Prepared by Quanta Nova LLC · Technical review by Isaiah D., Chief Technology Officer and Head of Formulations, Quantum Innovation Labs LLC.
Updated October 18, 2026
For Quanta Nova BAC water, two dates matter: the expiration date on the vial and the date it was first accessed. Refrigeration does not extend either limit.
Store Quanta Nova BAC water at 20–25°C (68–77°F). Refrigeration is not required. Unopened vials have an assigned expiration date two years after manufacture. After the first puncture, follow Quanta Nova’s maximum of 28 days or the printed expiration date, whichever comes first.
Does BAC water need to be refrigerated?
No. Quanta Nova’s storage instructions specify 20–25°C (68–77°F). Keep the BAC-water vial within that range and follow its printed expiration date. Putting it in a refrigerator does not give it a new expiration date or extend the 28-day period after first access.
These instructions apply to Quanta Nova BAC water. For another brand, follow the directions supplied with that product. Once BAC water is mixed with a research material, the resulting solution may require different storage conditions. Follow the material’s documentation and your laboratory’s protocol.
How long does unopened bacteriostatic water last?
Quanta Nova assigns unopened BAC water an expiration date two years after manufacture when stored as directed. Use the date marked EXP on your own vial. The purchase date does not start a new two-year period.
For example, a vial marked EXP 06/30/2028 expires on that date; it does not remain within its assigned shelf life for two years after you receive it. An intact cap is also not a reason to use a vial beyond its expiration date.
How long is BAC water good for after opening?
For Quanta Nova BAC water, count from first access: the first time the stopper is punctured. Record that date. Accessing the same vial again does not restart the 28 days.
| Vial status | QN’s stated limit | What to record or check |
|---|---|---|
| Unopened | Printed EXP date; assigned two years after manufacture | Storage conditions and label |
| First accessed | Within 28 days or by EXP, whichever comes first | First-puncture date and discard date |
| Condition or handling is in doubt | Stop sooner | Seal, appearance and handling history |
The 28-day period is a handling recommendation, not a guarantee that a punctured vial remains uncontaminated throughout that time.
Why does Quanta Nova use a 28-day limit?
Quanta Nova applies it as a conservative handling recommendation for its research BAC water. Separately, CDC guidance for clinical multi-dose medication vials describes a 28-day period after first access unless a manufacturer specifies otherwise, never beyond the original expiration date. That clinical guidance is background for the recommendation; it is not a test of Quanta Nova’s product.
Does the preservative prevent contamination?
Not completely. Quanta Nova BAC water contains 0.9% benzyl alcohol as a preservative. A preservative does not replace careful handling. Stop using the vial if its seal is damaged, the liquid becomes cloudy or contains visible particles, or its handling history is uncertain. Clear appearance alone does not establish that a vial is uncontaminated.
Does a COA prove shelf life?
A certificate of analysis documents the tests performed on a batch sample. A benzyl alcohol or pH result does not, by itself, demonstrate two years of stability or establish how the vial changes after puncture. Read the listed test scope on the batch report.
The FDA’s explanation of drug expiration dates describes the relationship between stability evidence and storage conditions. It does not independently validate Quanta Nova’s assigned expiration date for this research product.
For formulation details, see what bacteriostatic water contains. For questions about a mixture, see our research compatibility guide; the BAC vial’s 28-day limit is not a stability claim for a peptide solution.
Quanta Nova BAC water is for laboratory research only, not human or animal use. This guide does not provide injection, dosing or administration instructions.
Sources and product instructions
- Quanta Nova product instructions: 20–25°C storage, assigned two-year unopened expiration and maximum 28 days after first access, subject to the earlier EXP date.
- CDC: Preventing Unsafe Injection Practices — clinical multi-dose-vial handling context.
- FDA: Expiration Dates — Questions and Answers — drug stability and expiration context.
- Manufacturer labeling: bacteriostatic water storage — independent reference for the 20–25°C temperature range, not validation of QN shelf life.
