Chemistry and Biochemistry

Finding Proteins With Laser Vision

Posted: Apr 15, 2011

Finding and studying important proteins has become more efficient and more accurate using newly developed laser technology in the Department of Chemistry and Biochemistry at Brigham Young University.

Because proteins are involved in almost every function within the human body, scientists are extremely interested in understanding how they work. During the last two years Dr. Paul Farnsworth and graduate student Matt Heywood have been fine-tuning a new method for detecting and studying proteins.

“Sometimes there’s an interest in finding a particular protein that may be a disease marker or something like that,” Farnsworth said. “We wanted a general purpose detector that could detect very small quantities of [these kinds of] proteins.”

To study proteins scientists shine a laser on them as they flow through a thin tube, causing them to fluoresce. In order to make them more visible, protein molecules have typically been altered through a chemical reaction that adds fluorescent tags. While the added fluorescence is helpful in studying the proteins, it creates changes in the molecular structure that can confuse the results.

Farnsworth’s method employs an ultraviolet laser that causes the proteins to fluoresce without having to chemically mark them first. Using this method, scientists could potentially detect and identify proteins without changing their structure or function. One of the difficulties with this new technique is even though the proteins do fluoresce on their own, they will lose their fluorescent properties if they are exposed to too much ultraviolet light.

“You’re kind of caught between a rock and a hard place,” Farnsworth said. “In order to get the best results, you have to be careful about how much light you expose the proteins to and for how long, and then [figure out] how best to detect the light that comes out.”

To find the ideal settings for detecting the proteins, Farnsworth developed a mathematical model that predicts how much light the proteins are exposed to as they flow through the thin tubes. He and Heywood then spent the rest of their time verifying the results of the mathematical model.

Using this new method, it may be possible in the future to detect proteins associated with certain diseases or medical conditions accurately, quickly, and inexpensively.

By Erik Westesen, College of Physical and Mathematical Sciences