新式成象技术可提供更清晰的分子图

With intensity a million times brighter than sunlight, a new synchrotron（同步加速器） -based imaging technique offers high-resolution pictures of the molecular composition of tissues with unprecedented speed and quality. Carol Hirschmugl, a physicist at the University of Wisconsin-Milwaukee (UWM), led a team of researchers from UWM, the University of Illinois at Urbana-Champaign and University of Illinois at Chicago (UIC) to demonstrate these new capabilities. Hirschmugl and UWM scientist Michael Nasse have built a facility called "Infrared Environmental Imaging (IRENI)," to perform the technique at the Synchrotron Radiation Center (SRC) at UW-Madison. The new technique employs multiple beams of synchrotron light to illuminate a state-of-the-art camera, instead of just one beam.

IRENI cuts the amount of time needed to image a sample from hours to minutes, while quadrupling（四倍） the range of the sample size and producing high-resolution images of samples that do not have to be tagged or stained as they would for imaging with an optical microscope.

"Since IRENI reveals the molecular composition of a tissue sample, you can choose to look at the distribution of functional groups, such as proteins, carbohydrates（糖类） and lipids," says Hirschmugl, "so you concurrently get detailed structure and chemistry."

The technique could have broad applications not only in medicine, but also in pharmaceutical drug analysis, art conservation, forensics, biofuel production, and advanced materials, such as graphene（石墨烯） , she says.

Funded by $1 million grant from the National Science Foundation's Major Research Instrumentation Program, the development of the facility has quickly attracted other projects supported by the NSF and the National Institutes of Health. It is published online today in Nature Methods.

The work is a collaboration with the labs of Rohit Bhargava, assistant professor of bioengineering at the University of Illinois at Urbana-Champaign and pathologists Dr. Virgilia Macias and Dr. André Kajdacsy-Balla at UIC. "It has taken three years to establish IRENI as a national user facility located at the SRC," says Nasse. "It is the only facility of its kind worldwide."