Journal of Biomolecular NMR

, Volume 71, Issue 2, pp 79–89 | Cite as

Concentration-dependent changes to diffusion and chemical shift of internal standard molecules in aqueous and micellar solutions

  • Benjamin Morash
  • Muzaddid Sarker
  • Jan K. RaineyEmail author


Sodium 4,4-dimethyl-4-silapentane-1-sulfonate (DSS) is the most widely accepted internal standard for protein NMR studies in aqueous conditions. Since its introduction as a reference standard, however, concerns have been raised surrounding its propensity to interact with biological molecules through electrostatic and hydrophobic interactions. While DSS has been shown to interact with certain proteins, membrane protein studies by solution-state NMR require use of membrane mimetics such as detergent micelles and, to date, no study has explicitly examined the potential for interaction between membrane mimetics and DSS. Consistent with its amphipathic character, we show DSS to self-associate at elevated concentrations using pulsed field gradient-based diffusion NMR measurements. More critically, DSS diffusion is significantly attenuated in the presence of either like-charged sodium dodecyl sulfate or zwitterionic dodecylphosphocholine micelles, the two most commonly used detergent-based membrane mimetic systems used in solution-state NMR. Binding to oppositely charged dodecyltrimethylammonium bromide micelles is also highly favourable. DSS-micelle interactions are accompanied by a systematic, concentration- and binding propensity-dependent change in the chemical shift of the DSS reference signal by up to 60 ppb. The alternative reference compound 4,4-dimethyl-4-silapentane-1-ammonium trifluoroacetate (DSA) exhibits highly similar behaviour, with reversal of the relative magnitude of chemical shift perturbation and proportion bound in comparison to DSS. Both DSS and DSA, thus, interact with micelles, and self-assemble at high concentration. Chemical shift perturbation of and modulation of micellar properties by these molecules has clear implications for their use as reference standards.


Internal chemical shift standard Aqueous detergent micelle solutions Solution-state NMR spectroscopy Membrane-mimetic environments 



Thanks to Dr. Mike Lumsden for spectrometer maintenance and troubleshooting support at Dalhousie’s Nuclear Magnetic Resonance Research Resource (NMR3), Bruce Stewart for technical assistance in the lab, and Dr. James Nowick (University of California, Irvine) for generously providing DSA. This work was funded by a Canadian Institutes of Health Research (CIHR) Operating Grant (MOP-111138 to J.K.R.) and a Nova Scotia Health Research Foundation (NSHRF) Scotia Support Grant (MED-SSG-2015-10041 to J.K.R.) J.K.R. was supported by a CIHR New Investigator Award.


  1. Alum MF, Shaw PA, Sweatman BC, Ubhi BK, Haselden JN, Connor SC (2008) 4,4-Dimethyl-4-silapentane-1-ammonium trifluoroacetate (DSA), a promising universal internal standard for NMR-based metabolic profiling studies of biofluids, including blood plasma and serum. Metabolomics 4:122–127CrossRefGoogle Scholar
  2. Bakshi MS, Sachar S, Mahajan N, Kaur I, Kaur G, Singh N, Sehgal P, Doe H (2002) Mixed-micelle formation by strongly interacting surfactant binary mixtures: effect of head-group modification. Colloid Polym Sci 280:990–1000CrossRefGoogle Scholar
  3. Calhoun AR, King AD (2007) The solubility of ethane in aqueous solutions of sodium 1-pentanesulfonate, sodium 1-hexanesulfonate, sodium 1-heptanesulfonate, and sodium 1-octanesulfonate at 25 °C. J Colloid Interface Sci 309:505–510CrossRefADSGoogle Scholar
  4. Cornilescu G, Delaglio F, Bax A (1999) Protein backbone angle restraints from searching a database for chemical shift and sequence homology. J Biomol NMR 13:289–302CrossRefGoogle Scholar
  5. De Marco A (1977) pH dependence of internal references. J Magn Reson 26:527–528ADSGoogle Scholar
  6. Jalali-Heravi M, Konouz E (2000) Prediction of critical micelle concentration of some anionic surfactants using multiple regression techniques: a quantitative structure-activity relationship study. J Surfactants Deterg 3:47–52CrossRefGoogle Scholar
  7. Khakbaz P, Klauda JB (2015) Probing the importance of lipid diversity in cell membranes via molecular simulation. Chem Phys Lipids 192:12–22CrossRefGoogle Scholar
  8. Lam Y-F, Kotowycz G (1977) Caution concerning the use of sodium 2,2-dimethyl-2-silapentane-5-sulfonate (DSS) as a reference for proton NMR chemical shift studies. FEBS Lett 78:181–183CrossRefGoogle Scholar
  9. Laurents DV, Gorman PM, Guo M, Rico M, Chakrabartty A, Bruix M (2005) Alzheimer’s Aβ40 studied by NMR at low pH reveals that sodium 4,4-dimethyl-4-silapentane-1-sulfonate (DSS) binds and promotes beta-ball oligomerization. J Biol Chem 280:3675–3685CrossRefGoogle Scholar
  10. Li Z-Z, Guo Q-X, Ren T, Zhu X-Q, Liu Y-C (1993) Can TMS and DSS be used as NMR references for cyclodextrin species in aqueous solution? J Incl Phenom Mol Recognit Chem 15:37–42CrossRefGoogle Scholar
  11. Markley JL, Bax A, Arata Y, Hilbers CW, Kaptein R, Sykes BD, Wright PE, Wuthrich K (1998) Recommendations for the presentation of NMR structures of proteins and nucleic acids. J Mol Biol 280:933–952CrossRefGoogle Scholar
  12. Misselyn-Bauduin AM, Thibaut A, Grandjean J, Broze G, Jerome R (2000) Mixed micelles of anionic-nonionic and anionic-zwitterionic surfactants analyzed by pulsed field gradient NMR. Langmuir 16:4430–4435CrossRefGoogle Scholar
  13. Morris KF, Johnson CS (1992) Diffusion-ordered 2-dimensional nuclear magnetic resonance spectroscopy. J Am Chem Soc 114:3139–3141CrossRefGoogle Scholar
  14. Mukerjee P, Mysels KJ (1971) Critical micelle concentrations of aqueous surfactant systems, National Standard Reference Data Series, vol 36. National Bureau of Standards, Washington, DCGoogle Scholar
  15. Nowick JS, Khakshoor O, Hashemzadeh M, Brower JO (2003) DSA: a new internal standard for NMR studies in aqueous solution. Org Lett 5:3511–3513CrossRefGoogle Scholar
  16. Opella SJ (2013) Structure determination of membrane proteins by nuclear magnetic resonance spectroscopy. Annu Rev Anal Chem 6:305–328CrossRefGoogle Scholar
  17. Pandey A, Shin K, Patterson RE, Liu XQ, Rainey JK (2016) Current strategies for protein production and purification enabling membrane protein structural biology. Biochem Cell Biol 94:507–527CrossRefGoogle Scholar
  18. Shimizu A, Ikeguchi M, Sugai S (1994) Appropriateness of DSS and TSP as internal references for 1H NMR studies of molten globule proteins in aqueous media. J Biomol NMR 4:859–862CrossRefGoogle Scholar
  19. Stejskal EO, Tanner JE (1965) Spin diffusion measurements: spin echoes in the presence of a time-dependent field gradient. J Chem Phys 42:288–292CrossRefADSGoogle Scholar
  20. Tremblay ML, Banks AW, Rainey JK (2010) The predictive accuracy of secondary chemical shifts is more affected by protein secondary structure than solvent environment. J Biomol NMR 46:257–270CrossRefGoogle Scholar
  21. Wishart DS, Sykes BD (1994) The 13C chemical-shift index: a simple method for the identification of protein secondary structure using 13C chemical-shift data. J Biomol NMR 4:171–180CrossRefGoogle Scholar
  22. Wishart DS, Sykes BD, Richards FM (1992) The chemical shift index: a fast and simple method for the assignment of protein secondary structure through NMR spectroscopy. Biochemistry 31:1647–1651CrossRefGoogle Scholar
  23. Wishart DS, Bigam CG, Yao J, Abildgaard F, Dyson HJ, Oldfield E, Markley JL, Sykes BD (1995) 1H, 13C and 15N chemical shift referencing in biomolecular NMR. J Biomol NMR 6:135–140CrossRefGoogle Scholar
  24. Wu DH, Chen AD, Johnson CS (1995) An improved diffusion-ordered spectroscopy experiment incorporating bipolar-gradient pulses. J Magn Reson A 115:260–264CrossRefADSGoogle Scholar

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© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Department of Biochemistry & Molecular BiologyDalhousie UniversityHalifaxCanada
  2. 2.Department of ChemistryDalhousie UniversityHalifaxCanada

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