Bacteriostatic Water for Injection, USP (10 mL) is a sterile, nonpyrogenic preparation of water for injection containing 0.9% (9 mg/mL) benzyl alcohol added as a bacteriostatic preservative. It is specifically formulated to act as a diluent or solvent for reconstituting, dissolving, or diluting medications and lyophilized compounds requiring multi-dose applications.

When working with peptides, 10 mL Bacteriostatic Water plays two critical roles: it serves as a solvent to transition freeze-dried (lyophilized) powder into an active liquid state, and it acts as an antimicrobial shield to protect the solution over time.

1. Solubilization & Structure Protection

• Dissolving Lyophilized Solids: Research peptides are manufactured via synthesis and then freeze-dried into a porous cake or powder (lyophilization) to remain stable during shipping and long-term storage. Standard water cannot dissolve these molecular structures safely without running into purity or microbial issues.

• Gentle Dissolution: Bacteriostatic water breaks the solid intermolecular bonds of the peptide powder without altering the sequence of amino acids or disrupting secondary protein structures—provided the liquid is allowed to trickle gently down the vial wall rather than sprayed directly onto the powder.

2. Antimicrobial Protection (The 0.9% Benzyl Alcohol Mechanism)

• Cell Membrane Disruption: The added 0.9% benzyl alcohol acts as a bacteriostatic agent. It penetrates the lipophilic (fat-soluble) cell membranes of bacteria and fungi that might be introduced via a needle tip during entry.

• Inhibiting Proliferation: Instead of immediately destroying all cells (which a bactericidal agent or harsh chemical would do), benzyl alcohol alters membrane permeability and disrupts essential metabolic transport within micro-organisms. This halts bacterial growth and replication, keeping the solution sterile across multiple entries for up to 28 days.

• Key Features & Technical Specifications

  • Volume: 10 mL multi-dose vial

  • Preservative: 0.9% (9 mg/mL) Benzyl Alcohol

  • Multi-Dose Design: The antimicrobial preservative inhibits bacterial and fungal growth, allowing for multiple punctures and withdrawals over time.

  • Post-Puncture Stability: Solution remains sterile for up to 28 days after initial vial puncture when handled with proper aseptic technique and stored correctly.

  • pH Range: ~5.7 (4.5 to 7.0)

  • Packaging: Hermetically sealed 10 mL glass or high-density plastic vial with a flip-off cap and self-sealing rubber stopper.

• Storage: Store at controlled room temperature (20°C to 25°C / 68°F to 77°F). Protect from freezing and excessive heat.

• Handling: Always sanitize the top rubber stopper with an alcohol wipe prior to needle insertion.