ResourceSeparations

Improving Low Abundance Protein Identification in Complex Proteome Samples

24 Jul 2013

NanoLC coupled with nanospray ionization (NSI) MS has become the standard for identification of low abundance proteins in complex proteomics samples. Although this technique provides sensitivity and resolution, the low flow rates used with this technique often result in long sample loading times, long gradient delays and long system re-equilibration times. The MS only generates useful MSMS spectra during the LC gradient time, resulting in MS utilization rates of only 20-50% of the total run time (inject to inject). This application note presents a method to increase the relative MS utilization time without impacting sensitivity or resolution.

Links

Tags

UHPLC and HPLCHigh performance liquid chromatography (HPLC) and ultra high performance liquid chromatography (UHPLC), also known as UPLC, are analytical techniques used to separate, identify and quantitate components of complex mixtures including biological samples such as proteins and lipids as well as chemical mixtures of pesticides, drugs and oils. Both techniques are liquid chromatographic methods but differ by operating pressures (HPLC < 6000 psi < UHPLC ). Components of HPLC and UHPLC systems include columns, detectors, pumps, autosamplers and column heaters. Explore a range of UHPLC and HPLC columns for your specific sample needs including reverse phase, normal phase, ion exchange, HILIC, ion exclusion and size exclusion columns. For more specialized HPLC, explore FPLC, countercurrent LC and simulated moving bed systems. Find the best UHPLC and HPLC equipment in our peer reviewed product directory: compare products, check customer reviews and receive pricing direct from manufacturers.LC-MSLC-MS (liquid chromatography-mass spectrometry) systems and equipment are used for separation and quantitative analysis of complex mixtures, combining liquid chromatography and mass spectrometry. Quantify proteins, contaminants, pesticides or screen for drug metabolites with a high level of sensitivity. LC-MS systems and equipment include reverse phase, normal phase and specialized columns integrated with various MS detectors such as time-of-flight (TOF), quadrupole, orbitrap or ion trap mass analyzers. LC-MS/MS instruments equipped with a qTOF or triple quadrupole analyzer give greater sensitivity and resolving power to your analysis. Find the best LC-MS equipment in our peer-reviewed product directory: compare products, check customer reviews and receive pricing direct from manufacturers.Mass SpectrometryMass spectrometry (MS) is a powerful analytical technique used to identify and quantify molecules based on the mass-to-charge ratio of gas-phase ions. It provides detailed information about the structure, composition, and properties of compounds and is widely used across fields such as environmental monitoring, materials science, drug discovery and development, food and beverage testing, and wider chemical research. Key MS techniques include tandem mass spectrometry (MS/MS), liquid chromatography–mass spectrometry (LS-MS) and inductively coupled plasma (ICP-MS). Choosing from these wide range of techniques and technologies can be a daunting task, so keep up to date with scientific applications, performance expectations, and customer reviews here all in one place. Visit our product directory to receive quotes direct from the manufacturer. ProteomicsProteomics is the systemic bioinformatics study of proteins and amino acids, including their structure, size, function and identification. Tools used in proteomics include chromatography, blotting and gels, protein arrays, mass spectrometry and ELISA and associated analysis software. Analyzers and proteomic systems should be sensitive, high resolution, fast and may be automated for high-throughput.NanoLCNano LC is a nano scale liquid chromatography technique typically used for proteomic applications. The nano refers to the very low flow rate of the mobile phase in the system. The advantage of nanoLC is its high sensitivity. Often the system is integrated with a mass spectrometer in nano LC-MS or nano LC-MS/MS. When using nanoLC equipment consider column choice, software and accurate and precise flow rate control.Protein QuantificationThe detection and quantification of proteins in a sample is vital across life sciences, pharmaceutical research and clinical diagnostics, and a variety of equipment is available to scientists to simplify the workflow. Proteins of interest can be easily labeled and detected on light-based detection instruments. Immunoassay kits allow you to identify a specific protein of interest and protein detection beads or antibody microarrays allow you to identify multiple specific proteins at once. Protein interactions and enzyme activity can also be monitored with protein-protein interaction assays. Additionally, the biophysical characterization of proteins is made easy with biokinetic analyzers. Find the best protein detection and quantification products in our peer-reviewed product directory: compare products, check customer reviews and receive pricing direct from manufacturers.Protein BiologyThe analysis of protein expression, identity and function is vital for many areas of life science research and drug discovery. Some of the most commonly used techniques in protein analysis include Western blotting, electrophoresis and mass spectrometry.
Improving Low Abundance Protein Identification in Complex Proteome Samples