Description

Acetonitrile (chemical formula CH₃CN) is a colorless, volatile liquid with a faint, sweet odor. It is a simple nitrile compound and is highly polar, making it an effective solvent for a wide range of chemical reactions. Acetonitrile is commonly used in laboratories as a solvent for organic reactions, particularly in chromatography, and for protein precipitation. It is miscible with water, alcohols, and many other organic solvents.

Common Uses in a Biology Lab

• Solvent in Chromatography: Acetonitrile is widely used as a solvent in high-performance liquid chromatography (HPLC) and other chromatographic techniques. Its low viscosity and high solvent strength make it ideal for separating various compounds in complex biological samples.
• Protein Precipitation: Acetonitrile is commonly used to precipitate proteins from biological samples. This is important in protein purification and isolation, especially when removing contaminants or concentrating proteins.
• DNA/RNA Extraction: In molecular biology, acetonitrile is sometimes used in DNA or RNA extraction protocols, particularly in the precipitation step, where it helps to remove impurities and concentrate the nucleic acids.
• Solvent for Organic Reactions: Acetonitrile serves as a solvent in various organic reactions, particularly for synthesizing compounds used in pharmaceutical research and biochemistry.
• Solvent for Electrophoresis Buffers: It is occasionally used in the preparation of electrophoresis buffers, where it helps in the separation of nucleic acids and proteins based on their size and charge.

Safety Hazards

• Toxicity: Acetonitrile is toxic if ingested, inhaled, or absorbed through the skin. Inhalation of vapors can cause headache, dizziness, nausea, and more severe symptoms like respiratory distress and central nervous system depression.
• Flammability: Acetonitrile is highly flammable and should be kept away from heat sources, sparks, and open flames. It can form explosive mixtures with air at certain concentrations.
• Skin and Eye Irritation: Direct contact with acetonitrile can cause skin irritation and may lead to defatting or dermatitis with prolonged exposure. It can also irritate the eyes, causing redness and discomfort.
• Chronic Exposure: Prolonged exposure to acetonitrile vapors or liquid can cause more severe health effects, including liver or kidney damage, as well as adverse effects on the nervous system.
• Environmental Hazard: Acetonitrile is toxic to aquatic life and should be handled and disposed of carefully to prevent environmental contamination.

Handling

• PPE: Wear appropriate personal protective equipment, such as gloves, safety goggles, and a lab coat when handling acetonitrile. In areas where splashing is a risk, use a face shield.
• Ventilation: Use acetonitrile in a well-ventilated area or under a fume hood to avoid inhaling vapors. Adequate ventilation is essential, particularly when handling larger quantities or when heating the solvent.
• Storage: Store acetonitrile in a tightly sealed container in a cool, dry, well-ventilated area, away from heat, flames, and direct sunlight. It should be stored in a designated solvent storage area, away from incompatible chemicals.
• Disposal: Dispose of acetonitrile according to local hazardous waste disposal regulations. It should not be disposed of in the drain or general waste. Residues should be collected in properly labeled waste containers for safe disposal.