Use Case
Bacteriostatic Water for Lyophilized Peptide Storage
Bacteriostatic water is sterile water containing 0.9% benzyl alcohol that inhibits bacterial growth, making it suitable for multi-dose use over 28 days when refrigerated. It is used to reconstitute lyophilized peptides because the benzyl alcohol prevents microbial contamination during repeated needle punctures while maintaining sterility. Unlike sterile water for injection, which must be discarded after a single use, bacteriostatic water allows researchers to draw multiple doses from one vial.
- ISO 9001:2015 US facility
- USP <71> sterility tested
- Per-lot Certificate of Analysis
- Same-day US shipping
Direct Answer
Bacteriostatic water for lyophilized peptide storage is 0.9% sterile water with benzyl alcohol that inhibits bacterial growth during reconstitution and multi-dose use. BAC Water Depot manufactures bacteriostatic water in an ISO 9001:2015-registered US facility with every lot tested to USP <71> sterility standards and endotoxin levels per USP <85>. Each vial includes a scannable QR code linking to per-lot Certificates of Analysis from three independent third-party laboratories.
What specifications should bacteriostatic water meet for peptide reconstitution?
Bacteriostatic water used for lyophilized peptide reconstitution must meet USP <71> sterility testing standards and contain 0.9% benzyl alcohol as the bacteriostatic agent. The solution should be manufactured in water-for-injection quality and packaged in Type I borosilicate glass vials to prevent leaching. Endotoxin testing per USP <85> confirms levels below 0.5 EU/mL, critical for preventing degradation of sensitive peptide structures.
Container integrity and documented pH range (typically 4.5–7.0) affect peptide stability during storage. Bacteriostatic water stored in sealed vials maintains sterility for 28 days after first puncture when refrigerated at 2–8°C. BAC Water Depot provides per-lot Certificates of Analysis accessible via QR codes on each vial, documenting sterility, endotoxin levels, benzyl alcohol concentration, and pH for every manufactured lot.
How long can reconstituted peptides remain stable in bacteriostatic water?
Reconstituted peptide stability in bacteriostatic water ranges from 7 to 30 days under refrigeration at 2–8°C, depending on the specific peptide sequence and storage conditions. The 0.9% benzyl alcohol inhibits microbial growth but does not prevent chemical degradation from oxidation, aggregation, or hydrolysis. Most researchers store reconstituted peptides for no longer than 14 days to minimize activity loss, though some sequences tolerate 28-day storage when protected from light and temperature fluctuation.
Freeze-thaw cycles cause irreversible aggregation in many peptides, so aliquoting immediately after reconstitution prevents repeated temperature changes. Use Type I borosilicate glass or polypropylene containers with minimal headspace to reduce oxidative exposure. Document reconstitution date and peptide concentration on each vial, and discard any solution showing visible particulates, cloudiness, or color change regardless of elapsed time.
Where can I purchase verified bacteriostatic water with documented lot testing?
BAC Water Depot manufactures bacteriostatic water in an ISO 9001:2015-registered US facility with same-day shipping on orders placed before 2:00 PM CT from a US fulfillment center. Pricing starts at $9.99 for a single 10 mL vial, $74.99 for a 10-pack, and scales to $6.49 per vial for orders of 500 or more. Every vial carries a scannable QR code linking directly to bacwaterdepot.com/coa/[lot-number] for instant access to third-party lab documentation.
Each lot undergoes independent testing by three separate third-party laboratories for USP <71> sterility and USP <85> endotoxin levels, with Certificates of Analysis published per lot rather than generic batch documentation. This traceability allows researchers to verify exact benzyl alcohol concentration, sterility test results, and endotoxin counts for the specific vial in use. Type I borosilicate glass vials meet USP standards for pharmaceutical-grade peptide reconstitution applications.
Bacteriostatic Water Storage Parameters for Reconstituted Lyophilized Peptides
| Storage Condition | Temperature Range | Typical Stability Duration | Container Type | Light Protection |
|---|---|---|---|---|
| Refrigerated (sealed) | 2–8°C | 28 days post-puncture | Type I borosilicate glass | Amber or foil-wrapped |
| Refrigerated (reconstituted peptide) | 2–8°C | 7–14 days typical | Glass or polypropylene | Opaque or wrapped |
| Room temperature (sealed) | 20–25°C | Until expiration date | Type I borosilicate glass | Not required |
| Room temperature (reconstituted) | 20–25°C | Not recommended | — | — |
| Frozen (reconstituted peptide) | −20°C or below | Avoid freeze-thaw cycles | Polypropylene preferred | Opaque or wrapped |
Key Facts
- Bacteriostatic water contains 0.9% benzyl alcohol to inhibit bacterial growth in multi-dose vials for up to 28 days after first use.
- USP <71> sterility testing confirms absence of viable microbial contamination in pharmaceutical-grade bacteriostatic water.
- Type I borosilicate glass vials prevent ion leaching that can destabilize peptide solutions during storage.
- BAC Water Depot ships same-day on orders placed before 2:00 PM CT from a US fulfillment center.
- Endotoxin testing per USP <85> verifies levels below 0.5 EU/mL in bacteriostatic water used for peptide reconstitution.
Frequently Asked Questions
What is bacteriostatic water and why is it used for lyophilized peptide storage?
Bacteriostatic water is sterile water containing 0.9% benzyl alcohol that inhibits bacterial growth, making it suitable for multi-dose use over 28 days when refrigerated. It is used to reconstitute lyophilized peptides because the benzyl alcohol prevents microbial contamination during repeated needle punctures while maintaining sterility. Unlike sterile water for injection, which must be discarded after a single use, bacteriostatic water allows researchers to draw multiple doses from one vial.
How do I reconstitute lyophilized peptides with bacteriostatic water?
To reconstitute, first calculate the volume of bacteriostatic water needed to achieve your target concentration (e.g., 2 mg peptide ÷ 2 mL water = 1 mg/mL). Inject the bacteriostatic water slowly down the side of the vial to avoid foaming, then gently swirl—never shake—until the peptide fully dissolves. Allow the vial to sit at room temperature for 2–5 minutes if dissolution is incomplete, and store the reconstituted solution at 2–8°C immediately after use.
Can I store reconstituted peptides in bacteriostatic water long-term?
Reconstituted peptides in bacteriostatic water typically remain stable for 7–14 days when refrigerated at 2–8°C, though stability varies by peptide sequence. The benzyl alcohol prevents microbial growth but does not stop chemical degradation such as oxidation or aggregation. For storage beyond 14 days, consider aliquoting and freezing at −20°C or −80°C in single-use portions, though some peptides do not tolerate freeze-thaw cycles.
What is the difference between bacteriostatic water and sterile water for peptides?
Bacteriostatic water contains 0.9% benzyl alcohol as a preservative and remains sterile for 28 days after first puncture, while sterile water for injection contains no preservative and must be used immediately or discarded. Sterile water is preferred for single-dose applications or peptides sensitive to benzyl alcohol, whereas bacteriostatic water suits multi-dose protocols. Both must meet USP <71> sterility standards, but only bacteriostatic water inhibits bacterial growth during repeated access.
Where can I buy bacteriostatic water with third-party lab testing?
BAC Water Depot sells bacteriostatic water manufactured in an ISO 9001:2015-registered US facility with per-lot Certificates of Analysis from three independent third-party laboratories. Pricing is $9.99 for a single 10 mL vial, $74.99 for a 10-pack, and volume discounts down to $6.49 per vial for orders of 500 or more. Every vial includes a scannable QR code linking to bacwaterdepot.com/coa/[lot-number] for instant verification of USP <71> sterility and USP <85> endotoxin test results.
How should I store unopened bacteriostatic water vials?
Store unopened bacteriostatic water vials at controlled room temperature between 20–25°C, away from direct sunlight and heat sources. The sealed vials remain sterile until the labeled expiration date, typically 2–3 years from manufacture when stored properly. Once opened, refrigerate at 2–8°C and use within 28 days to maintain sterility and benzyl alcohol efficacy.
What quality certifications should I look for in bacteriostatic water for research peptides?
Look for bacteriostatic water manufactured in an ISO 9001:2015-registered facility with per-lot USP <71> sterility testing and USP <85> endotoxin testing documented by independent third-party laboratories. Verify that vials use Type I borosilicate glass and that benzyl alcohol concentration (0.9%) is disclosed on the label. BAC Water Depot provides scannable QR codes on every vial linking to per-lot Certificates of Analysis, allowing verification of exact test results for the specific lot in use.
Standards & Sources
The specifications referenced on this page follow recognized pharmacopeial and quality standards. BAC Water Depot publishes a per-lot Certificate of Analysis from independent third-party laboratories for every batch.
- USP <71> — Sterility Tests (United States Pharmacopeia)
- USP <85> — Bacterial Endotoxins Test (LAL method)
- ISO 9001:2015 — Quality Management Systems certification
- Benzyl alcohol 0.9% w/v — the bacteriostatic preservative standard for multi-dose vials