Special Issues-03-01-2010
A Study of Matrix Effects on Multiply Charged Compounds
March 1st 2010In preclinical development, the absolute quantification of peptides in biological matrices becomes a challenge due to the limited availability of stable label internal standards and affinity-based cleanup. This puts a renewed emphasis on matrix effects, especially for the bioanalysis of hydrophobic peptides. While the impact of matrix effects has been studied for extensively singly charged small molecules, their effect on multiply charged compounds has yet to be characterized fully. This article discusses initial results from matrix effect experiments in relation to the bioanalysis of hydrophobic peptides and techniques used to minimize matrix effects.
Advances in TOF-MS-Based Screening for Food Safety Residue Analysis with a Positive Approach
March 1st 2010Mass spectrometry plays an increasingly significant role in the analysis of residues and contaminants in food. Here we will illustrate how the combination of ultrahigh-pressure liquid chromatography (UHPLC) and high-resolution time-of-flight-mass spectrometry (TOF-MS) is used to generate a screen of veterinary drug residues in products of animal origin. The use of UHPLC–TOF-MS and dedicated, workflow directed software allows rapid screening for large numbers of residues and automated quantification of positive samples. In addition, we illustrate how the data generated using MSE acquisition mode enable critical structural information to be collected, which offers additional selectivity and confirmatory data for compound identification and facilitates elucidation of the structure of newly discovered compounds.
Comprehensive Characterization of Monoclonal Antibodies Using a Microfluidic Chip-Q-TOF Platform
March 1st 2010Accurate, sensitive, and comprehensive characterization of monoclonal antibodies is an absolute necessity to the pharmaceutical and diagnostic industries to meet regulatory requirements and ensure the efficacy and safety of the final product. Microfluidic chip-based high performance liquid chromatography technology interfaced with the mass accuracy of quadrupole time-of-flight mass spectrometry provides the ability to rapidly and efficiently assess the quality of intact monoclonal antibodies, confirm their amino acid sequence, and determine their glycosylation state, while consuming very small amounts of these precious products.
