What is progressive staining characterized by?

Progressive staining is characterized by the ability to achieve the exact correct amount of staining by allowing the specimen to be stained for a specific duration. This method relies on the principle that specimens are immersed in a staining solution until they reach the desired intensity of color, depending on the type of tissue and the staining protocol used. The key to progressive staining is that it does not rely on a predetermined amount of time for staining but rather the visual assessment of color under a microscope, ensuring optimal results for the specific tissue being stained.

While longer staining times might sometimes be necessary, the defining feature of progressive staining is the precise timing needed to achieve the desired staining outcome without over-staining. This distinguishes it from other methods where overstaining can lead to obscured details or inconsistent results. The goal of progressive staining is to create clear, distinguishable features in the specimen, which is not achieved when staining is uniform or consistent throughout the slide, as that can mask important structural information.