Fig. 2. Cell trapping and stretching.

a Schematic diagram of laser propagation in optical stretching and the distribution of the gradient force along the center of the channel. b Two-beam laser traps one MCF7 cell from the side into the center of the main microchannel under the collective action of gradient and axial forces. c Cell being trapped at a lower power (100 mW per fiber). d Cell stretching at a higher power (400 mW per fiber)