New Mass Screening Approach for Algal Blooms
October 24th 2017Researchers from The First Institute of Oceanography in Qingdao, China, have developed an exact mass suspect screening approach for identifying multiple lipophilic marine toxins in seawater, suspended particulate matter (SPM), and marine sediment using LC–TOF-MS.
Tips & Tricks: New and Old Approaches to Handle Unknown dn/dc in GPC/SEC-LS
October 10th 2017The intensity of the light scattering signal depends on concentration, molar mass, and the specific refractive index increment, dn/dc, of the sample. dn/dc therefore usually needs to be known to derive molar masses by gel permeation chromatography/size-exclusion chromatography-light scattering (GPC/SEC-LS). How to overcome the issue of unknown refractive index increments is outlined in this instalment of Tips & Tricks. In particular, a new approach to derive molar masses by GPC/SEC-LS that requires only the molar mass of a reference material, and not the dn/dc of the sample or of the reference material, is introduced.
Resolving the Complexity of Biomacromolecules Using Multiple Modes of Chromatography
October 1st 2017To resolve and quantitate monoclonal antibodies and antibody–drug conjugates, analytical scientists need various chromatographic modes, such as sizeexclusion, ion-exchange, hydrophobic interaction, and hydrophilic interaction chromatography. Here, we provide advice for making the most of each mode.
Resolving the Complexity of Biomacromolecules Using Multiple Modes of Chromatography
October 1st 2017Separating proteins and antibodies is a unique analytical challenge because of the complexity of the analytes. Both sample heterogeneity, because of a number of chemical modifications to the analyte, and nonspecific binding to the silica surface often result in chromatographic peak broadening and tailing. This instalment of “Column Watch” focuses on several different chromatographic strategies that analytical scientists can use to resolve and quantitate various biomacromolecules, including monoclobal antibodies (mAbs) and antibody–drug conjugates (ADCs). Selected aspects of size-exclusion, hydrophobic interaction, ion-exchange, hydrophilic interaction, and reversed-phase chromatography are discussed.