Description
Lugol PVP Solution is an iodine-based mordant used in the Gram-staining procedure.
The formulation contains iodine, potassium iodide and polyvinylpyrrolidone. Applied after crystal violet, it forms a dye–iodine complex that is retained differently by Gram-positive and Gram-negative bacterial cells during the subsequent decolourisation step.
The solution is applied to a prepared bacterial smear according to the staining sequence in the PDF, followed by decolourisation, counterstaining and microscopic examination.
