Hematoxylin is widely used in histology and pathology for staining tissues. It binds to cell nuclei, providing a blue or purple color that helps distinguish cellular structures under a microscope. This staining is essential for diagnosing diseases, as it highlights nuclei, chromatin, and other components in tissue samples. It is often paired with eosin (H&E staining) to provide contrast, allowing for detailed examination of tissue morphology. Hematoxylin is particularly valuable in cancer research and diagnosis, enabling the identification of abnormal cell growth and tissue changes. Its application is a cornerstone in medical laboratories for preparing tissue samples for microscopic analysis.