Storage precautions for L-valine

Storage precautions for L-valine

I. Environmental Condition Control

Temperature and Humidity Management

Store L-valine in a cool, dry place at 10–30°C. Avoid high temperatures (over 40°C may accelerate amino acid decomposition) or low-temperature freezing (crystal structure damage from freeze-thaw cycles). For long-term storage, use 2–8°C refrigeration, but prevent repeated freeze-thaw.

Maintain relative humidity ≤60%. L-valine is hygroscopic, and 潮湿 (humid) environments can cause powder caking or deliquescence, affecting purity. Place silica desiccant in storage containers and replace regularly.

Light and Air Isolation

Although L-valine has low photosensitivity, long-term exposure to strong light (especially UV) may trigger oxidation or optical isomerization. Store in brown containers or light-shielding packaging.

Seal containers to isolate oxygen and prevent amino group oxidation (oxidation rate accelerates under high temperature/humidity). Use inert gas (e.g., nitrogen) protection if necessary.

II. Packaging and Container Requirements

Material Selection

Use food-grade/pharmaceutical-grade sealed containers (glass bottles, polyethylene plastic bottles). Avoid direct contact with metals (iron, copper) to prevent metal ion-catalyzed degradation. For industrial-grade materials, use paper bags or barrels lined with polyethylene film, ensuring no packaging damage.

Subpackaging Principle

Divide large packages into small portions to reduce opening times. Seal immediately after each use to prevent moisture/dust ingress. For high-purity laboratory samples, use vacuum packaging or small vials protected by inert gas.

III. Chemical Stability and Risk Prevention

Acidity-Alkalinity and Chemical Compatibility

L-valine is prone to hydrolysis under strong acid/alkali conditions. Avoid mixing with strong acids (e.g., hydrochloric acid) or bases (e.g., sodium hydroxide), and maintain a neutral storage environment. Keep away from oxidants (e.g., hydrogen peroxide) or reductants (e.g., sulfides) to prevent chemical reactions.

For food/medical applications, ensure the storage area is free of toxic/hazardous substances (e.g., pesticides, chemical reagents) to avoid cross-contamination.

Microbial Contamination Prevention

For use in biological culture media or food additives, maintain a clean storage environment. Pre-sterilize containers (UV irradiation or moist heat sterilization /hydrothermal sterilization) and add trace preservatives (complying with relevant standards) if necessary to prevent microbial growth and spoilage.

IV. Safety and Labeling Management

Clear Labeling

Label containers with compound name, purity, batch number, production date, storage conditions, and expiration date to avoid confusion. For food/pharmaceutical grades, additionally mark compliance with quality standards (USP, EP, Chinese Pharmacopoeia, etc.).

Compliant Storage

Non-hazardous materials require no special management but should follow laboratory/industrial chemical storage regulations. Keep away from fire sources, flammable/explosive substances, and prevent access by children/unauthorized personnel.

V. Pre-Use Inspection and Handling

Observe the appearance before use. Obvious discoloration (yellowing, blackening), unusual odor, or caking may indicate deterioration. Test purity by IR spectroscopy, HPLC, etc., before use.

When removing from refrigeration, equilibrate at room temperature until no condensation forms on the container surface before opening to prevent sample deliquescence from moisture condensation.

Controlling storage temperature/humidity, packaging tightness, and chemical compatibility effectively maintains L-valine stability, extends shelf life, and ensures application efficacy in food, pharmaceutical, or chemical fields.