IsoTopics™ – November 2015

Investigations into the regulation of the N-linked glycome by cancer and disease demands rigorous quantitative methods afforded by stabie isotope labeling and identification given by the specificity of mass spectrometry. N-linked glycans present challenges to MS because of the complexity of their structures (MS/MS or MSⁿ required), hydrophilicity, and low abundance. Learn more...

To assist in the standardization of multiple reaction monitoring-mass spectrometry (MRM-MS) for clinical proteomics, a biomarker assessment kit (BAK-76) has been developed for the precise quantitation of 76 high-to-moderate-abundance proteins, which spans a plasma concentration range of >4 orders of magnitude. 

Metabolic isotopic analysis (MIA) utilizes stable isotope-enriched substrates and mass spectrometry to study metabolism in living cells and tissue. Because isotope-labeled substrates make the determination of metabolic pathways and flux in living cells or tissue possible, MIA has become an integrated platform in oncology research.

Looking to increase the data quality and output of your ¹³C tracer study? This paper reviews key aspects of experimental design and data interpretation when utilizing ¹³C labeled tracers to interrogate cellular metabolism. Topics include: a comparison of metabolic steady state and isotopic steady state, labeling patterns of metabolites and cellular compartments, and labeling for steady state and dynamic studies.  

Mass spectrometry as a routine tool in the clinic is becoming more and more of a reality every day, presenting numerous opportunities in the field of proteomics. This review provides a comprehensive overview of existing LC-MS bottom-up proteomic techniques, as well as the potential for future approaches using intact protein quantification. It includes a comparison between the two approaches, the limitations of both, and some of the hurdles that will need to be overcome for successful detection.

by Don Chace

1. Proven in the field. CIL developed the first sets of internal standards for MS/MS quantification in the 1990s with the primary developers of the technology used in screening.  

2. CIL standards have been an essential component of NBS lab protocols and methods used to screen millions of infants.