WATER DYNAMICS IN BIOPOLYMER GELS BY QUASI-ELASTIC NEUTRON-SCATTERING

A new pulsed-source spectrometer has been used to measure quasi-elastic neutron scattering from agarose-H2O gels with high resolution in both energy and momentum. Line broadenings between 3 and 300 mueV were analysed to quantify the dynamic structuring of water contained by a random network of hydrophilic fibres as a function of polymer concentration (1-20%) and temperature (263-325 K). The results throw light on the nature of biological water, provide new benchmarks for molecular-dynamics simulations, and show that a distribution of proton jump distances can be obtained by direct Fourier inversion of experimental data.