1.2.2 Peripheral Blood Film
A blood film is a thin layer of blood smeared on a microscope slide that contains the blood cells to be examined (Figure 1.16). Blood films are commonly examined to investigate haematological problems. A blood film is prepared by placing a drop of blood on one end of a slide, and using a spreader slide to disperse the blood over the slide's length. The aim is to make sure that cells are spaced far enough apart to be counted and differentiated. The slide is left to air dry, after which the blood is fixed to the slide by immersing it briefly in methanol [3]