Simple GC calculation help

Discussions about GC and other "gas phase" separation techniques.

4 posts Page 1 of 1
I have a method for GC-MS all set up and ready to GO.

I have made a calibration curve of 5,10,20 and 30ppm of Compound A.

Each standard is made as follows:

Using 2000ppm stock solution of standard of compound A.

0.125ml into 50ml = 5ppm
0.250ml into 50ml =10ppm
0.5ml into 50ml = 20ppm
0.75ml into 50ml = 30ppm.

Sample made as follows:

50mg of ‘Sample’ into 50ml and run against the standards

I what to calculate ‘Compound A’ from the 50mg ‘sample’

What is the calculation to calculate 'Compound A' in the 50mg of sample dissolved in 50ml please?

Sorry for easy question, but I am new to GC-MS and would like to learn more please.

Many Thanks in advance
Your instrument software should give you the concentration of compound A (=x) in the 50mL, and should be between 5-30ppm provided it's within the calibration.

If it doesn't calculate it, you need the peak areas which you plot against the concentration of standards in a program like MS Excel. Apply a fit to obtain a calibration curve. If linear, the curve will give an equation of y=ax+b. Put the sample peak area as y to obtain x.

Now x is the concentration in 50mL (mg/L = ppm). For example 12mg/L. The final result in ppm (mg/kg) sample is 12mg/L * 0.050L/0.000050kg = 12000ppm = 12mg of compound A in 1g sample.
Thank you for you help.

This helps greatly....
Thank you for you help.

This helps greatly....
4 posts Page 1 of 1

Who is online

In total there are 5 users online :: 0 registered, 0 hidden and 5 guests (based on users active over the past 5 minutes)
Most users ever online was 599 on Tue Sep 18, 2018 9:27 am

Users browsing this forum: No registered users and 5 guests

Latest Blog Posts from Separation Science

Separation Science offers free learning from the experts covering methods, applications, webinars, eSeminars, videos, tutorials for users of liquid chromatography, gas chromatography, mass spectrometry, sample preparation and related analytical techniques.

Subscribe to our eNewsletter with daily, weekly or monthly updates: Food, Environmental, (Bio)Pharmaceutical, Bioclinical, Liquid Chromatography, Gas Chromatography and Mass Spectrometry.

Liquid Chromatography

Gas Chromatography

Mass Spectrometry