Cells' Secrets Revealed
A Georgia Tech research team is using a modified atomic force microscope (AFM) to study the role of adenosine triphosphate (ATP) in cystic fibrosis (CF). Although a link has been discovered between elevated levels of ATP, a chemical associated with energy transport, and CF, quantitative measurements at the cell surface that might help explain the trigger mechanism have proved elusive.
Stephanie vL Henkel
Modifications to the AFM consisted of adding recessed micro-and nanoelectrodes to the tip, in effect combining an AFM with a scanning electrochemical microscope to take advantage of the capabilities of both. This "universal tool" can simultaneously monitor both topography and electrochemical activity at the cellular level.
According to researcher Boris Mizaikoff, many pathological events disrupt chemical communication and molecular signaling among cells, and knowing more about the way cells communicate will be helpful in new treatments for disease. "Being able to operate sensors in an electrochemical imaging mode at the micro-and nanoscale is an exciting opportunity for complementing optical imaging techniques. There are many clinical research problems that these biosensors can help with," Mizaikoff notes.
For the ATP study, sponsored by the National Institutes of Health and carried out in collaboration with Douglas Eaton at Emory University's School of Physiology, the Georgia Tech investigators used the modified AFM to study ATP release at the surface of live epithelial cells, those that cover most glands and organs in the body.
In addition to Mizaikoff and Eaton, the researchers consisted of team leader Christine Kranz, Jean-Francois Masson (photo), and Justyna Wiedemair.
(For the full report, go to www.sensorsmag.com/0706/RDCell)
Bullets vs. Soft Body Armor
"Frangible" bullets are designed to break into small bits when they strike a hard surface. This ammunition might appear counter-intuitive, but it is used by law enforcement personnel in areas where ricochets could harm innocent bystanders. Now the question has arisen as to how frangible bullets might behave should they strike the soft body armor worn by police and first responders. NIST researchers are using a Kolsky bar apparatus to find out. (www.sensorsmag.com/0706/RDBullet)
3D Facial Scans in 40 ms
Computer scientists at Sheffield Hallam University, U.K., have developed a new face recognition software that can produce an exact 3D image of a face within 40 ms. A pattern of light is projected on a face, creating a 2D image, from which an accurate 3D representation is generated. In addition to security applications, the technology could be used to detect defects in products passing by on a conveyor belt. (www.sensorsmag.com/0706/RDScan)
Census Taking Made Easier
AuthenTec's fingerprint sensors will facilitate the 2010 U.S. census by eliminating much of the verifying paperwork the head counters have had to provide in the past. The company's EntrePad 1510 sensor will be embedded in more than 500,000 PDAs that census takers will use to directly capture information collected during interviews. The head counters will enroll their fingerprints and then slide their fingers across the sensor to authenticate that the information was input by them. This is part of a program to integrate various automated systems to obtain field census data. (www.sensorsmag.com/0706/RDCensus)
Blood Plasma Reveals Cancer
Quest Diagnostics Inc. has launched the first of its Leumeta cancer testing assays, designed as an alternative to bone marrow biopsies (which everyone would prefer to avoid). The assays identify and analyze genetic components of leukemia and lymphoma tumors using blood plasma instead of bone marrow, and can measure the amount of cancer in a patient, detect certain blood cancer markers, and assist the physician in monitoring the efficacy of the treatment being administered.(www.sensorsmag.com/0706/RDPlasma)