How To Avoid Oxidation Of Vitamin C Serum
To avoid oxidation of Vitamin C serum (which makes it turn brown and less effective), follow these tips:
1. Choose the Right Packaging
- Pick serums in dark, opaque, or amber glass bottles to protect from light.
- Use containers with air-tight pumps or droppers to minimize air exposure.
2. Store Properly
- Keep your serum in a cool, dark place, ideally in the refrigerator.
- Avoid leaving it near heat sources or in direct sunlight.
3. Use Small Amounts and Avoid Contamination
- Use a clean fingertip or dropper to avoid introducing bacteria.
- Don’t leave the bottle open longer than necessary.
4. Check the Formula
- Look for serums with stable Vitamin C derivatives like magnesium ascorbyl phosphate or sodium ascorbyl phosphate—they oxidize slower than pure L-ascorbic acid.
- Formulas with added antioxidants like vitamin E or ferulic acid increase stability.
5. Replace Regularly
- Vitamin C serums have a limited shelf life (3-6 months after opening).
- Discard if the serum changes color (turns brown, orange, or dark yellow) or smells off.