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This is Scientific American's 60-Second Science, I am Cynthia Graber. This'll just take a minute.

Imagine tweezers¹ so fine that you could reach right into a cell and manipulate individual molecules². MIT researchers have created such a tweezer, using beams of light. The tweezer is so precise it’s been used to determine how strong the chemical bonds are between two protein molecules in a cell. The research was published in the June 30th edition of the Proceedings³ of the National Academy of Sciences. It builds on work published last fall, when the same scientists demonstrated that so-called optical tweezers could pick up and move cells on a microchip. Scientists wanted to investigate protein bonds to get a better understanding of the forces that give cells structure and the ability to move around. They used the light-beam tweezer to pin one type of protein in place. Another beam tugged⁴ at a second protein, which eventually broke completely away from the first. By knowing the energy necessary to break the bond, the scientists were in fact measuring the strength of that bond. Researchers say the tweezers can be applied⁵ to hundreds of other protein interactions that make up the cell’s architectural skeleton, potentially teasing out secrets of how cells work.

Thanks for the minute for Scientific American's 60-Second Science, I'm Cynthia Graber.