The colloidal iron solution (working solution) according to Müller is an essential aid in histology and medical diagnostics. It is used in particular for staining mucins and acidic polysaccharides found in certain tissues and cells. Its special suitability lies in its affinity for these substances, giving reliable and accurate results.

The solution consists of colloidal iron in the form of ferric chloride dissolved in water, and acetic acid. These components interact to create a colloidal system that triggers a staining reaction upon contact with certain biological materials.

The way it works is based on the interaction of the colloidal iron with the acidic groups in mucins and polysaccharides. This interaction results in a visible staining that can be observed under a microscope. In biomedical research and diagnostics, this solution is used, for example, in the examination of digestive tract tissues, the diagnosis of cancer or the analysis of cell cultures. The Müller colloidal iron solution is a proven instrument that provides reliable and repeatable results.