Agilent Manuals

This Application Note illustrates the potential of combining protein depletion using the Agilent Multiple Affinity Removal System and protein or peptide fractionation using the Agilent 3100 OFFGEL Fractionator for the LC-MS based analysis of plasma proteins.

This is an application note that describes a protein profiling approach that combines accurate mass ESI-TOF data with differential analysis to highlight and identify putative biomarkers.

Here, we present a novel and highly robust method for the separation and identification of HeLa cell membrane proteins by an LC-only based separation strategy. Employing optimized reversed phase (RP) conditions and using a uniquely designed reversed-phase column material specifically engineered to enable high efficient separation of membrane proteins, the results demonstrate that this approach allows high identifications of membrane proteins.

This document illustrates the effectiveness of the Agilent 3100 OFFGEL Fractionator for the prefractionation of complex protein or peptide mixtures. The tryptic digest of E. coli proteins was fractionated into 24 fractions, and peptides were identified using reversed phase liquid chromatography with mass spectrometric detection. The distribution of peptides and their isoelectric points in each fraction was analyzed. The results show efficient peptide fractionation and improved protein identification using the Agilent 3100 OFFGEL Fractionator.

This is an application note that describes a high recovery HPLC method for the identification of human brain lipid raft membrane proteins based on a macroporous reversed-phase column.

This note describes the characteristics and importance of protein phosphorylation, as well as the method of qualitative analysis of protein phosphorylation using HPLC-Chip electron transfer dissociation ion trap mass spectrometry technology. By comparing the differences between collision-induced dissociation (CID) and electron transfer dissociation (ETD) mass spectrometry techniques, it demonstrates the ability to analyze samples using both CID and ETD in the same LC/MS run. Examples of the identification of site-specific phosphorylation using an Agilent HPLC-Chip system are provided.

This Application Note demonstrates how Intelligent Sample Loading automates and optimizes sample enrichment on the HPLC-Chip, and also shows how Intelligent Sample Loading increases the number of peptides detected in a protein digest test mixture.

This article introduces several label-free methods for the relative quantitation of proteins. These methods include comparing the mean peak area of all peptides identified for a protein in each sample, the peak area of a peptide found in both samples, the number of identified peptides in each sample, and the number of spectral hits in each sample.

This application note describes how to use the Agilent 1200 Series Rapid Resolution LC system and Agilent ZORBAX Rapid Resolution High Throughput columns to separate compounds in complex samples, how to calculate the empirical formula of unknown compounds from high mass accuracy data acquired with the Agilent 6210 time-of-flight and teh Agilent 6510 Q-TOF mass spectrometer, how to use the Agilent MassHunter Profiling software to quickly and computer-assistedly analyze complex mass spectrometry data, and how to use the Agilent MassHunter Profiling software to analyze the differences in related samples in different applications.

This Application Note describes the quantitative analysis of carbohydrates in fruit juices. The analysis technique deployed the Agilent 1200 Series evaporative light scattering detector, which proved to be a viable alternative to refractive index detection because of lower susceptibility to temperature fluctuations and the possibility to perform gradient analyses. Correlation coefficients greater than 0.99 were achieved for the carbohydrates glucose, fructose, sucrose and sorbitol.

An LC/MS method was developed to monitor several coumarin rodenticides in complex matrices.

This application describes a method for analyzing intact triglycerides by LC/MS and the type of information available.

Four commercial natural colorants – red cabbage, Monascus, paprika, and lac – were analyzed using ESI and APCI-LC/MS. The MS data provided molecular weight information and some structural information for the major components in these pigments.

This document describes an alternative to 2D gel electrophoresis based on isoelectric point OFFGEL electrophoresis and high-sensitivity on-chip protein detection using the Agilent 2100 bioanalyzer.