DSS (NMR Standard)

Chembox new
ImageFile = DSS.png ImageSize = 200px
IUPACName = 2,2-Dimethyl-2-silapentane-5-sulfonic acid
OtherNames =
Abbreviations= DSS
Section1 = Chembox Identifiers
CASNo=18173-90-5
CASOther =
CASREF|CAS=2039-96-5 (sodium salt)
PubChem =
SMILES = C [Si] (C)(C)CCCS(=O)(=O)O
Section2 = Chembox Properties
C=6|H=16|O=3|S=1|Si=1
MolarMass = 218.325
Appearance = White solid
Density =
MeltingPt =
BoilingPtC = 120
Solubility = Miscible
Section3 = Chembox Hazards
MainHazards =
FlashPt =
Autoignition =

DSS is a chemical compound used in proton- and carbon-related NMR spectroscopy as a calibration standard, similar to tetramethylsilane (TMS), but with much higher water solubility. Whereas TMS is the most common NMR standard used in organic solvents such as chloroform or benzene, DSS or its sodium salt is more often used for protein experiments in water.

The low electronegativity of the silicon shields the nine identical methyl protons. The result is a high intensity proton signal further upfield (at lower chemical shift) than almost all peaks found in naturally occurring organic molecules. The resulting standard peak is easily identified as such and set to chemical shift 0.0.

The proton spectrum of DSS also exhibits minor peaks at 3.1 ppm (triplet), 1.9 ppm (pentet), and 0,8 ppm (triplet) at an intensity of 22% of the reference peak at 0 ppm. These peaks appear much smaller in height than the reference singlet because of their width. If these peaks pose a problem, a deuterated version of DSS is available at much higher cost.