Application Notes: Biological, Medical, and Clinical
Enhanced Peptide Identification with an Ultra High Resolution Mass Spectrometer
July 2nd 2010Analysis of biological samples frequently involves the identification of peptides from low amounts of complex samples. Confident identification of these peptides requires rapid generation of high quality, high sensitivity MS and MS–MS data. The maXis TOF mass spectrometer incorporates novel technical innovations, which together produce an unprecedented level of data quality, resulting in a significant increase in the number of peptides identified from challenging samples.
Light Scattering for the Masses Protein–Protein Interactions
July 2nd 2010Over-expression of recombinant proteins is commonly used for the production of protein reagents in industry and academia. Problems often occur relating to the stress put on the cells to deal with this huge increase in synthesis.
On-line SPE-LC of Catecholamines in Urine with Fluorescence Detection
December 2nd 2009Catecholamines are important markers for the diagnosis and management of tumour diseases of the sympathoadrenal system. The major catecholamines are dopamine, norepinephrine and epinephrine. Urine tests have shown to be applicable to measure the level of catecholamines in the human body. Various separation methods have been used for the clean-up of catecholamines in biological fluids: solvent extraction, adsorption on alumina, ion-exchange and solid-phase extraction of a diphenylboronic acid-catecholamine complex. From the point of simplicity, reproducibility and automation the last method is the most suitable and can be realized by on-line SPE–LC. Diphenylborate forms a negatively charged complex with the diol groups of catecholamines. These complexes which are strongly retained on a polystyrene-divinylbenzene cartridge in alkaline medium (pH 8.5) can be eluted in a second step from the SPE unit directly onto the HPLC column. The separation of catecholamines is performed in isocratic mode by..
Comparison of Ion Trap and Q-TOF Mass Spectrometers for Protein Identifi cation
September 1st 2009This study uses the challenging analysis of a complex, multi-organ peptide digest of Caenorhabditis elegans (C. elegans) to compare the performance of a novel linear ion trap mass spectrometer and a quadrupole time-of-flight (Q-TOF) mass spectrometer.
IgG Aggregation Using Online Fluorescent Dye Detection in HP-SEC and AF4
September 1st 2009To guide the development of aggregate free protein formulations, there is an urgent need for formulations, there is an urgent need for complementary methods which allow a sensitive detection, characterization, and quantification of different types of protein aggregates.