Accessories
BD Micro-Fine Syringe 1ml —
From£4.99
Free shipping over £100
Laboratory-grade bacteriostatic water for accurate, sterile peptide reconstitution in research settings.
Correct reconstitution is a foundational step in any peptide research protocol. The physical and chemical stability of a peptide in solution is determined not only by the peptide's intrinsic properties — sequence, charge distribution, and disulfide bond content — but also by the solvent used, the pH of the resulting solution, and the presence or absence of antimicrobial agents that permit multi-use without microbial contamination. Bacteriostatic water for injection (BWI) contains 0.9% benzyl alcohol, a preservative that inhibits microbial growth in opened vials and is compatible with the reconstitution requirements of the majority of research peptides supplied in lyophilised form.
The choice of diluent directly affects the integrity of downstream experimental data. Using non-sterile solvents introduces the risk of endotoxin contamination, which can confound cytokine and inflammatory signalling readouts at concentrations as low as 0.1 EU/mL. Bacteriostatic water supplied at research and pharmaceutical grade provides a defined, consistent matrix for reconstitution, enabling reproducible concentration calculations and reducing the variability introduced by inconsistent solvent quality. For acidic or basic peptides with limited aqueous solubility, the initial reconstitution step in a small volume of bacteriostatic water is often followed by dilution in the appropriate assay buffer — a procedure that this diluent supports without introducing reactive species that could modify sensitive amino acid residues.
Bacteriostatic water contains 0.9% benzyl alcohol as a preservative, which inhibits the growth of common bacterial and fungal contaminants following vial puncture. Sterile water for injection contains no preservative and is intended for single-use only — once punctured, the vial is no longer considered sterile. In research settings where a reconstituted peptide stock may be accessed repeatedly over days or weeks, bacteriostatic water provides a microbiologically safer diluent and reduces the risk of contamination-related experimental artefacts.
At the 0.9% concentration used in bacteriostatic water, benzyl alcohol is not expected to react chemically with the peptide backbone under normal storage conditions (2–8 °C). However, peptides with free thiol groups (e.g., cysteine-containing sequences) or those susceptible to oxidation should be assessed for compatibility, as benzyl alcohol can act as a mild pro-oxidant under certain conditions. Researchers should include appropriate vehicle controls — using bacteriostatic water at the same final dilution as the peptide preparation — to confirm that any observed biological effects are attributable to the peptide and not the diluent.
The general procedure is to allow the lyophilised peptide vial to equilibrate to room temperature before opening, to minimise condensation. Bacteriostatic water should be injected slowly down the inside wall of the vial — not directly onto the lyophilised cake — to prevent foaming and mechanical shearing of the peptide. The vial should then be gently swirled (not vortexed) until the cake fully dissolves. If the peptide does not dissolve readily, a brief sonication (1–2 minutes) or a change to a lower pH diluent (for basic peptides) may be required. Researchers should record the volume added to calculate the resulting molar concentration accurately.
Once reconstituted in bacteriostatic water, most peptide solutions should be stored at 2–8 °C and used within 2–4 weeks, though stability varies significantly by peptide sequence, concentration, and pH of the reconstituted solution. For longer-term storage, aliquoting into single-use volumes and storing at −20 °C or −80 °C is recommended to minimise freeze-thaw-induced aggregation and hydrolytic degradation. Researchers should avoid repeated freeze-thaw cycles, as these promote the formation of high-molecular-weight aggregates that can reduce bioactivity and introduce variability into dose-response data.
All products sold by Neovia Peptides are strictly for in-vitro research and laboratory use only. Not intended for human or veterinary use, food additives, drugs, or cosmetics. By purchasing from this website, you agree that you understand and accept these terms.
