Hi Dartin, I think better solution is dissolves in 0.9% saline which is compatible with the animal and will not be toxic, since insulin is also easily dissolved.

Is there a reason why you're not using liquid regular insulin? This is what we used for injection in mice and rats.

Hi Dartin, I think better solution is dissolves in 0.9% saline which is compatible with the animal and will not be toxic, since insulin is also easily dissolved.

I would like to say saline. Normally when you say in humans 0.9% (NaCl) but maybe it would be best to check if there is anything for rats. I would also suggest a buffer with the same pH. Maybe there could be better. (Acetate, bicarbonate?). Will the insulin be injected in the stomach or i. V (intravenous)? You should make sure the pH is adequate for any of those situations. The form of administration too. ("injection"?) maybe the injection will be i. P (lower side abdomen?).

Hi, Miriane de Oliveira, saline maybe a good choice, we'll consider it, thanks for your suggestion, good luck~

Marie Mortreux , Hi, liquid regular insulin is really a convenient product, without these dissolve procedures, I think we'll choose it primarily next time, would you mind suggesting some liquid insulin product for us, we would appreciate it very much.

Mª Angeles Zorrilla Lopez-Perea Hi, thanks for your suggestion which with many details, this time we decide to dissolve insulin powder in pH2-3 diluted HCl solution, and without adjust pH back to ~7.4, because we searched that the structure and stability of insulin at this pH is normal. Then the insulin will be mixed into saline before injection, according to the amount we need(about 100ul of insulin into 1ml of saline), We thought it would be less toxic for rats considering of the low pH problem.

Hi, we used novo nordisk insulin pen for ip injection at 0.75U/kg (in mice)

Marie Mortreux okay，thanks~

Chrystalline (powdered) insulin will not l to get final concentration accuratlel