Antibodies may bind analytes and transduce a signal to a recognition element such as an electrode, film or waveguide(biosensing). However, standard attachment to biosensor surfaces results in random antibody orientation. Often, only a small proportion of surface-bound antibodies are oriented in a manner amenable to binding the antigen. A potential solution is to use an adapter protein such as protein A or protein G. These proteins bind to the Fc region of antibodies which frees their antigen-binding domains. A better biosensor may incorporate a protein A or G coated surface which can then bind and properly orient antibodies. The corresponding increase in the density of antigen binding sites may increase the sensitivity of a biosensor. Protein Mods offers protein A and recombinant protein G that have been modified to contain thiols. These thiolated proteins can form gold-thiol bonds, a convenient attachment chemistry for use in surface plasmon resonance applications, generating colloidal gold conjugates or functionalizing gold electrodes. For a negative control, unmodified protein A and G (which contain no thiols) are also available.
- Thiolated protein G: 1 millgram for $122, 5 mg for $323.
- Unthiolated (control) protein G: 1 millgram for $48, 5 mg for $142.
- Thiolated protein A: 2 mg for $82, 10 mg for $224
- Unthiolated (control) protein A: 2 mg for $39, 10 mg for $64
For more information contact operations@proteinmods.com.
