Proteomics Sample Preparation
General Principles
1. Biohazardous Materials: We do NOT accept samples containing any biohazardous materials. If your samples contain any biohazardous materials, please make sure to deactivate them completely using the appropriate procedure and declare them in the order form. In addition, we do NOT accept any samples containing Level 4 biohazardous materials even if they are deactivated. Please refer to this page for the rank of biohazardous materials.
2. Please feel free to submit samples in whichever buffer that you would normally use. The standard sample preparation is covered by the DIGE gel cost. Such samples should have protein concentration in the range of 5-20 mg/ml. Additional charge may apply on samples that require extensive amount of the extra work such as protein eluting, concentrating, buffer exchange or serum abundant protein depletion.
3. Sample Buffer: For effective IEF separation, proteins must be solubilized, fully denatured and reduced. Protein samples can be rapidly lysed in a 2D lysis buffer containing strong denaturing reagents and protease inhibitors (optional). Proper lysis buffer can vary greatly depending on the source of the samples, and should be determined empirically.
If you want to use the lysis buffer that are compatible with IEF, please make sure that lysis buffer is free of both primary amines and sulfhydryl groups, and follow these guidelines:
| Not Acceptable | Acceptable |
| Reducing agents (e.g., DTT, TBP) Buffers other than Tris Salt (e.g., NaCl) Ionic detergents (e.g,. SDS) Nucleic acids Polysaccharides Lipids Phenolic compounds Insoluble material Other small ionic molecules | Tris base (< 30 mM) Urea Water Non-ionic or zwitterionic detergents (e.g. CHAPS) |