It just isn't feasible, since a 10% BA solution can't be created at room temperature. The most you can realistically reach is around 4%.eidos said:
BBA1969 said:
Did you mean 0.1ml into 10ml (or 1ml into 100ml)?eidos said:
BBA1969 said:
€1 for a single ml
DrPepr's advice is the right one - brew your own.
Here's the Benzyl I use:
View attachment 270
For the water side of things, ask for "Braun Aqua Pro Inj." or "Aqua Sterop" and take the 50ml size. Just don't accidentally buy the saline (NaCl) one. Prices run €2.20 to €3.25 per 50ml vial before shipping.
That works out under €4 for 50ml of BAC. Anything still sitting there past 2 months, bin it. At those prices you could bin it after a month and not care.
Method: add 0.5ml of benzyl per 50ml vial and you're good to go.
What I do is make up a 10% BA stock in sterile water first. Then 1 ml of that stock goes into 10 ml of sterile water, which lands the concentration at 0.91% v/v. Ordinary sterile water ampules are all I need for it. Less waste that way.
Lab practice is generally the reverse - solvent gets added until you hit the target volume. It's more exact, but for our peptides that precision buys you nothing. All we actually need is to sit somewhere between 0.8% and 1.5%. In any case, my kit won't do any better.
I did consider the 10ml plastic "flapule", but it struck me as more faff than it's worth. Extra work, a tinier dose of Benzyl, more vials, more syringes and so on..
As it stands I use 1 large 50ml vial, a single 0.5ml syringe and an alcohol swab, and I'm set for more than a month.
Being able to buy the sterile water in 30ml glass vials would be nicer still, since there'd be less waste.
Mixing a 10% Benzyl Alcohol Stock Solution
1. draw 1ml out of a 10ml vial of sterile water (the plastic Aqua ones work fine)
2. put 1ml of USP BA 99.95% into the 9ml of water
You now have 10 ml of 10% stock BA (store it in a 10ml sterile vial)
Mixing a solution at ~ 0.9% Benzyl Alcohol
1. put 1ml of the 10% stock BA into a sterile vial
2. top it up with 10ml of water
That gives a BA concentration of ~ 0.91% (1/11)
If the vial can't take 11 ml, fill it with as much water as you can without the level touching the septum. The concentration then lands somewhere between 0.91% and 1% (by all accounts it still doesn't sting at that strength).
Label every vial, no exceptions.
For those attempting to mix their own, the practical outcome is that a good amount will remain undissolved, yet it's hard to spot because it may resemble air bubbles. A quick stir alone won't get BA to dissolve.