Hydroquinone 2 % is a central component of staining kits such as the GENTA staining kit for Helicobacter pylori and the STEINER silver plating kit according to CHAPMAN. It is suitable for use in in vitro diagnostics. The chemical structure is based on hydroquinone, also known as 1,4-dihydroxybenzene, dissolved in pure water. Due to its specific chemical properties - especially its ability to act as a reducing agent - hydroquinone plays a crucial role in these staining kits. Application of the solution results in the development of distinct, readily differentiable colors that enable precise identification of specific microorganisms such as Helicobacter pylori. In addition, hydroquinone helps to highlight the structure of materials in materialography.