Mass Spectrometry and Molecular Detection
Mass spectrometry is one of chemistry’s most powerful methods for detecting molecules by transforming them into ions and measuring their mass-to-charge behavior. This article explains how ionization, mass analyzers, detector response, isotope patterns, fragmentation, chromatography coupling, calibration, and spectral libraries support molecular detection and chemical identification. It distinguishes detected features from confirmed compounds, showing why exact mass alone is not definitive evidence of identity. The article surveys electron ionization, electrospray ionization, MALDI, quadrupoles, time-of-flight instruments, ion traps, Orbitrap systems, tandem MS, GC-MS, and LC-MS. With mathematical framing, Python and R workflows, and a full GitHub code scaffold, it presents mass spectrometry as a rigorous evidence system for molecular detection, quantification, and reproducible analytical chemistry.









