Bac-Water 10ml

What is Bac-Water?

Bac-Water is the short form commonly used in the laboratory supply trade for bacteriostatic water. It is not a peptide but a solvent: water to which benzyl alcohol has been added as a preservative. According to the label, the 10 ml vial contains benzyl alcohol at a concentration of 0.9 %, which corresponds to 9 mg per millilitre. The product has no biological target.

Composition

• Water: H2O, 18.015 g/mol, CAS 7732-18-5
• Benzyl alcohol: C7H8O, 108.14 g/mol, CAS 100-51-6, proportion according to the label 0.9 %

As a mixture, bacteriostatic water has no CAS number and no molar mass of its own.

Role in the laboratory

In the laboratory, bacteriostatic water serves as a solvent for bringing lyophilised research peptides such as Semax or the GLOW Stack into solution. The benzyl alcohol inhibits the growth of bacteria, so that an opened vial can be drawn from several times. This additive is no substitute for aseptic technique. As the benzyl alcohol becomes part of the final solution, it should be established before an experiment begins whether it is compatible with the assay in question. The basics are summarised in the Reconstitution & Storage section.

Handling in the laboratory

Keep the vial closed and protected from contamination. The stopper is disinfected before each withdrawal, and only sterile single-use equipment is used to draw from the vial. Noting the date of first opening on the label makes documentation easier. Notes on storing the peptides themselves are given in the guide Storing lyophilised peptides; further laboratory accessories can be found in the Accessories category.