How do I work out how much bacteriostatic water to add for a 5mg peptide vial?

Posted by fasted_scientist in Beginner Questions - 1 points, 0 comments.

Hey folks, I’m totally new to this and trying to figure out the basics. I got a 5mg vial of a peptide and the protocol just says add bacteriostatic water but doesn’t say how much. I’m a bit lost on the maths – do I aim for a certain concentration like 1mg/ml or does it depend on what dose I plan to use?

I tried eyeballing it once and ended up with a solution that felt way too thick to draw into a syringe, which made me worry I’d messed up the sterility. Could someone walk me through a simple example, maybe using a 1mg/ml target, and show how to calculate the water volume? Also, is it okay to use a regular insulin syringe for measuring the water, or should I stick to a dedicated mixing syringe?

Any tips on avoiding bubbles or making sure the peptide fully dissolves would be really appreciated. Ngl I’m feeling a bit nervous about getting this wrong, so a straightforward, step‑by‑step explanation would help a lot.

Community discussion - research and educational context only. Not medical advice.