Special Issues-03-01-2017

A new peptide mapping method was developed specifically for mAb characterization that employs optimal enzyme pH for robustness, but with short digestion times and time-course elements to minimize and monitor deamidation–isomerization, respectively, enabling a more accurate assessment of potential CDR sequence liabilities.

When adhering to sound analytical principles, the inclusion of mass spectrometry in the clinical laboratory can lead to accurate, selective, and precise quantitative methods by detecting new classes of compounds with greater efficiency and sensitivity than is possible with older, established technologies.

A brief preview of this year’s ASMS conference, taking place June 4–8, 2017, in Indianapolis, Indiana.

With this method, a single injection was sufficient to characterize the amino acid sequence with complete sequence coverage. In addition, glycosylation and drug-loaded peptides could be identified from MS/MS spectra. A drug-loaded peptide fragmentation mass spectra study yielded drug-specific fragments, which reinforced the confidence about the identifications. The results reveal the ability of the sheathless CZE–MS/MS method to characterize an ADC’s primary structure in a single experiment.

The isotopic profile of a material refers to the ratios of the stable isotopes of elements contained within, such as 2H/1H, 13C/12C, and 18O/16O. Biological, chemical, and physical processes cause variations in the ratios of stable isotopes; analysis of a material for its distinctive isotopic signature can thus be used to reveal information about its history. Isotope ratio mass spectrometry (IRMS) is a technique used to measure the relative abundance of isotopes in materials. Forensic investigators have used IRMS to measure a variety of materials, such as drugs, explosives, food, and human remains. In a recent web seminar, Lesley Chesson, the president of IsoForensics, Inc., explained how IRMS works and discussed the use of IRMS in forensic science, illustrating her discussion with several case examples.

Click the title above to open the March 2017 issue of Current Trends in Mass Spectrometry, Volume 15, Number 1, in an interactive PDF format.