5 ml bac water (bacteriostatic water) is a sterile, non-pyrogenic solution of 0.9% (9 mg/mL) benzyl alcohol dissolved in purified Water for Injection, engineered for the reconstitution of lyophilized research compounds. Supplied exclusively for laboratory research use, this diluent inhibits bacterial proliferation to maintain reagent integrity across multi-withdrawal in vitro and preclinical experimental trials.
5 ml bac water (bacteriostatic water) is a sterile, non-pyrogenic solution of 0.9% (9 mg/mL) benzyl alcohol dissolved in purified Water for Injection, engineered for the reconstitution of lyophilized research compounds. Supplied exclusively for laboratory research use, this diluent inhibits bacterial proliferation to maintain reagent integrity across multi-withdrawal in vitro and preclinical experimental trials.
In analytical chemistry and preclinical research, maintaining the chemical integrity of solubilized peptides is paramount. Standard purified water lacks antimicrobial agents, rendering reconstituted solutions highly susceptible to microbial contamination upon exposure to ambient air or repeated needle punctures. 5 ml bac water addresses this limitation by incorporating 0.9% (9 mg/mL) benzyl alcohol as a bacteriostatic preservative suspended in high-purity, sterile water for injection.
The primary mechanism of action of benzyl alcohol centers on its ability to alter bacterial cell membrane fluidity. At a concentration of 0.9%, benzyl alcohol inserts into the lipid bilayer of prokaryotic cell walls, disrupting membrane permeability and uncoupling electron transport chains. This action halts bacterial replication without immediately denaturing or cross-linking sensitive peptide chains. Consequently, research peptides reconstituted in 5 ml bac water remain biologically stable and microbiologically inert throughout extended testing windows.
PX1 Research supplies 5 ml bac water formulated specifically to meet stringent laboratory standards. The solution exhibits a pH range of 4.5 to 7.0, optimized to match the stability profiles of most synthetic peptide sequences. The total dissolved solids and ionic strength are kept at absolute minimal thresholds to prevent unwanted salt precipitation or ionic interference during downstream spectrophotometric, mass spectrometry, or cell assay evaluations.
When solubilizing dry peptide cakes, the volume of diluent dictates the final molarity and concentration (e.g., mg/mL) of the stock solution. Utilizing a standard 5 mL vial size allows researchers to prepare precise intermediate concentrations for multi-well plate assays or longitudinal preclinical studies without generating excessive reagent waste. All 5 mL vials are sealed with fluoropolymer-coated butyl rubber stoppers and flip-off aluminum crimps to preserve vacuum integrity and prevent leaching of elastomeric compounds into the research solution.
Selecting the correct solvent is critical for experimental reproducibility. While single-use diluents like sterile water for injection provide an unpreserved matrix suitable for immediate single-dose solubilization, they lack antimicrobial preservation and must be discarded immediately after opening to prevent contamination.
Conversely, specialized diluents such as 0.9% sodium chloride reconstituted solutions provide isotonicity but introduce sodium and chloride ions that can induce aggregation or altering tertiary folding in certain highly hydrophobic research peptides. 5 ml bac water balances broad compound compatibility with robust antimicrobial defense, making it the preferred universal diluent for multi-use laboratory stock solutions.
Proper reconstitution technique is essential to preserve peptide secondary structure and maintain accurate volumetric concentrations. When handling 5 ml bac water in a biosafety cabinet or clean bench environment, researchers should adhere to standardized aseptic procedures:
1. Disinfect the rubber stoppers of both the 5 ml bac water vial and the lyophilized peptide vial (such as BPC-157 5mg or Semaglutide 5mg) using a fresh 70% isopropyl alcohol wipe. 2. Draw the precise calculated volume of 5 ml bac water into a sterile, low-dead-space laboratory syringe. 3. Insert the syringe needle through the peptide vial stopper at a 45-degree angle, aiming the stream along the glass container wall rather than directly onto the lyophilized powder cake to minimize mechanical shear stress. 4. Allow the diluent to slowly submerge the powder. Gently swirl the vial in a circular motion until completely dissolved; avoid vortexing or vigorous shaking, which can induce protein denaturation or foaming. 5. Inspect the clear liquid visually for any un-dissolved particulate matter before withdrawing aliquots for testing.
Unopened vials of 5 ml bac water should be stored at controlled room temperature (20°C to 25°C / 68°F to 77°F) away from direct light exposure and extreme thermal fluctuations. Under these conditions, the sealed vial remains stable through the expiration date stamped on the product label.
Once punctured, the benzyl alcohol preservative maintains bacteriostatic efficacy for up to 28 days under refrigerated conditions (2°C to 8°C). Researchers must record the date of initial vial entry directly on the label. Post-reconstitution peptide stability depends heavily on the individual peptide sequence; however, maintaining reconstituted stock solutions in 5 ml bac water at 2°C to 8°C retards both bacterial growth and chemical hydrolysis compared to unpreserved solutions.
To ensure zero interference with sensitive cell cultures, enzymatic assays, or liquid chromatography setups, PX1 Research subjects every batch of 5 ml bac water to rigorous quality control verification. Each lot undergoes comprehensive testing in an ISO 17025 accredited laboratory facility:
• High-Performance Liquid Chromatography (HPLC) & Mass Spectrometry (MS): Confirms exact 0.9% benzyl alcohol concentration and verifies complete absence of organic impurities or degradation products. • Endotoxin Assay (LAL Test): Ensures bacterial endotoxins remain strictly below 0.25 EU/mL, preventing endotoxin-induced cellular toxicity or inflammatory responses in in vitro assays. • USP <71> Sterility Standard: Validates total absence of viable fungal or bacterial micro-organisms following long-term incubation assays. • Heavy Metal & pH Analysis: Guarantees strict adherence to United States Pharmacopeia (USP) specifications for water purity.
While 5 ml bac water is compatible with a vast majority of synthetic signaling fragments, researchers should evaluate compound-specific solubility profiles prior to bulk reconstitution. Highly hydrophobic peptides or short-chain lipopeptides may require initial solubilization in organic solvents (such as DMSO or DMF) before secondary dilution with 5 ml bac water.
For metabolic, tissue repair, or neurobiological targets—including compounds such as Thymosin Beta-4—reconstitution in 5 ml bac water provides excellent long-term chemical stability for daily aliquot sampling during multi-week experimental schedules. Researchers can access detailed stability profiles via our laboratory research portal.
PX1 Research is dedicated to supporting scientific advancement by supplying American-manufactured, research-grade reagents built to exacting specifications. When purchasing 5 mL bacteriostatic water, research institutions gain complete supply chain transparency and analytical confidence.
Every shipment includes lot-traceable documentation, access to downloadable Certificate of Analysis (COA) files, and rapid dispatch. Operating from dual fulfillment centers in California and Arizona, PX1 Research provides same-day shipping (Monday through Friday) to eliminate operational downtime. Laboratories requiring large-volume ordering or customized reagent contracts are encouraged to visit our bulk lab ordering portal.
What is 5 ml bac water used for in a laboratory setting?
5 ml bac water is used as a sterile diluent to solubilize lyophilized research peptides and proteins. Its 0.9% benzyl alcohol preservative prevents bacterial contamination, allowing for multi-dose sampling over a 28-day period.
What is the concentration of benzyl alcohol in 5 ml bac water?
5 ml bac water contains exactly 0.9% (9 mg/mL) benzyl alcohol USP dissolved in sterile Water for Injection.
How long does 5 ml bac water last after opening?
Once the vial stopper is first punctured, the solution remains effective as a bacteriostatic diluent for up to 28 days when stored at controlled refrigerated temperatures (2°C to 8°C).
Can 5 ml bac water be frozen?
Freezing 5 ml bac water is not recommended, as ice crystal formation can compromise container closure integrity or cause phase separation of the benzyl alcohol preservative.
Is 5 ml bac water tested for endotoxins?
Yes. Every lot of 5 ml bac water from PX1 Research undergoes Limulus Amebocyte Lysate (LAL) testing to ensure endotoxin levels remain strictly under 0.25 EU/mL.
What is the difference between 5 ml bac water and sterile water?
Sterile water contains no antimicrobial agents and must be used immediately upon opening. 5 ml bac water contains 0.9% benzyl alcohol, which inhibits microbial growth and allows multi-use sampling.
Does 5 ml bac water affect the pH of reconstituted peptide solutions?
5 ml bac water has a neutral to slightly acidic pH range (4.5 to 7.0), designed to match the chemical stability requirements of standard synthetic research peptides.
Where is PX1 Research 5 ml bac water manufactured?
All 5 ml bac water supplied by PX1 Research is manufactured in the USA within GMP-compliant, ISO 17025 certified facilities.
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.