Knowledge Base Article

Differences between iTRAQ® Reagents Application Kit - Protein (4374321) and iTRAQ® Reagent 4Plex or 8Plex Kits

This article describes the different workflows for the iTRAQ® Reagents Application Kit - Protein (4374321) and the iTRAQ Reagents - 4plex or 8plex kits.

What Is the Exact Mass that iTRAQ® Reagents Add to Peptides?

SCIEX does supply the masses of the labels in the iTRAQ® Reagent 4plex and 8plex kits, but masses with more significant figures can be found at www.unimod.org.

Aliquots of Bulk iTRAQ® Reagent Require Cold Storage Under Inert Gas

When aliquoting bulk iTRAQ® reagent, vials must be stored at -20 °C under inert gas.

What Is the Organic Solvent Used with iTRAQ® Reagents during Shipment?

All iTRAQ®, aTRAQ™ and mTRAQ® reagents are shipped in acetonitrile from the factory.

What Are the Specifications of the Six-Protein Mixture Supplied with the iTRAQ® Kit?

Specifications of the six-protein mixture (PN 4348363) supplied with the iTRAQ® kit include the accession numbers of the proteins and their mass per tube (in µg and nmol).

iTRAQ® Reagents: Can Samples Labeled with Both the 4-Plex and 8-Plex Kits Be Mixed?

The iTRAQ® Reagents chemistry for 4plex versus 8plex kits is described.SCIEX does not recommend mixing samples labeled with the reagents from the two separate iTRAQ® kits, 4plex and 8plex, due to the differences in the reagent chemistry.

Protocols for Protein Precipitation in Samples before Using iTRAQ® Kits

To prepare samples prior to iTRAQ® reagent labeling, use the following protocols.

How Many Vials of Each iTRAQ® Reagent Are in the Multiplex Kit?

Each iTRAQ reagent multiplex kit (PN 4352135) contains 5 vials of of the following iTRAQ reagent labels: 114, 115, 116, and 117.

Tips and Tricks for Cation-Exchange Chromatography for the iTRAQ® Protocol

The manual injection procedure for the iTRAQ® protocol requires a 22-gauge syringe with a 2-inch needle (purchased separately). This article lists some tips and tricks on how to set up the syringe when using cation-exchange columns for samples treated with the iTRAQ reagent.

How do I store iTRAQ® labeled peptides?

Store iTRAQ® reagent labeled peptides at -20 or -80 degrees Celsius. Avoid having the peptides undergo multiple freeze/thaw cycles. iTRAQ-labeled peptides can degrade over time.

How do I modify the parameter translation file for mass tolerance and threshold for reporting iTRAQ ratios

Mass tolerance and threshold values for reporting iTRAQ ratios can be tuned by editing a configuration file.

Can ethanol be substituted for isopropanol when performing iTRAQ protocol for 4Plex and 8Plex

Can ethanol be substituted for isopropanol when performing iTRAQ protocol for 4Plex and 8Plex