Development and characterization of cIEF-MALDI-TOF MS for protein analysis.

This paper describes the hyphenation of cIEF and MALDI-TOF MS via a fractionation or spotting device. After focusing in cIEF the compounds are hydrodynamically mobilized and deposited on a MALDI target plate using a sheath liquid interface, which provides the catholyte solution and the electrical ground. From previous experiments, sample conditions that resulted in a high resolution in cIEF and acceptable protein signal intensity in MS were selected [Silvertand et al.

Recent developments in capillary isoelectric focusing.

The developments in capillary isoelectric focusing (cIEF) over the period 2003-2007 are reviewed. With the focus on technological aspects, cIEF papers published in the fields of methodology, new techniques, detection, multidimensional systems, miniaturization and applications are summarized. The methodology section covers recent research in ampholytes composition, detergents and other additives, carrier ampholyte free cIEF, coatings and other capillary modifications.

Improved repeatability and matrix-assisted desorption/ionization - time of flight mass spectrometry compatibility in capillary isoelectric focusing.

Low repeatability of migration time, peak area, and linearity (pI vs. mobilization time) is a problem often encountered in capillary IEF (cIEF) and is mainly caused by protein precipitation and protein-wall interactions. In order to study the influence of these phenomena, the effect of different classes of additives on repeatability of migration time, peak area and linearity of a mixture of seven model proteins has been investigated.

Selective protein removal and desalting using microchip CE.

This paper describes the on-line sample pretreatment and analysis of proteins and peptides with a poly(methylmethacrylate) (PMMA) microfluidic device (IonChip). This chip consists of two hyphenated electrophoresis channels with integrated conductivity detectors. The first channel can be used for sample preconcentration and sample clean-up, while in the second channel the selected compounds are separated.

Simultaneous quantification of fludarabine and cyclophosphamide in human plasma by high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry.

Fludarabine and cyclophosphamide are anticancer agents mainly used in the treatment of hematologic malignancies. We have developed and validated an assay using high-performance liquid chromatography (HPLC) coupled with electrospray ionization tandem mass spectrometry for the quantification of fludarabine in combination with cyclophosphamide in human heparin and human EDTA plasma. Sample pre-treatment consisted of a protein precipitation with cold acetonitrile (-20 degrees C) using 250 microL of plasma.