Biological tissues (other than biominerals) exhibit poor contrast in X-ray imaging owing to their relatively homogenous composition and low X-ray attenuation. While staining is commonplace in the fields of optical and electron imaging, its application in biological X-ray imaging is only now emerging as a valuable method for non-destructive 3D imaging to document the external and internal anatomy of animals and plants.
Heavy metal stains that work well for electron microscopy are also applicable to X-ray micro-CT. Examples include iodine, phosphotungstic acid and osmium tetroxide. Iodine is a clear stain of choice for many applications as it penetrates deeply, is fast and relatively non-toxic. However, factors such as the penetration rate, staining time, tissue shrinkage and the affinity of iodine for certain tissue types, are poorly characterised. With a focus on iodine, this problem solver session will provide some general guidance to staining biology for X-ray micro-CT.
Dr Jeremy Shaw
Dr Shaw is platform leader for X-ray CT imaging at UWA's Centre for Microscopy, Characterisation and Analysis. A marine biologist by training, Dr Shaw's interests focus on the application of X-ray and electron microscope techniques to study structure and function in biominerals (teeth, bone, shell), but is more broadly interested the application of microscopy for the study of all biological, geological and synthetic materials.