"Antibodies aren't [only] a critical part of the body's defense against disease: they're also the gold standard for biosensing. These natural proteins are widely used in diagnostic tests for cancer and other diseases because they recognize and bind so efficiently to disease markers, which include bacterial and viral proteins and protein fragments. However, protein antibodies are expensive to synthesize in the lab and only last a few months. Now biochemists have developed a method to make artificial antibodies that may be just as effective as the real thing."
Molecular imprinting is a technique where polymerization occurs in the presence of the target molecule. The polymer takes on the shape of the target, which is subsequently removed. In much the same way as the 'lock and key' binding of antibodies with antigens, the polymer will subsequently bind to the target molecule that fits the nano-structured shape molded into the polymer.
Researchers Takashi Kodama and Yoshio Okahata (Tokyo Institute of Technology, Yokohama), Yu Hoshino and Kenneth J. Shea (University of California, Irvine) have developed a novel way to improve the efficiency of the imprinted polymer and the range of target molecules that can be bound by using combinations of various monomers in the molecular imprinting process and then screening the final polymer nanoparticles for effectiveness and selectivity.
The polymerization and selection process occurs at ambient temperatures and uses water as a solvent. The result is inert and stable. The work was done using the target molecule melittin - additional research is underway to extend the range of target molecules and explore specific applications.
The paper Peptide Imprinted Polymer Nanoparticles: A Plastic Antibody was published in the Journal of the American Chemical Society (subscription required).