FAQs

How long should I expect to wait for the lab results after the beginning of the analysis?

Protein Identification and Label free quantitation, 2 weeks;

Protein Quantification using iTRAQ and TMT, 6 weeks.

What quantity of proteins is needed for the analysis?

If you submit the SDS-PAGE gel bands, we need a visible band either with Coomassie blue staining or SyproRuby staining.

For PTM identification, we need a strong coomassie blue stained gel band.

For protein mixture, we need the protein amount no less than 10 µg.

For protein quantitation using iTRAQ and TMT labeling, we need 100 µg from each sample.

For global PTM quantitation, we need no less than 0.5mg from each sample.

How should the samples be prepared?

For the sample separated by SDS-PAGE, you may either submit the whole SDS-PAGE, or excised gel bands in Eppendorf tubes with a drop of ddH₂O. If you are sending the whole SDS-PAGE, please wrap the gel with Saran Wrap and ship it to us in room temperature. Please use either Coomassie blue, or SYPRO Ruby to stain the gel.

For solution samples, please provide the buffer composition and protein concentration prior to sample submission. Please send the samples with dry ice.

For tissue samples, please remove the blood before frozen. Please send the samples with dry ice.

For cell pellet samples, please wash the cells with 1X PBS before collecting the cells. Please send the sample with dry ice.

Why do I see keratin in my samples?

Keratins are everywhere; human skin flakes and human hair are the most probable reason for predominant keratin results. Make sure that you keep samples uncontaminated by using powder-free gloves, keeping samples shielded from outside contaminants, refraining from touching the sample with bare hands, and avoiding community reagents. Also, clean lab glassware or plastic wares with bleach prior to using them. Try to use dedicated lab wares for protein chemistry. Do not use recycled reagents, dyes, etc.

Why do I see albumin and casein in my gel-purified samples?

If the sample came from a cell culture or your sample was a tissue sample that still had blood on it, your sample will have albumin contamination. If the sample was housed in a container that was previously used for western blotting, it may contain casein, an abundant milk protein.

What kind of protein post-translation modifications have you been able to detect?

Phosphorylation, Nitrosylation, Methylation, Acetylation, Disulfide bond, Ubiquitylation, Carboxylation, Sulfonation, Citrullination, etc.

Why do you need a larger quantity of proteins for phosphorylation site mapping than for identification?

For phosphorylation site mapping, less than 5% of proteins are phosphorylated, so certain phosphor-enrichment steps are required before phosphorylation site mapping can occur.

What is the shipping address?

90 Bergen Street, Newark NJ 07103.