Cotton blue-lactophenol

Cotton blue-lactophenol, also known as Lactophenol Cotton Blue (LPCB), is a staining and mounting solution for microscopic identification of fungi, where cotton blue (aniline blue or methyl blue) stains fungal cell walls blue, while lactophenol preserves structures.​

Composition (Typical 100 mL Preparation)

Cotton blue (aniline blue): 0.05–0.125 g.​

Phenol crystals: 20–25 g (disinfectant).​

Lactic acid: 20–50 mL (preservative).​

Glycerol: 40–100 mL (mountant).​

Distilled water: 20–50 mL.​

Preparation Protocol

Dissolve cotton blue in distilled water; let stand overnight to settle insoluble dye.​

Dissolve phenol crystals in lactic acid (use gloves); add glycerol and stir.​

Filter the blue solution into the phenol mixture; mix and store at room temperature (matures 1–2 days).​

Properties and Uses

Appearance: Clear blue solution.​

Staining: Fungal hyphae, spores, and structures stain deep blue against pale blue background.​

Applications: Wet mounts for fungal microscopy in mycology; kills, preserves, and stains in one step.​

Handling

Light-stable but phenol-toxic; store sealed at RT. Use PPE; for lab use only.​

For catalog: “Cotton blue-lactophenol (LPCB), blue fungal stain/mountant, phenol-lactic acid-glycerol-aniline blue, for hyphae/spore microscopy; deep blue stain.”​