Bacteriostatic Water Handling Protocol

Bacteriostatic water (BAC water) is sterile water containing 0.9% benzyl alcohol as a bacteriostatic preservative. The benzyl alcohol inhibits bacterial growth, allowing the vial to be used for multiple entries over its shelf life. This is distinct from sterile water for injection (SWFI), which contains no preservative and must be discarded after a single use. For peptide reconstitution, bacteriostatic water is strongly preferred because reconstituted peptides are typically used over multiple days.

Before first use, visually inspect the bacteriostatic water vial. The solution should be perfectly clear and colorless. Check for particulate matter by holding the vial against a light source and gently inverting it. Verify the vial seal is intact — the aluminum crimp cap should be tight with no gaps, and the rubber stopper should be flush. Check the expiration date printed on the vial or box.

Put on powder-free nitrile gloves. Remove the plastic flip-cap from the vial to expose the rubber stopper. Swab the rubber stopper thoroughly with a fresh 70% isopropyl alcohol swab. Allow the alcohol to air dry completely (approximately 30 seconds). The vial is now ready for needle entry.

Use a fresh, sterile syringe for each draw. Insert the needle through the center of the rubber stopper at a 45-90 degree angle. To prevent creating a vacuum (which makes drawing difficult), first inject a volume of air equal to the amount of water you plan to withdraw. Then invert the vial and draw the desired volume. Remove air bubbles by tapping the syringe barrel and pushing them back into the vial.

Transfer the drawn bacteriostatic water to the peptide vial following the Peptide Reconstitution Protocol. Key reminders: inject slowly down the inner wall of the peptide vial (never directly onto the powder), allow the peptide to dissolve naturally without shaking, and verify solution clarity before use.

After use, leave the rubber stopper in place (do not remove it). Store the bacteriostatic water vial at controlled room temperature (20-25°C / 68-77°F). Keep it upright in a clean, dry area away from direct sunlight. Do not refrigerate unless specified by the manufacturer. Once opened (first needle puncture), bacteriostatic water is typically considered usable for 28 days.

Maintain a log of bacteriostatic water usage: vial lot number, date opened, volume remaining, and expiration date. This ensures you always have sufficient supply and never use expired product. Order replacements before your current supply reaches the 28-day post-opening limit or runs out.