) has been chosen as a probe because rhodamine dyes have been shown to bind surfactant micelles. Correlation functions obtained by FCS experiments have been fit using conventional discrete diffusional component analysis as well as the more recent maximum entropy method (MEM). Hydrodynamic radii calculated from the diffusion time values increase with surfactant concentration as the monomers self-associate. Effects of several solution additives on the self-association property of the surfactants have been studied. Urea and glycerol inhibit self-association, and arginine shows a dual nature. With SDS, arginine favors self-association, and with DTAB, it inhibits micelle formation. We propose surfactant self-association to be a "supersimplified" model of protein aggregation.
authors.affiliation: Structural Biology and Bioinformatics Division, Indian Institute of Chemical Biology, Council of Scientific and Industrial Research, 4 Raja S. C. Mullick Road, Kolkata 700032, India.
authors.forename: Shubhasis
authors.initials: S
authors.lastname: Haldar
authors.forename: Krishnananda
authors.initials: K
authors.lastname: Chattopadhyay
mesh_terms: D001120:Arginine / Q000737:chemistry*; D005990:Glycerol / Q000737:chemistry; D006575:Heterocyclic Compounds, 3-Ring / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012235:Rhodamines / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012996:Solutions; D013050:Spectrometry, Fluorescence; D013501:Surface-Active Agents / Q000737:chemistry*; D014508:Urea / Q000737:chemistry
chemical_list: D006575:Heterocyclic Compounds, 3-Ring; D008823:Micelles; D000644:Quaternary Ammonium Compounds; D012235:Rhodamines; D012996:Solutions; D013501:Surface-Active Agents; C412715:tetramethylrosamine; C013912:decyltrimethylammonium; D012967:Sodium Dodecyl Sulfate; C005358:tetramethylrhodamine; D014508:Urea; D001120:Arginine; D005990:Glycerol