Plunge it into the rubberized top of your liquid B12 vial
Unopened BAC water is good until the expiration date printed on the label, which is typically 2 to 3 years from the date it was manufactured
It is shallow, so the needle only travels a short distance, and it has fewer pain-sensitive nerves than deeper tissue, so most people feel a small pinch rather than a deep ache
Reconstitution and Aliquoting Handle this material according to institutional SOPs for weighing, reconstitution, aliquoting, and storage
The rubber stopper is exposed to the open air, and failing to sanitize it is the most common way to introduce bacteria into your sterile solution.
While bacteriostatic water is designed for multiple withdrawals due to its preservative, it can certainly be used for single-use applications