Log in
Register|
pmgjoshi ☆ India, 2009-04-13 11:40 (6287 d 17:37 ago) Posting: # 3514 Views: 3,488 |
|
|
Dear all, I have done one study in which the lable claim of the Drug tablet is of Bivalent salt of Zolpidem (Zolpidem Tartarate). For the preparation of stock solution I have considered Monovalent molecular weight. The analysis was done on HPLC (with UV detector). 1. The counterpart (sponsor) is asking us to consider the bivalent molecular weight. But as per the FDA recommondations parent ion should be measured and we have done the same. So, what is the right method? 2. This was the case with the UV-HPLC as a detector. If it would have been LC-MS/MS, as per the basics of Mass spectometry I had to consider actual molecular weight of the Monovalent. So, should we consider Monovalent weight irrespective of the analytical technique? Best regards, Prashant |
|
babun14 ☆ 2009-04-14 12:55 (6286 d 16:22 ago) @ pmgjoshi Posting: # 3520 Views: 2,768 |
|
|
Dear Prashant, You should consider the no. of free analyte present in the salt for the calculation purpose. So, in this partcular case the conc. would be double to what you have used for quantification purpose. The formula for conc. is =(amount of salt weighed/total volume )*(mol. weight of free analyte/Mol. wt. of salt)*no. of free analyte Hope this will help you. regards Bani -- Edit: Full quote removed. Please see this post! Helmut |
|
pmgjoshi ☆ India, 2009-04-16 09:13 (6284 d 20:03 ago) @ babun14 Posting: # 3543 Views: 2,712 |
|
|
Dear Bani, Thanks you soo much..  |
Ing. Helmut Schütz