What is the shelf life of Acetonitrile?

When stored properly in tightly sealed containers away from heat and direct sunlight, Acetonitrile maintains its quality for at least 24 months from production date. Our recommended storage temperature is between 15°C and 25°C in well-ventilated areas.

Is Acetonitrile compatible with all HPLC systems?

While Acetonitrile is commonly used in HPLC applications, compatibility depends on specific system components. Most modern HPLC systems with PEEK, stainless steel, or titanium components work well with Acetonitrile. However, we recommend checking with your equipment manufacturer regarding any plastic components that might degrade with prolonged exposure.

What safety precautions should be taken when handling Acetonitrile?

Acetonitrile requires proper ventilation (fume hood recommended), chemical-resistant gloves (nitrile or neoprene), and safety goggles. The vapor is flammable and harmful if inhaled, so avoid open flames and ensure adequate ventilation. In case of skin contact, wash immediately with plenty of water for at least 15 minutes.

What is the difference between HPLC grade and industrial grade Acetonitrile?

HPLC grade Acetonitrile undergoes additional purification processes to achieve higher purity (≥99.9%) with lower UV absorbance and very low levels of impurities that could interfere with sensitive analytical methods. Industrial grade typically has purity ≥99% and may contain higher levels of water and other organic contaminants acceptable for non-analytical applications.

Can Acetonitrile be mixed with water for HPLC applications?

Yes, Acetonitrile is completely miscible with water across all proportions. For HPLC applications, we recommend using HPLC-grade water when preparing mobile phases. The mixture produces less heat compared to methanol-water mixtures and offers different selectivity in reversed-phase chromatography.

How should Acetonitrile waste be disposed?

Acetonitrile waste should never be poured down drains. Collect in approved chemical waste containers labeled for halogenated solvents. Small quantities can be evaporated in a fume hood (with proper permits), but most jurisdictions require disposal through licensed hazardous waste handlers due to its toxicity and flammability.

What are the alternatives to Acetonitrile in HPLC applications?

Methanol is the most common alternative to Acetonitrile in HPLC, though it provides different selectivity and retention characteristics. Other options include ethanol, isopropanol, or acetone, but these may require method redevelopment and validation. The choice depends on analyte properties and detection requirements.

Why does Acetonitrile sometimes show baseline noise in HPLC?

Baseline noise with Acetonitrile can result from several factors: impurities from production or degradation, improper storage leading to moisture absorption, or interactions with system components. Using fresh, high-purity Acetonitrile from reliable suppliers and proper mobile phase degassing typically resolves these issues.

How does Acetonitrile compare to methanol as an extraction solvent?

Acetonitrile generally provides cleaner extracts with less co-extraction of non-polar interferences compared to methanol. It's particularly effective for polar compounds and is the preferred solvent for QuEChERS methods. However, methanol may be better for more lipophilic compounds and is typically less expensive.