- Price: please
see Price list.
- Turnover Time:
usually five business days.
- Quality Guarantee:
We guarantee a successful identification for any eligible sample
or it will be free of charge. However, there are certain cases in
which a sample is not eligible for the guarantee due to reasons
not related to the quality of our service:
a). Samples from a un-sequenced species.
Since LC-MS/MS based protein identification depends on protein
sequence database, lack of it may make it difficult or even
impossible to identify correct proteins. In many cases, we may
identify the correct proteins from other closely related species
that have been sequenced. Such a "cross-species"
identification strategy often works well with samples isolated
from mammalian, but the success rate is much lower for samples
isolated from un-sequenced species of bacteria, fungi, plants, or
insects.
b). Silver stained gel bands. We can't guarantee the success in
identification proteins from a silver stained samples due to two
reasons: i) some types of silver staining procedures lead to the
cross-link of proteins to gel matrix, making it impossible to
extract peptides out of gel. ii). the level of protein in a silver
stained sample may be below the minimal amount required for
protein identification. For example, the so-called MS compatible
silver-staining kit from Invitrogen (SilverQuest, LC6070) claims a
detection limit of 0.3 ng of protein, or 3 femtomole for a 100 KD
protein. At such a low level, the loss of peptides during in-gel
digestion due to adsorption to tubes, pipette tips or a syringe
may become so severe that there is practically nothing left for MS
analysis. However, in reality, most samples contain more than 2 ng
of protein, and our success rate in analyzing silver stained
samples is about 85%-90%.
- Customer Support:
We provide a free, email-based technical support for any technical
questions with a 24-hour response time. We can provide free
assistance for customers to present and to publish their results,
including text drafts of the experimental methods related to our
analysis, and one raw MS/MS figure for each sample. We can also
make publication-quality MS/MS figures at some moderate cost. We
don't request any co-authorship in the related publications. For
additional support, please contact
us.
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