Protein Identification-ProtTech Inc.

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Terms: Turnover Time/Guarantee/Support

1、Turnover Time: usually five business days.

2、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%.


3、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.