Dose-Yield Reference
How Many Doses Can You Get from a 30 mL (or 10 mL) Bacteriostatic Water Vial?
A 10 mL vial yields 50–200 research draws by pure volume, depending on draw size. A 30 mL vial yields 150–600. The actual limit in practice is the 28-day post-puncture in-use window, not vial volume — most researchers use 10 mL vials because the volume math matches the bacteriostatic window cleanly.
Direct Answer
10 mL = ~100 doses at 0.10 mL each. 30 mL = ~300 doses at 0.10 mL each. But the 28-day refrigerated in-use limit usually caps practical dose count below that — 28 draws on a daily protocol, 4 on a weekly protocol. Pick vial size to match how fast you'll actually use it.
Dose Count by Vial Size & Draw Volume
Maximum theoretical draws by pure volume. Actual usable count is constrained by the 28-day in-use window.
| Vial Size | Draw Volume | Max Doses (Volume) | Equivalent Peptide Reconstitutions |
|---|---|---|---|
| 10 mL vial | 0.05 mL (5 units) | 200 doses | ≈ 50 vials of 4 mL reconstituted peptide |
| 10 mL vial | 0.10 mL (10 units) | 100 doses | ≈ 25 vials of 4 mL reconstituted peptide |
| 10 mL vial | 0.20 mL (20 units) | 50 doses | ≈ 12 vials of 4 mL reconstituted peptide |
| 30 mL vial | 0.05 mL (5 units) | 600 doses | ≈ 150 vials of 4 mL reconstituted peptide |
| 30 mL vial | 0.10 mL (10 units) | 300 doses | ≈ 75 vials of 4 mL reconstituted peptide |
| 30 mL vial | 0.20 mL (20 units) | 150 doses | ≈ 37 vials of 4 mL reconstituted peptide |
Frequently Asked Questions
How many doses can I get from a 10 mL bacteriostatic water vial?
Pure volume math: a 10 mL vial yields 100 draws of 0.10 mL, 50 draws of 0.20 mL, or 200 draws of 0.05 mL. In practice, the constraint is rarely volume — it's the 28-day post-puncture in-use window. If your research protocol draws once per day at 0.10 mL, a 10 mL vial holds 100 doses but only 28 are usable inside the bacteriostatic window. If your protocol draws weekly, all 100 doses are usable.
How many doses from a 30 mL bacteriostatic water vial?
Pure volume math: a 30 mL vial yields 300 draws at 0.10 mL each or 600 draws at 0.05 mL each. The same 28-day in-use limit applies — at one draw per day, you'd use 28 doses out of 300 available, so a 30 mL single vial is usually oversized for a single research workstream. 30 mL is appropriate when reconstituting multiple peptide vials from one bacteriostatic water source within the 28-day window.
Why is the answer not 'as many as the volume allows'?
Bacteriostatic water's preservative effectiveness is rated for 28 days post-puncture under refrigeration. Beyond that window, the benzyl alcohol concentration can no longer guarantee microbial suppression. Most research protocols treat 28 days as a hard discard date regardless of remaining volume — so practical dose count = (28 days) × (draws per day) × (mL per draw), not (vial volume) ÷ (mL per draw).
Should I buy 10 mL or 30 mL vials for peptide research?
10 mL is the standard research-supply size because it pairs cleanly with the 28-day in-use window. A typical peptide reconstitution workflow uses 2–4 mL of bacteriostatic water per peptide vial. A 10 mL vial reconstitutes 2–5 peptide vials and is fully used inside 28 days. 30 mL is appropriate for higher-throughput labs reconstituting many peptide vials simultaneously, or where the bacteriostatic water itself is being used as the primary diluent for a multi-peptide research panel.
Can I make one 30 mL vial last longer than 28 days?
Not safely. The 28-day window is the manufacturer's recommended in-use limit while the preservative is active and the vial integrity is best preserved. Some research protocols extend the window with strict aseptic technique, but extending beyond 28 days introduces microbial-growth risk that compromises the research validity of downstream peptide work. Standard practice is to discard and start a fresh vial.
What's the most cost-effective size for ongoing peptide research?
For most researchers, two-to-four 10 mL vials per month outperforms a single 30 mL vial on cost-per-usable-mL, because most or all of the smaller vials' volume gets used inside the window. BAC Water Depot 10 mL vials start at $6.49 per vial in bulk — at that price, two vials per month is $13 in diluent cost for an entire peptide research protocol.
Right-size your bacteriostatic water order.
10 mL vials are the standard research format — fresh vial every 28 days, full preservative effectiveness, predictable cost.
