Mass Accuracy
Mass Accuracy — The degree to which a measured mass matches the true molecular mass, expressed in parts per million (ppm) in high-resolution mass spectrometry.
What Is Mass Accuracy?
Mass accuracy is the difference between the measured and theoretical molecular mass of a peptide, expressed in parts per million (ppm) or daltons. High mass accuracy (< 5 ppm) is essential for confident peptide identification, distinguishing isobaric modifications, and confirming synthetic peptide identity.
Instrument Performance
- Orbitrap: 1-3 ppm. Current gold standard for peptide identification
- Q-TOF: 2-5 ppm. Good compromise of speed and accuracy
- Triple quad: 50-200 ppm. Used for targeted quantification, not high-accuracy ID
- Significance: 1 ppm on a 1,000 Da peptide = ±0.001 Da mass tolerance
Frequently Asked Questions
What is Mass Accuracy?
The degree to which a measured mass matches the true molecular mass, expressed in parts per million (ppm) in high-resolution mass spectrometry.
Why is Mass Accuracy important in peptide research?
Mass Accuracy is a fundamental concept in analytical as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.