| TECHNOLOGY |
Venus flytraps for proteins A new type of nanotube-based biosensor acts as a sort of Venus flytrap for detecting proteins. It consists of cone-shaped gold nanotubes embedded in a polymer membrane derivatized with a protein-specific molecular recognition agent. An ion current runs through each nanotube. When analyte protein is present, it binds to the specific agent and gets stuck in the conical channel, blocking the ion current. The change in current is what is sensed. The reagentless biosensors have up to 100-femtomolar sensitivity. Charles R. Martin of the University of Florida and his coworkers developed them and demonstrated their use on three proteins, including the bioterror agent ricin (J. Am. Chem. Soc. 2005, 127, 5000). "They have potential medical and defense applications," comments Hagan Bayley of the University of Oxford, England. The new biosensors are currently single-use because the analyte-binding process is irreversible. "Nanopore sensors of this type for continuous sensing would also be desirable," Bayley notes. |
|
Want more information ? Interested in the hidden information ? Click here and do your request. |