Analytical Answers
1st August 2025
What m/z would be observed in the -ve ion mass spectrum of an oligonucleotide (m.wgt 15324) ionised by -8H +Na?
- 2188.0
- 1917.4
- 2191.3
- 1919.4
And the right answer is:
3. 2191.3
This question was from Colin


Colin, our Technical Support Chemist, is a key member of our Training & Technical Team. He handles a range of responsibilities, including provide technical training and all levels of practical advice in support of any HPLC, GC, MS and SPE related applications.
Would you like to become more knowledgeable on this topic?
You're in the right place!
With years of experience in chromatography and mass spectrometry training, we help customers maximise the performance of their analytical equipment and workflows.
Our training is flexible and designed to fit your needs - whether it's on-site at your lab, in-person at a training centre, live online with expert tutors, or available on demand through our CHROMacademy eLearning platform.


Last week's question - 25th July 2025
SMART Chromatography purifies biomolecules directly from feed streams. Which traditional processing step does it eliminate?
1) Elution
2) Clarification
3) Buffer
4) pH adjustment