Used as a biological stain in histology and cytology to differentiate cell structures, particularly in nuclear staining. Commonly applied in microscopic analysis to enhance contrast of cellular components. Also utilized as an acid-base indicator due to its pH-sensitive color change. In addition, it serves as a counterstain in some microbiological staining protocols to improve visualization of specimens. Furthermore, it is employed to stain DNA in agarose gel electrophoresis for direct visualization of DNA bands in molecular biology research.