Stainig method that cannot differentiate between bacteria.
Loffler methylene blue solution: methylene blue crystals 1 g, phenol crystals
melted, 96% alcohol 10 ml, distilled water 100 ml.
Dry and heat fix the slide, then cover it with methylene blue solution
Wait 2 to 5 minutes then rinse in distilled water and dry the slide.
Vegetative forms of bacteria appear blue colored.
Using old, oxidized, Loffler methylene blue solution (stored over few months) capsule will be pink-colored and the
rest of the cell will be blue.
1. H. Raducanescu, V. Bica-Popii,1986. Bacteriologie veterinara, Ed. Ceres, Bucuresti.
2. Dumitru Buiuc, Carmen Panzaru: Coloratii, coloranti si reactivi pentru microscopie, micrometrie. In Dumitru Buiuc,
Marian Negut: Tratat de microbiologie clinica ed. III, 2009, 1173-1215.
(c) Costin Stoica