Bacteriostatic Water (10ml)

Bacteriostatic Water is sterile water for injection containing 0.9% benzyl alcohol as a bacteriostatic preservative, supplied in 10ml sealed vials. It is the standard reconstitution vehicle for lyophilised research peptides, providing sterile, preserved aqueous solution suitable for repeated use from a single vial over an extended period.

The 0.9% benzyl alcohol concentration inhibits bacterial growth through disruption of bacterial cell membranes and inhibition of enzyme activity in contaminating microorganisms. This bacteriostatic (growth-inhibiting, not bactericidal) activity allows a single vial to be punctured multiple times over days to weeks without sterility compromise — in contrast to sterile water for injection (no preservative) which must be used immediately or single-use.

Reconstitution protocol for lyophilised research peptides: allow the sealed peptide vial and bacteriostatic water vial to equilibrate to room temperature before opening. Using a sterile syringe, withdraw the desired volume of bacteriostatic water. Insert the syringe needle through the rubber stopper of the peptide vial and inject the bacteriostatic water slowly down the inside wall of the vial rather than directly onto the lyophilised powder. Gently swirl — do not vortex vigorously — until the powder dissolves to produce a clear solution. For most Signal Labs research peptides, reconstitution at 1mg/mL (1mg powder + 1mL bacteriostatic water) provides a convenient stock concentration for serial dilution to working concentrations.

Storage of reconstituted solutions: store reconstituted peptide solutions at 4°C for short-term use (2-4 weeks for most peptides) or aliquot and store at -20°C for longer periods. Avoid repeated freeze-thaw cycles — aliquot into single-use volumes before freezing. Discard any reconstituted solution showing visible turbidity, discolouration, or particulate matter.

Benzyl alcohol considerations in research: at the concentrations present after peptide reconstitution and serial dilution to working concentrations, benzyl alcohol from bacteriostatic water does not interfere with standard research assays including ELISA, Western blot, cell viability, receptor binding, and most enzymatic assays. However, for experiments with extremely benzyl alcohol-sensitive endpoints — certain lipid assays, some mass spectrometry workflows, or assays measuring aldehyde metabolism — prepare parallel vehicle controls using bacteriostatic water at matched volumes to account for any benzyl alcohol contribution to the signal. Quality: supplied as a sterile, pyrogen-tested solution in sealed rubber-stoppered glass vials suitable for repeated puncture. Each vial is tested for bacterial endotoxins by the Limulus Amoebocyte Lysate (LAL) assay before dispatch. Store sealed vials at room temperature. Once opened, store at 4°C. Use within 28 days of first puncture. For laboratory reconstitution of research compounds only.