Optical Tweezers
Special techniques were developed in order to manipulate and move objects at the nano-scale. Optical tweezers make use of a highly focused laser beam to exert a force on dielectric particles. The focused beam contains a relatively strong electric field gradient that is able generate a force on a microscopic object, usually at the pico-Newton level. By pushing and pulling at the microscopic level, we are able to measure how physical forces interact with biological systems. The video below shows how optical tweezers can break apart a red blood cell.
[Youtube video link] https://www.youtube.com/watch?v=QkZ95RF_Zf4