Neutron and ion beams in biological research

On the scattering length density of proteins in H2O/D2O: Determination of H-D exchange using ES+I-MS
  • W. G. Bouwman


Neutron reflectometry is an excellent technique to determine the structure of a protein layer adsorbed at a solid interface. The use of contrast-variation makes it possible to highlight the adsorbed protein layer. The neutron scattering lengths of D and H have opposite signs. By choosing the H2O/D2O ratio, the scattering length density can be made equal to that of the adsorbing substrate. To determine the scattering length density of protein, both its volume and its scattering length in solution is needed. To calculate the scattering length, the H-D exchange of the labile protons of the protein should be taken into account. For monitoring the H-D exchange, electrospray ionization mass spectroscopy (ES+I-MS) was applied. We show that ES+I-MS is the appropriate technique for quantitative analysis of the H-D exchange. We compare the experimental results for the exchange in lysozyme and &bgr;-casein with theoretical calculations.


Lysozyme Scattering Length Adsorb Substrate Scatter Length Density Scattering Length Density 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag/Akadémiai Kiadó 2005

Authors and Affiliations

  • W. G. Bouwman

    There are no affiliations available

    Personalised recommendations