Medical Applications of ColloidsThe important role of ? nely dispersed matter and surfaces in medicine is not always fully understood and appreciated. Speci? cally, ? ne particles (solid or liquid) in the size range of several nanometers to several micrometers have a tremendous effect on our lives, because they can be bene? cial or detrimental to our well being. Such particles are present in living bodies as red blood cells or cholesterol crystals in the gall bladder. They are