Mass spec testing question

[fightingfires]

Is it LC Mass spec testing that we are after when testing our compounds?

I only ask because there is ESI Mass Spec, GC Mass Spec etc

thanks guys

 

[lightspan]

Is it LC Mass spec testing that we are after when testing our compounds?

I only ask because there is ESI Mass Spec, GC Mass Spec etc

thanks guys

Mass spec can determine the identity of the compound in your gear. HPLC determines concentration, when run against a known pure standard of the compound of interest. Some mass spec techniques, used alone, can give a purity estimate, but it is only an estimate. That estimate is based on total ion count.

Gold standard is combined HPLC-MS. It gives compound identity and purity.

GC is only useful for compounds that are relatively volatile and won't degrade when heated. Steroids are not particularly volatile, and degrade when heated to typical column temperatures used in GC.

 

[lightspan]

A typical scenario for a total unknown: run MS with a "soft" ionization technique to determine what compound(s) is/are in the vial. Then run a calibration curve with a standard (pure compound of interest) on HPLC. Run the unknown, and determine purity of the compound of interest. There are several ways to do it, any precise determination requires chromatography and mass spec.

 

[fightingfires]

@lightspan any chance I could pm you a question regarding tests? I just do not want to order an incorrect or partial test.

 

[mercury]

About 10 years ago there was a lab in Colorado, they used old Agilent HP 1090 (HPLC)

It was calibrated only to detect specific steroid and measure the potency. It can detect everything but is has to be calibrated first.

HPLC/MS is designed this way that it will show you everything inside but like HPLC it has to be calibrated to show you also the potency.

The lab in Colorado closed doors long time ago after FDA when after labs testing steroids for public.

HPLC stand for high pressure liquid chromatography
GC stands for gas chromatography.

Both can be used to detect steroids and measure the potency.

 

[fightingfires]

I have both pharma-grade Test E 200mg/ml and also homebrewed from chinese pwd Test E at 200mg/ml
I mainly want to know if the chinese powders purity is.

So I can send a sample of each for comparison...just not sure of the exact tests

 

[apmakeio]

About 10 years ago there was a lab in Colorado, they used old Agilent HP 1090 (HPLC)

It was calibrated only to detect specific steroid and measure the potency. It can detect everything but is has to be calibrated first.

HPLC/MS is designed this way that it will show you everything inside but like HPLC it has to be calibrated to show you also the potency.

The lab in Colorado closed doors long time ago after FDA when after labs testing steroids for public.

HPLC stand for high pressure liquid chromatography
GC stands for gas chromatography.

Both can be used to detect steroids and measure the potency.

HPLC mobile phase and stationary phase (column) need to be adjusted according to the chemical targeted for analysis. That takes few minutes for a qualified engineer. After MS reveals the MW the engineer can then adjust the column and mobile phase, there are also tons of resources regarding testing practices over anabolic steroids. Not complicated at all!.

However, I'd be interested in @mercury defining "potency". What do you understand by "potency" and how is it analyzed? You seem to give the definitions for HPLC and GC but include in your posts nonexistent terms.

 

[mercury]

However, I'd be interested in @mercury defining "potency". What do you understand by "potency" and how is it analyzed? You seem to give the definitions for HPLC and GC but include in your posts nonexistent terms.

potency is common language used on forums to describe the strenght of gear.

so if your vial is indeed 250 mg/ml you call it potent.

term "Quantitative analysis" are not used because not everybody has clue what it means.

 

[apmakeio]

potency is common language used on forums to describe the strenght of gear.

so if your vial is indeed 250 mg/ml you call it potent.

term "Quantitative analysis" are not used because not everybody has clue what it means.

That's purity assay.

 

[lightspan]

That's purity assay.

Easy, killer, he's clearly not a native English speaker. Semantics are not worth a pissing match. Read what he wrote, in context he is referring to purity determination.

 

[apmakeio]

Easy, killer, he's clearly not a native English speaker. Semantics are not worth a pissing match. Read what he wrote, in context he is referring to purity determination.

Its not about semantics its about the fact that this type of term confusion can lead to misleading information. "Strength / Potency" are related to the pharmacological value of the drugs and are to be analyzed by bio-equivalence studies. When it comes to analytic testing its either qualitative (identification) or quantitative (purity, weight). Its better to clear things up and put them on the right track than keep repeating misleading terms.

 

[mercury]

let's leave the terms for chemistry forum and talk the easy language for everybody to understand here.

Because nobody cares if I use FDI detector or hook up MS to my CG or which column.
This is just nonsense talk here. Of if I use ChemStation or Empower software.

What people care is the potency, which means here strength in mg/ml.

 

[fightingfires]

I just am inquiring to a lab to test for me. I am a trt patient with a valid script for Test enanthate so hopefully they can test at least this one compound for me if I provide them with the documents showing I am in compliance with the law in having this compound.

(providing they agree) I can send them a pharma sample of test E and a second homebrewed one from Chinese raws (also Test E) to compare to. This will at least give me an idea on how far off they are on the potency of that particular chinese powder.

This from the labs website.......

LC Mass Spec
Liquid chromatography-mass spectrometry

Our main tool for LC-MS services is a Waters/Micromass Quattro triple quadrupole tandem mass spectrometer. The separation front end we use is an Agilent HPLC systems for applications requiring analytical (0.1-1 ml/min) flow. For nano-flow applications we use a LC Packings/Dionex LC system with 2D capabilities.

Liquid Chromatography Mass Spectrometry (LC/MS) is an analytical technique for identification, quantitation and mass analysis of a wide variety of non-volatile or semi-volatile compounds in a mixture. This technique also allows for the structural elucidation of unknown molecules through fragmentation.

 

[apmakeio]

Just tell them what you're trying to determine and they'll suggest you the analytical solution. Post it up here as I think can be usefull for other people interested in inquiring lab testing services.

 

[fightingfires]

I'll do just that apmakeio. Hopefully they will not shy away from the testing either.
I'd imagine it will be a couple days before I get a reply

 

[Dr JIM]

That's purity assay.

'
Excellent point mate!

The fact is AAS potency is a BIOLOGIC study that compares the A/A ratio! Most of, if not all of these studies have already been conducted (excluding some research grade or "designer" AAS) and used the comparative hypertrophic effects of a particular AAS on either the prostate gland or select voluntary skeletal muscle such as the anal sphincter in RATS.

That's right almost all of the "potency" data was derived from rat studies BUT we've come to learn over the past 50 some odd years the data is/was actually quite accurate when applied to humans.