Liquid chromatography coupled to mass spectrometry (LC MS/MS) has become the backbone for understanding biochemical pathways to discovering new biomarkers for debilitating diseases. ITSI Biosciences has been utilizing advanced LC-MS/MS technologies to provide unsurpassed protein identification and characterization services for more than 6 years. The services are offered to both industrial and university clients at a competitive price and faster turnaround time.

We utilize state of the art techniques and constantly update our skills and equipment to accommodate the constantly evolving proteomics field.  Some of the areas of proteomics which we specialize in are listed below. This list is just for reference and is not exhaustive. Please don't hesitate to call us for techniques not listed here.

In-gel Digestion:
Gel Electrophoresis provides the reproducible, affordable and reliable way to fractionate proteins based on molecular weight or in combination with pI to reduce sample complexity at the protein level. Our in-gel digestion workflow includes spot picking, digestion and mass spec analysis from 1D and 2D gels.
Apart from the analytical services, we offer an innovative kit (ProDM – Cat #: K-0021-10) to check for completion of trypsin digestion without gel electrophoresis prior to mass spectrometry. This is valuable for clients mailing precious samples that don’t have the means or time to verify complete trypsin digestion. 

We also offer image analysis and spot detection, automated spot picking and digestion from 2D-DIGE gels. We work with a variety of gel stains including Sypro Ruby, Coomassie blue, and fluorophores.

In solution / GelFree  Digest
Un-fractionated or fractionated samples such as those from online protein fractionation can be directly digested using trypsin or other proteases including aspN, Glu-C, and ArgC. This approach eliminates time consuming SDS-PAGE and also reduces the loss associated with protein recovery during in-gel digestion. We have expertise to optimize nano-LCMS for working with tryptic peptides and also with non-tryptic peptides including naturally occurring peptides - e.g. from cerebrospinal fluid.

Phosphopeptide identification
Identifying proteins is the first step and identifying post translational modifications including phosphorylation is prerequisite to assigning a role to the protein in a signaling pathway or in other biochemical pathways. We have extensive experience in method development for enriching phosphopeptide using either TiO2 or IMAC approach. Apart from TiO2 or IMAC approaches, we also have expertise for using SCX fractionation for phosphopeptide fractionation / enrichment.

Biomarker Analysis:
Plasma / Serum Depletion:
We have both in-house validated albumin depletion kit (ASKc; Cat #K-0012-10 and
ASKs; Cat #K-0013-50) and a 14 proteins depletion kit for depletion of abundant proteins from serum/plasma prior to analysis. Removing 14 most abundant proteins reduces plasma protein concentration by 90 %. Without depletion it is impossible to identify biomarkers which are usually in the low copy numbers compared to albumin or IgGs. Depleting them increases our ability to identify low abundant proteins and hence candidate biomarkers. 

Quantification:
As part of the biomarker analysis workflow process we offer protein quantification using iTRAQ labeling.  We are successfully employing 4 or 8-plex iTRAQ for identifying proteins that show differential expression in biopsies, urine, serum, plasma and other body fluids.