Protein Identification & Analysis-ProtTech Inc.

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ID of Gel Samples


Nano LC-MS/MS is currently the most sensitive and reliable method in identifying proteins from a SDS-PAGE separated protein band or 2D gel separated protein spot. We accept samples with various type of staining, including coomassie, coloidal coomassie, silver, fluorescent dye, Zn/Cu2+, etc. There is no minimal requirement for the amount of protein in a sample.


1. Digestion

2. LC-MS/MS sequencing

3. Database search

4. Validation

5. Reporting

Sample Requirement

  • To increase sequence coverage, we encourage you to do reduction and alkylation of your protein samples before running the gel. Please click here for detailed protocol.

  • The height of each gel slice (vertical dimension) should be less than 2.5 mm. A gel slice higher than 2.5 mm will be trimmed automatically to 2.5 mm in our processing. Although we will make our best effort to leave the major protein band, we cannot guarantee the protein band left after the trimming is the band of your interest.

  • Each 1D gel sample should contain only one visible protein band.

  • For a sample with low amount, you may send us a duplicate sample in a separate tube as a backup. There is no extra charge.

  • Please send us a copy of a photograph of uncut gel with submitted protein bands (spots) clearly marked. Such a photograph may help us to decide the best procedure for analyzing these samples.

  • In the case that a silver staining are needed in order to visualize protein bands, one should use a MS-compatible silver staining protocol or kit (such as Invitrogen SilverQuest).

  • Each sample should be free of contamination. Direct contact with bare hands, dirty gel containers, or the surface of a light box should be avoided.

Guaranteed Success 

It will be free of any charge for a gel (coomassie-stained) sample if its ID fails. This guarantee is limited to visible gel band and the protein sequences are present in the current NR database.