What is the first step in preparing a peripheral blood smear?

The first step in preparing a peripheral blood smear involves spreading a drop of blood onto a glass slide. This step is crucial as it creates a thin, even layer of blood cells that allows for optimal visualization under a microscope. By ensuring the blood is well spread, the technician can adequately examine the morphology of the individual cells, which is vital for diagnosing various hematological conditions.

To prepare the smear, typically a small drop of blood is placed on one end of a clean glass slide, and another slide is used to spread the blood across the surface by making contact with the drop at a 30 to 45-degree angle. This technique is key in achieving a sufficient thickness for examination, enabling the detection of abnormalities in cell shape, size, and distribution.

The other options involve steps in the process but are not the initial actions. Preparing a fixed slide happens after the smear is created and involves techniques that preserve the cellular structure for staining and analysis. Using a centrifuge is more related to processing blood samples for specific tests rather than surface smear preparation. Staining with methanol is involved in fixing the cells after they have been smeared, not in the initial preparation.