Proteomics Services Sample Preparation Information





Protein Identification and Profiling Service


  1. Gel Band Sample:

Samples should be prepared by running the desired protein sample down a 1D SDS-PAGE gel or a 2-dimensional SDS-PAGE gel. Sample purity is critical in obtaining good protein identification. Therefore 2-Dimensional SDS-PAGE is the preferred method of sample preparation.

SDS-PAGE gels should be stained with stains compatible with MS analysis. It includes Coomassie Blue, SYPRO Ruby and silver stain. Only Silver stain compatible with mass spectrometry can be accepted.

For samples from Coomassie Blue and MS compatible Silver Stain, pooling of 2 spots is sufficient for 1 MS analysis. For weaker stains like SYPRO Ruby and Cy dyes, pooling of 4 spots is recommended. Proteins should be excised from the SDS-PAGE gel and placed in dried 1.5mL of microtubes.

  1. Solution / Liquid Sample:

Please ensure the information on sample concentration, volume, and type of buffer is indicated on the order form should you be submitting solution / liquid protein sample.

Points to note when submitting solution / liquid sample:

  1. Must provide sample that is pure and in a low salt buffer (e.g. 50mM ammonium hydrogen carbonate). For TRIS or phosphate buffers the maximum salt strength is 20mM. NaCl and surfactants (e.g. SDS) cannot be present.
  2. Recommended to submit 100ug, lyophilized. Kindly contact us if there are limitations to getting the required concentration.
  3. The sample must be freeze dried or lyophilised in a micro-centrifuge tube prior to shipping.





N-Terminal Protein Sequencing

Samples can be analyzed either from PVDF membranes; or in solution (sample preparation charges applies).

Kindly refer to our guidelines when submitting samples on a PVDF membrane.