Azure II is widely used in biological and medical research as a staining agent. It is particularly valuable in histology and cytology for enhancing the visibility of cellular structures under a microscope. The stain helps differentiate various tissue components, making it easier to study cell morphology and identify abnormalities. Azure II is often employed in combination with other dyes to achieve optimal contrast and clarity in tissue samples. Its application is crucial in diagnosing diseases, conducting research on cellular processes, and advancing understanding in fields like pathology and microbiology.