The Gram-Color modified (phenol-free) - staining kit for Gram staining method on bacteriological smears, is used for human-medical cell diagnosis and serves the purpose of the bacteriological investigation of sample material of human origin from smears of body fluids. Gram-Color modified is a staining kit which is used for a modified Gram staining. The Gram-Color modified solutions are modified and designed in such a way that staining can be carried out on the staining rack. In bacteriology, the Gram staining allows a fast differentiation of bacteria in Gram-positive and Gram-negative. The mureine structure of the bacteria wall is the basis of the color affinity. In the first step, bacteria will be stained with crystal violet an aniline dye. After the treatment with iodine solution (Lugol′s solution), a dye-iodine complex will form. During the decolorizing step, this complex stays in the multilayer mureine structure of the cell wall of Gram-positive bacteria - they will appear blue-violet. Gram-negative bacteria, by contrast, have a cell wall consisting of a single-layered murein structure, and correspondingly re-release the staining dye with the decoloring solution. Gram-negative bacteria will be counterstained with fuchsin solution and will then appear red.