Single Polymers Jiggle Predictably

Michael D. Wheeler

PASADENA, Calif. -- DNA molecules submerged in water vibrate harmoniously, according to a recent study enabled by photonics and reported in the July 10 issue of Nature.
Physicist Steven Chu of the California Institute of Technology and a student immersed dyed strands of DNA in water and used a laser tool called optical tweezers to study the vibration of polymers in plastics, synthetic fabrics and the DNA in living cells. The pair discovered that the immersed strands adhered closely to the 200-year-old physics law.
Scientists previously studied polymer motion only in bulk and believed they would exhibit more complex behavior.