Intact Molecular Weight (MW)
For all compound classes, from small organic molecules to intact glycoproteins, the intact molecular weight is a key characteristic in its identity. Mass spectrometry offers accuracy of measurement over a wide molecular weight range, with minimal, often sub-picomole, sample consumption. Furthermore, any difference between theoretical and measured mass may be indicative of potential modifications.
Experience, and our wide range of mass spectrometry instruments, allows M-Scan to choose the most appropriate ionisation technique for the compound, from MALDI-MS, FAB-MS or ES-MS to an LC-MS experiment for complex mixtures. At higher resolution, measurement of molecular weight to within a few ppm, often to four or five decimal places by 'accurate mass measurement', can aid elucidation of the elemental composition of a compound.
Size exclusion chromatography and SDS-PAGE electrophoresis are also available at M-Scan as alternative techniques to estimate molecular size.
Molecular weight analysis is a key part of the ICH Q6B guidelines for characterisation and confirmation of biopharmaceuticals in support of new marketing applications.

