The Application Notebook-09-01-2018

The easy to use, new LipiFiltr® push-through purification cartridge was designed to remove lipids from acetonitrile extracts. This application will outline the performance benefits achieved using the new LipiFiltr® cartridges in applications involving multiclass, multiresidue analysis for pesticides in complex, high fat samples.

Phospholipids (PLs) are the major components of cellular membranes. They are important for the functionality of membrane proteins or serve as precursors for second messengers. Several studies reveal the role of PL alterations in various diseases such as cancer (1). Therefore, it is crucial to identify and quantify PLs in complex biological samples for lipidomic studies and clinical research.

In this study, a fast, sensitive, and selective multiresidue method has been developed by coupling QuEChERS sample preparation with LC–MS/MS. Using time-managed-MRM™ in the QSight® triple quadrupole mass spectrometer, the optimum dwell time can be generated automatically for MRM transitions based on the number of coeluting transitions, expected cycle time, retention time, and tolerance time window of the targeted analytes. Such method automation results in improved data quality and better sensitivity, accuracy, and reproducibility, as demonstrated in this study by the results of 213 pesticide residues analyzed in grape samples.

Abuse of synthetic opioid prescription painkillers such as fentanyl, along with a rapidly growing list of illicit analogues, is a significant public health problem. In this study, we developed a simple dilute-and-shoot method that provides a fast 3.5-min analysis of fentanyl and related compounds (norfentanyl, acetyl fentanyl, alfentanil, butyryl fentanyl, carfentanil, remifentanil, and sufentanil) in human urine by LC–MS/MS using a Raptor Biphenyl column.

The amounts of high- and low-molecular-weight impurities are critical quality attributes for a therapeutic protein. Size-exclusion chromatography (SEC), the standard technology for analyzing aggregation and fragmentation, was applied to elucidate the molecular similarity between an Adalimumab biosimilar antibody and the corresponding innovator product Humira.

This application note describes the determination of pharmaceuticals from serum using solid-phase extraction (SPE) with the hydrophilic-lipophilic balanced SPE phase CHROMABOND® HLB for analyte enrichment and for sample cleanup. The eluates from SPE are finally analyzed by HPLC–MS/MS on a NUCLEOSHELL® PFP core–shell phase

This application note shows the pyrolysis-GC×GC–HRMS profiles of crude oils for more detailed separations and more complete characterization of complex matrices, especially on the speciation of heteroatoms such as sulphur-containing compounds.

SEC-MALS analysis of cellulose provides absolute molar mass distributions to understand the impact of different extraction processes. The biopolymer is solubilized in DMAC, enabling liquid chromatography without degradation.

Chitosans are analyzed by SEC-MALS to determine molar mass moments and distributions.