A quantitative x-ray microanalytical comparison of intracellular ion concentrations in two tissues (chicken kidney and duck nasal salt gland), prepared as bulk frozen-hydrated, embedded freeze-dried and freeze-substituted samples, shows that there are similar losses of K+ and Pin freeze-dried and freeze-substituted samples in both types of tissue. It is suggested that this may be due to extraction by chloride-free Spurr's resin during infiltration. There was also an indication of an increase in Na+ concentration in freeze-dried samples.
In chicken kidney cells there was a reduction in Mg++ and Ca++ concentrations in freeze-dried and freeze-substituted samples and an increase in Cl- concentration in freeze-dried samples (which may have been partially due to contamination) and a decrease in freeze-substituted samples. In spite of these differences between kidney preparations, consistent differences in Na+ and Cl-concentrations between kidneys from normal chickens and chickens infected with IBV (infectious bronchitis virus) which causes perturbations in kidney physiology were observed in frozen-hydrated, freeze-dried and freeze-substituted preparations.
Condron, R. J. and Marshall, A. T.
"A Comparison of Three Low Temperature Techniques of Specimen Preparation for X-Ray Microanalysis,"
Scanning Microscopy: Vol. 4
, Article 23.
Available at: https://digitalcommons.usu.edu/microscopy/vol4/iss2/23