Why Proper Reconstitution Matters
Reconstitution is the process of dissolving lyophilized (freeze-dried) peptides into a liquid solution. Proper technique is crucial for:
- Maintaining peptide integrity - Ensuring accurate research results - Preventing bacterial contamination - Maximizing peptide stability
What You'll Need
Required Materials: - Lyophilized peptide vial - Bacteriostatic water (BAC water) - preferred - Sterile syringes with needles - Alcohol swabs - Clean workspace
Why Bacteriostatic Water?
Bacteriostatic water contains 0.9% benzyl alcohol, which: - Prevents bacterial growth - Allows for multiple uses from the same vial - Extends the shelf life of reconstituted peptides
**Note:** Sterile water can also be used but must be used immediately as it doesn't contain preservatives.
Step-by-Step Reconstitution
Step 1: Prepare Your Workspace - Work in a clean, well-lit area - Wash hands thoroughly - Gather all materials
Step 2: Calculate Your Volume Use this formula:
``` Peptide amount (mg) ร 1000 = Total mcg Total mcg รท Desired concentration (mcg/ml) = Volume of water (ml) ```
**Example:** 10mg peptide, wanting 500mcg/0.1ml concentration: - 10mg ร 1000 = 10,000 mcg - 10,000 รท 5,000 = 2ml of BAC water
Step 3: Sterilize Everything - Wipe the rubber stopper of both vials with alcohol swabs - Let dry for 30 seconds
Step 4: Add Solvent Carefully 1. Draw the calculated amount of BAC water into your syringe 2. Insert needle through the rubber stopper 3. **CRITICAL:** Aim the stream at the SIDE of the vial, not directly on the powder 4. Release slowly, letting water run down the glass wall
Step 5: Let It Dissolve - Do NOT shake the vial - Gently swirl or rotate - Let sit for a few minutes if needed - The solution should become clear
Step 6: Store Properly - Place in refrigerator (2-8ยฐC) - Keep away from light - Use within 14-30 days (varies by peptide)
Common Mistakes to Avoid
โ **Spraying water directly on the powder** - This can denature the peptide
โ **Shaking vigorously** - Can cause protein denaturation
โ **Using too little water** - Creates an overly concentrated solution
โ **Freezing reconstituted peptides** - Never freeze; it destroys the structure
โ **Contaminating the stopper** - Always sterilize before inserting needle
Storage Guidelines
| State | Temperature | Duration | |-------|-------------|----------| | Lyophilized | -20ยฐC | 24+ months | | Lyophilized | 2-8ยฐC | 3-6 months | | Reconstituted | 2-8ยฐC | 14-30 days | | Reconstituted | Room temp | NOT recommended |
Troubleshooting
Solution is cloudy - May indicate contamination or degradation - Do not use; start with a new vial
Powder won't dissolve - Let sit longer (up to 30 minutes) - Gently swirl periodically - Try slight warming (room temperature only)
White particles visible - Could be undissolved peptide or contamination - Gently swirl again - If persists, do not use
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*For research purposes only. Follow your institution's guidelines and protocols.*