Abstract: The present disclosure relates methods of chromogen layering, wherein a first chromogen and a first stain (color) are produced on a sample, specific for a first analyte, followed by a second chromogen and a second stain (color) being produced on the same sample, specific for a second analyte. In addition, if desired, by overlaying the second stain on top of the first stain, a unique third color is produced that is specific for a third analyte. Therefore, the distribution of different colors throughout the sample could be used to identify at least two or more analytes simultaneously within a single sample.

Abstract: The present disclosure relates to counterstains for staining a biological sample on a single slide in preparation for microscopic examination. The counterstains are used to analyze the sample on the single slide using both brightfield and fluorescent illumination. The counterstains can identify both morphological details and molecular structures within the cells contained in the sample. The counterstains can be used in conjunction with other molecular stains.

Abstract: The present disclosure relates to an aqueous sealing fluid for sealing a stained biological specimen present on a microscope slide for microscopic analysis. The sealing fluid protects the biological specimen from drying artifacts, protects stains performed on biological specimen from fading, and protects stains performed on biological specimens from being dissolved by organic mounting media. Methods of using the aqueous sealing fluid are also disclosed.