High-purity 2ml bac water (bacteriostatic water for injection/reconstitution) serves as a sterile diluent specifically formulated for the solubilization and preservation of lyophilized research compounds. Containing 0.9% benzyl alcohol as a microbial inhibitor, this small-volume diluent prevents bacterial growth, allowing researchers to draw multiple aliquots over extended experimental timelines. PX1 Research provides USA-manufactured, endotoxin-tested diluents backed by lot-specific third-party certificates of analysis.
High-purity 2ml bac water (bacteriostatic water for injection/reconstitution) serves as a sterile diluent specifically formulated for the solubilization and preservation of lyophilized research compounds. Containing 0.9% benzyl alcohol as a microbial inhibitor, this small-volume diluent prevents bacterial growth, allowing researchers to draw multiple aliquots over extended experimental timelines. PX1 Research provides USA-manufactured, endotoxin-tested diluents backed by lot-specific third-party certificates of analysis.
2ml bac water (bacteriostatic water) is a sterile, non-pyrogenic preparation of purified water containing 0.9% (9 mg/mL) benzyl alcohol added as a bacteriostatic preservative. It is engineered specifically for solubilizing lyophilized synthetic peptides, proteins, and reagents prior to in vitro testing, assay preparation, or preclinical animal model administration.
The inclusion of 0.9% benzyl alcohol inhibits the viability and proliferation of most gram-positive and gram-negative bacteria, as well as fungi, which may be introduced during repeated container entry. Providing a 2ml volume allows research laboratories to reconstitute small-batch peptide vials without introducing excess diluent volume, minimizing waste and reducing the risk of preservative degradation over extended storage periods.
At the chemical level, research-grade 2ml bac water consists of ultra-pure water for injection (WFI) quality solvent combined with pharmaceutical-grade benzyl alcohol ($C_7H_8O$). The solution is adjusted to a pH range of 4.5 to 7.0 using hydrochloric acid or sodium hydroxide as required during processing. The osmolarity of the solution remains low, making it an ideal solvent for delicate secondary and tertiary peptide protein structures.
Benzyl alcohol acts as a bacteriostatic agent by altering bacterial cell membrane permeability, disrupting enzymatic processes, and preventing cellular division. Unlike bactericidal agents that rapidly lyse cells and potentially release cellular debris or endotoxins into the solution, a bacteriostatic preservative halts microbial replication without compromising the chemical integrity of sensitive research peptides such as BPC-157 or TB-500.
The 2ml fill volume is sealed under inert gas in USP Type I borosilicate glass vials, minimizing alkali leaching and gas exchange over time. This ensures that the diluent maintains its strict physicochemical specifications throughout its stated shelf life.
Synthetic peptides are routinely synthesized, purified via reverse-phase high-performance liquid chromatography (RP-HPLC), and isolated as dry lyophilized cakes. In this solid state, peptides demonstrate high thermodynamic stability; however, analytical testing and in vitro assays require transition into an aqueous solution.
When reconstituting lyophilized peptides, selecting the appropriate solvent is critical. Plain sterile water (Sterile Water for Injection) lacks a preservative system. Once a sterile water vial is breached, any airborne microbe introduced into the solution can multiply rapidly at room temperature or even under refrigeration (2°C–8°C). Using 2ml bac water ensures that reconstituted compounds retain structural stability while preventing microbial contamination during multi-use experimental protocols.
Furthermore, improper solubilization can lead to peptide aggregation, precipitation, or hydrolysis. The low ionic strength and controlled pH of 2ml bac water allow efficient solvation of hydrophilic and moderately hydrophobic peptide sequences. For detailed solubilization protocols across various peptide sequences, researchers can consult our comprehensive peptide reconstitution guide.
Laboratory protocols often require choosing between several aqueous diluents, including 2ml bac water, standard Sterile Water for Injection (SWFI), 0.9% Sodium Chloride (Normal Saline), and larger volume bacteriostatic solvents. Understanding the operational differences between these media is necessary for experimental design.
Sterile Water for Injection (SWFI) contains no antimicrobial agents and is strictly intended for single-entry procedures. Once opened, unused portions must be discarded immediately to avoid contamination. Conversely, 2ml bac water maintains bacteriostatic efficacy for up to 28 days post-initial entry when stored under appropriate laboratory refrigeration. Compared to 0.9% Sodium Chloride, which introduces sodium and chloride ions that may induce salting-out effects or alter ionic strength in sensitive enzyme assays, bac water provides an uncharged, low-osmolality aqueous environment.
When evaluating volume formats, 2ml vials present distinct advantages over larger 10ml or 30ml containers. For low-mass peptide vials (e.g., 2mg to 5mg cakes), a 2ml diluent volume provides optimal molar concentration ranges without over-diluting the sample. Researchers working with a high volume of diverse targets can review our all peptides catalog to pair specific compounds with the precise diluent volume required.
Small-volume bacteriostatic water packaging offers practical and economic advantages in rigorous laboratory environments:
- **Reduced Waste:** High-throughput screening and small-scale preclinical studies often require minimal fluid volumes. A 2ml format eliminates the disposal of unused, expired multi-dose diluent.
- **Lower Risk of Cross-Contamination:** Re-entering a single multi-dose vial dozens of times increases the statistical probability of core septum shearing or mechanical contamination. Smaller 2ml units limit total needle penetrations per vial.
- **Consistent Benzyl Alcohol Volatility Control:** Repeated headspace exposure in large vials can lead to slight evaporation or degradation of volatile preservatives. The 2ml geometry minimizes headspace volume, preserving the precise 0.9% concentration across all aliquots.
- **Optimized Concentration Calculations:** Solubilizing a standard 2mg or 5mg research cake with 1ml or 2ml of diluent yields straightforward volumetric concentration ratios (e.g., 1mg/mL or 2.5mg/mL), simplifying quantitative dilution series in spectrophotometric or cell culture assays.
In vitro data indicate that solvent purity directly correlates with assay reproducibility. Trace organic impurities, high heavy metal content, or elevated endotoxin levels in diluents can artifactually alter cell viability assays, enzyme kinetics, or receptor binding affinities.
Preclinical research models require reconstituted compounds to be free of pyrogens. Endotoxins—lipopolysaccharides (LPS) derived from the outer membrane of Gram-negative bacteria—trigger inflammatory cascades in cell lines and animal tissue preparations. Using endotoxin-tested 2ml bac water guarantees that observed cellular responses stem solely from the test peptide rather than background endotoxin contamination.
Researchers performing binding studies, mass spectrometry preparation, or cellular signaling cascades can access technical documentation and assay data via our dedicated research hub.
To preserve compound integrity and maintain sterility during reconstitution using 2ml bac water, researchers should follow strict aseptic laboratory protocols:
1. **Preparation:** Sanitize the laminar flow hood or biosafety cabinet. Allow the 2ml bac water vial and the target lyophilized peptide vial to equilibrate to room temperature.
2. **Septum Disinfection:** Swab the rubber stoppers of both the diluent vial and the peptide vial with 70% isopropyl alcohol. Allow stoppers to air dry completely.
3. **Fluid Transfer:** Using a sterile, single-use laboratory syringe, draw the calculated volume of 2ml bac water (e.g., 1.0 mL or 2.0 mL). Direct the needle tip against the inner glass wall of the peptide vial rather than spraying directly onto the lyophilized cake to prevent shear stress and foaming.
4. **Dissolution:** Gently swirl the vial in a circular motion until the lyophilized powder is completely dissolved. Avoid vigorous shaking, which can denature delicate peptide tertiary structures.
5. **Storage:** Label the reconstituted solution with the date, final concentration, and compound identity. Store at 2°C–8°C for short-term evaluation, or aliquot and freeze at -20°C to -80°C for long-term stability, avoiding repeated freeze-thaw cycles.
Not all laboratory reagents meet the stringent criteria required for reproducible scientific research. PX1 Research enforces strict quality assurance protocols for all diluents and research compounds:
- **ISO 17025 Third-Party Testing:** Every lot of 2ml bac water undergoes independent testing by an accredited laboratory to verify identity, purity, and chemical composition.
- **Endotoxin Quantification:** Using the Limulus Amebocyte Lysate (LAL) assay, diluent lots are verified to contain <0.25 EU/mL endotoxin, exceeding standard research benchmarks.
- **RP-HPLC and Gas Chromatography:** Benzyl alcohol content is quantitatively verified via chromatographic analysis to guarantee exact 0.9% concentration without degrading contaminants or trace organic impurities.
- **Sterility Testing:** Vials undergo incubation testing according to USP protocols to confirm the complete absence of bacterial and fungal growth.
Principal investigators and procurement officers requiring volume supplies or custom packaging specifications can learn more about institutional options via our wholesale portal.
PX1 Research is dedicated to supporting scientific discovery by supplying premium-grade reagents manufactured strictly within the USA in compliance with cGMP standards. Every batch of 2ml bac water undergoes rigorous quality control checks before release.
To protect temperature-sensitive reagents and prevent supply chain delays, all orders ship directly from our centralized distribution facilities in California and Arizona. Orders placed Monday through Friday ship same-day, ensuring that your research team maintains steady workflow timelines.
By pairing high-purity peptides with fully verified, low-endotoxin 2ml bac water, laboratory facilities ensure maximum analytical reproducibility, sample stability, and experimental integrity.
What is 2ml bac water used for in a laboratory setting?
2ml bac water (bacteriostatic water) is used as a sterile solvent to reconstitute lyophilized research peptides and proteins. The included 0.9% benzyl alcohol prevents bacterial proliferation, allowing researchers to draw multiple samples from a single reconstituted vial over time.
How long is 2ml bac water stable after the initial septum entry?
Once entered using sterile laboratory technique, 2ml bac water remains bacteriostatic for up to 28 days when stored at refrigerated temperatures (2°C–8°C). After 28 days, the vial should be safely discarded.
Can 2ml bac water be used for frozen peptide storage?
While 2ml bac water is ideal for liquid storage at 2°C–8°C, freezing reconstituted solutions containing benzyl alcohol is generally not recommended for long-term storage, as freezing can cause benzyl alcohol precipitation or phase separation. For freezing, single-use sterile water or specialized buffer solutions are preferred.
What is the endotoxin limit for PX1 Research 2ml bac water?
PX1 Research 2ml bac water is verified via third-party LAL testing to contain endotoxin levels strictly below 0.25 EU/mL, ensuring compatibility with sensitive in vitro assays and preclinical models.
Why choose 2ml bac water over 10ml or 30ml vials?
The 2ml volume is ideal for reconstituting single 2mg to 5mg peptide vials. It minimizes unused reagent waste, limits the number of septum penetrations, and reduces the risk of preservative evaporation over time compared to larger volume containers.
What is the difference between 2ml bac water and Sterile Water for Injection (SWFI)?
2ml bac water contains 0.9% benzyl alcohol as a bacteriostatic preservative, making it suitable for multi-entry use over a 28-day period. SWFI contains no preservative and must be used immediately as a single-use diluent.
How should unopened 2ml bac water vials be stored?
Unopened vials of 2ml bac water should be stored at controlled room temperature (20°C to 25°C / 68°F to 77°F) protected from light. Avoid excessive heat or freezing temperatures prior to reconstitution.
Where does PX1 Research manufacture and ship its 2ml bac water?
All PX1 Research reagents and diluents are manufactured in USA-based cGMP-compliant facilities and shipped directly from fulfillment centers located in California and Arizona, featuring same-day shipping for weekday orders.
All products are sold strictly for laboratory and research use only. Not for human or veterinary use, diagnosis, treatment or consumption. Statements have not been evaluated by the FDA.