زایلن هیستولوژی

Xylene (Histological Grade) is a colorless, sweet‑smelling aromatic hydrocarbon mixture composed mainly of ortho‑, meta‑, and para‑xylene isomers (plus small amounts of ethylbenzene). It serves as the gold‑standard clearing agent in histology due to its excellent solvency for paraffin and compatibility with mounting media.

🏭⚗️ Production
Xylene used in histological applications typically comprises a mixture of ortho‑, meta‑, and para‑xylene isomers, along with ethylbenzene and minor impurities. This specific blend enhances its hydrophobic properties, making it highly effective for clearing processes in tissue preparation.

🔬 Properties
Histological‑grade xylene is a clear, colorless liquid with a molecular formula of C₈H₁₀ and a molar mass around 106.17 g/mol. Its boiling point ranges between 136–145 °C, melting point around –25 °C, density approximately 0.86–0.87 g/cm³, and vapor pressure near 8–10 hPa at 20 °C.

🧪 Applications
In histology, xylene is most widely used as a clearing agent. After dehydration of tissue specimens through alcohol, xylene removes residual alcohol and makes tissues transparent, enabling effective paraffin infiltration. It is also used after staining to clear slides before coverslipping, ensuring proper mounting. These properties are critical in both manual and automated histological workflows.

⚠️ Safety
Xylene is highly flammable and poses significant health risks if not handled properly. It may be harmful if swallowed, inhaled, or upon skin contact, causing irritation and systemic effects. Inhalation at high concentrations can depress the central nervous system, leading to symptoms such as headache, dizziness, nausea, and impaired reaction time. Prolonged or frequent exposure may lead to more serious chronic effects.