Angus
I've finally had the occasion to review the MS and the UPHLC on the "GH"
My first concern is the HUGE discrepancy between the sample you analyzed and rHGH. For example while the "Fisher" product has a MEASURED molecular weight of 22145 amu the "Northern Trusts weight is 22219 amu.
Based on MULTIPLE analyses of rHGH the exact weight is 22126.0463 amu. Now based on my calculations the difference is HUGE (Fisher +19 & Northern Trust +93 !!!) and totally inconsistent with GH.
Moreover the fragmentation array reveals MANY other ions with MW considerably higher than the predominant ion or "GH" in this instance.
What this implies is the base ion is NOT the molecular ion at all but rather one of several larger ions which were not thoroughly analyzed and underwent fragmentation into the more abundant "GH" ion, OR there is a remarkable degree of organic contamination present in the sample selected.
This is particularly important because excluding the rare occurrence of molecular dimers or aggregates, performing MS on any organic molecule should NOT generate ions of a LARGER MW then the PARENT molecule (they undergo fragmentation of varying degrees) GH in the instance.
Furthermore because the summation of those ions whose MW is GREATER than the base peak ("GH"), roughly 30%, your calculation the Northern Trust purity approximates of 90% overly generous to say the least.
Which brings me to the UHPLC. There are clearly two predominant base peaks, one at time 4.47 and the other at 4.69 and several other peak undulations between 4.69 and roughly 6.5 minutes.
These differing base peaks indicate TWO substances with variform molecular weights. In fact because the interval between time 4;16 to 6.5 can NOT be differentiated (isolated into specific peaks) with any degree of certainty additional elusions should have been conducted (if theory were not) and those results depicted, indicating which base peak was used for the Mass spec analysis.
Finally after reviewing the "net" for the various "GENERIC" suppliers of Mass Spec
I noted essentially every one had MW between 0.5-1% ABOVE the known amu
rHGH. Now why is this so unusual? Because such a remarkable discrepancy negates the possibility these GENERIC GH PRODUCTS are legit GH, IMO!
Angus like yourself I'm always concerned (actually I get pretty damn pissed) when some mate, especially one from Meso, is being screwed by another unscrupulous UGL and try my best to stop such activity whenever possible. Let me know your insightful thoughts at your leisure.
Regards
JIM
I've finally had the occasion to review the MS and the UPHLC on the "GH"
My first concern is the HUGE discrepancy between the sample you analyzed and rHGH. For example while the "Fisher" product has a MEASURED molecular weight of 22145 amu the "Northern Trusts weight is 22219 amu.
Based on MULTIPLE analyses of rHGH the exact weight is 22126.0463 amu. Now based on my calculations the difference is HUGE (Fisher +19 & Northern Trust +93 !!!) and totally inconsistent with GH.
Moreover the fragmentation array reveals MANY other ions with MW considerably higher than the predominant ion or "GH" in this instance.
What this implies is the base ion is NOT the molecular ion at all but rather one of several larger ions which were not thoroughly analyzed and underwent fragmentation into the more abundant "GH" ion, OR there is a remarkable degree of organic contamination present in the sample selected.
This is particularly important because excluding the rare occurrence of molecular dimers or aggregates, performing MS on any organic molecule should NOT generate ions of a LARGER MW then the PARENT molecule (they undergo fragmentation of varying degrees) GH in the instance.
Furthermore because the summation of those ions whose MW is GREATER than the base peak ("GH"), roughly 30%, your calculation the Northern Trust purity approximates of 90% overly generous to say the least.
Which brings me to the UHPLC. There are clearly two predominant base peaks, one at time 4.47 and the other at 4.69 and several other peak undulations between 4.69 and roughly 6.5 minutes.
These differing base peaks indicate TWO substances with variform molecular weights. In fact because the interval between time 4;16 to 6.5 can NOT be differentiated (isolated into specific peaks) with any degree of certainty additional elusions should have been conducted (if theory were not) and those results depicted, indicating which base peak was used for the Mass spec analysis.
Finally after reviewing the "net" for the various "GENERIC" suppliers of Mass Spec
I noted essentially every one had MW between 0.5-1% ABOVE the known amu
rHGH. Now why is this so unusual? Because such a remarkable discrepancy negates the possibility these GENERIC GH PRODUCTS are legit GH, IMO!
Angus like yourself I'm always concerned (actually I get pretty damn pissed) when some mate, especially one from Meso, is being screwed by another unscrupulous UGL and try my best to stop such activity whenever possible. Let me know your insightful thoughts at your leisure.
Regards
JIM
