
Why Reconstitution Matters
Peptides are sold lyophilized (freeze-dried) for stability. They're a powder in a vial. Before use, you need to add bacteriostatic water to reconstitute them into an injectable solution.
Get this wrong and you could:
- Destroy the peptide (protein denaturation)
- Create a solution that's too concentrated or diluted
- Introduce contamination
- Cause unnecessary injection pain
Get it right and you have a stable, properly dosed solution ready for research.
What You'll Need
Essential Supplies
-
Bacteriostatic Water (BAC water)
- NOT sterile water (no preservative)
- NOT saline (can denature some peptides)
- Contains 0.9% benzyl alcohol (preservative)
- Allows multi-use over 28 days
-
Syringes
- Mixing: 1-3mL syringe for adding BAC water
- Injection: Insulin syringes (29-31 gauge, 1/2" needles)
- Never reuse needles
-
Alcohol Swabs
- For cleaning vial tops
- For injection site prep
-
The Peptide Vial
- Check the dosage amount (usually on label)
- Common amounts: 2mg, 5mg, 10mg
Optional but Recommended
- Sharps container for needle disposal
- Clean workspace
- Calculator (or use ours below)
The Reconstitution Process
Step 1: Prepare Your Workspace
- Clean, flat surface
- Good lighting
- All supplies within reach
- Wash hands thoroughly
Step 2: Let Peptide Reach Room Temperature
- Remove from refrigerator
- Wait 15-20 minutes
- Cold peptide + warm water can cause shock to the compound
Step 3: Clean the Vial Tops
- Wipe peptide vial top with alcohol swab
- Wipe BAC water vial top with alcohol swab
- Let dry 10 seconds
Step 4: Draw Up Bacteriostatic Water
Determining the amount:
This is where most people get confused. Here's the simple approach:
| Peptide Amount | BAC Water | Result per 0.1mL (10 units) |
|---|---|---|
| 5mg | 1mL | 500mcg per 0.1mL |
| 5mg | 2mL | 250mcg per 0.1mL |
| 10mg | 1mL | 1000mcg per 0.1mL |
| 10mg | 2mL | 500mcg per 0.1mL |
The formula:
mcg per 0.1mL = (peptide mg × 1000) ÷ (mL of water × 10)
Example: 5mg BPC-157 + 2mL BAC water
- 5 × 1000 = 5000mcg total
- 5000 ÷ 20 = 250mcg per 0.1mL
Draw up your calculated amount of BAC water.
Step 5: Add Water to Peptide (CRITICAL)
This is the most important step:
- Insert needle through rubber stopper
- AIM AT THE VIAL WALL, NOT THE POWDER
- Push plunger SLOWLY
- Let water run down the side of the vial
- Do NOT squirt directly onto powder
Why? Direct water impact can denature proteins. Gentle introduction preserves peptide integrity.
Step 6: Let It Dissolve
- DO NOT shake vigorously
- Gently swirl if needed
- Usually dissolves within 1-3 minutes
- Should be completely clear when done
- Cloudiness or particles = problem
Step 7: Storage
- Refrigerate immediately (2-8°C / 36-46°F)
- Protect from light
- Use within 28 days
- Never freeze reconstituted peptide
Common Mistakes to Avoid
1. Squirting Water Directly on Powder
This is the #1 mistake. It can denature the peptide instantly. Always let water run down the vial wall.
2. Using Sterile Water Instead of BAC Water
Sterile water has no preservative. Once opened:
- Must use entire vial immediately
- No multi-use capability
- Higher contamination risk
3. Shaking the Vial
Vigorous shaking creates air bubbles and can damage peptide structures. Gentle swirling is fine.
4. Wrong Math
Double-check your calculations. A 10x dosing error is dangerous.
5. Improper Storage
Reconstituted peptides MUST be refrigerated. Room temperature degrades them rapidly.
6. Reusing Needles
Every penetration of the rubber stopper should use a fresh needle. Reusing dulls the needle and risks contamination.
Dosing Calculations Made Easy
Insulin Syringe Units
Standard insulin syringes show "units" (IU):
- 100-unit syringe = 1mL total volume
- 50-unit syringe = 0.5mL total volume
- 10 units = 0.1mL
Quick Reference Chart
For 5mg peptide reconstituted with 2mL BAC water:
| Desired Dose | Draw This Many Units |
|---|---|
| 100mcg | 4 units |
| 250mcg | 10 units |
| 500mcg | 20 units |
| 750mcg | 30 units |
For 10mg peptide reconstituted with 2mL BAC water:
| Desired Dose | Draw This Many Units |
|---|---|
| 250mcg | 5 units |
| 500mcg | 10 units |
| 1000mcg | 20 units |
| 1500mcg | 30 units |
The Universal Formula
Units to draw = (desired dose in mcg × total mL water × 100) ÷ (peptide mg × 1000)
Skip the math entirely → Use our free Reconstitution Calculator to get exact measurements instantly.
Injection Basics
Subcutaneous (Most Common)
- Inject into fatty tissue (stomach, thigh, upper arm)
- 45-90 degree angle depending on fat layer
- Rotate injection sites
- Pinch skin, inject slowly, release
Intramuscular (Less Common)
- Deeper injection into muscle
- Typically for certain peptides (less common)
- Longer needle required
- More precise placement needed
General Best Practices
- Clean injection site with alcohol
- Let alcohol dry completely (reduces sting)
- Inject slowly and steadily
- Remove needle, apply light pressure
- Don't rub the area
Troubleshooting
Peptide Won't Dissolve
- Give it more time (up to 5 minutes)
- Very gentle swirling
- If chunks remain after 10 minutes, peptide may be damaged
- Check expiration date
Solution Is Cloudy
- May indicate contamination or denaturation
- Don't use if persistently cloudy
- Some temporary cloudiness during dissolving is normal
Numbers Don't Add Up
- Recheck your peptide amount (5mg? 10mg?)
- Recheck your water amount
- Use a calculator—don't guess
Pain at Injection Site
- May be injecting too fast
- May be too shallow
- May be sensitivity to benzyl alcohol (rare)
- Ensure alcohol dried before injecting
Summary Checklist
Before reconstitution:
- Peptide at room temperature
- Bacteriostatic water ready
- Clean syringes and needles
- Alcohol swabs
- Math calculated correctly
During reconstitution:
- Vial tops cleaned
- Water added SLOWLY down vial wall
- Not shaken
- Dissolved completely
- Solution is clear
After reconstitution:
- Stored in refrigerator immediately
- Label with date
- Calculate per-injection units
- Use within 28 days
Ready to Calculate Your Doses?
Don't risk dosing errors. Our free Reconstitution Calculator does all the math for you:
- Enter your peptide amount (mg)
- Enter your water volume (mL)
- Get exact syringe units for any dose
→ Open Reconstitution Calculator
This is educational content about research compound preparation. Always follow proper safety protocols and research your specific compounds thoroughly.
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