Comparison of ZIC-HILIC and graphitized carbon-based analytical approaches combined with exoglycosidase digestions for analysis of glycans from monoclonal antibodies.

Two LC approaches for analysis of therapeutic monoclonal antibodies (MAbs) are presented and compared. In the first approach, zwitterionic-type hydrophilic interaction chromatography (ZIC-HILIC) of 2-aminobenzamide-labelled glycans was coupled with fluorescence or electrospray ionisation mass spectrometric (ESI-MS) detection. The ZIC-HILIC method enabled relative quantification and identification of major glycan species.

Zwitterionic-type hydrophilic interaction nano-liquid chromatography of complex and high mannose glycans coupled with electrospray ionisation high resolution time of flight mass spectrometry.

In this study we describe a new method for rapid and sensitive analysis of reduced high mannose and complex glycans using zwitterionic-type hydrophilic interaction nano-liquid chromatography (nano ZIC-HILIC, 75 μm I.D.×150 mm) coupled with high resolution nanoelectrospray ionisation time of flight mass spectrometry (nano ESI-TOF-MS).

Glycan profiling of monoclonal antibodies using zwitterionic-type hydrophilic interaction chromatography coupled with electrospray ionization mass spectrometry detection.

We present a new method for the analysis of glycans enzymatically released from monoclonal antibodies (MAbs) employing a zwitterionic-type hydrophilic interaction chromatography (ZIC-HILIC) column coupled with electrospray ionization mass spectrometry (ESI-MS). Both native and reduced glycans were analyzed, and the developed procedure was compared with a standard HILIC procedure used in the pharmaceutical industry whereby fluorescent-labeled glycans are analyzed using a TSK Amide-80 column coupled with fluorescence detection. The separation of isobaric alditol oligosaccharides present in monoclonal antibodies and ribonuclease B is demonstrated, and ZIC-HILIC is shown to have good capability for structural recognition.

Bismuth film electrode for anodic stripping voltammetric determination of tin.

The bismuth film electrode (BiFE), in combination with anodic stripping voltammetry, offers convenient measurement of low concentrations of tin. The procedure involves simultaneous in situ formation of the bismuth film electrode on a glassy carbon substrate electrode, together with electrochemical deposition of tin, in a non-deaerated model solution containing bismuth ions, catechol as complexing agent and the metal analyte, followed by an anodic stripping scan. The BiFE is characterized by an attractive electroanalytical performance, with two distinct voltammetric stripping signals corresponding to tin, accompanied with low background contributions.