Optical tweezers use laser light to manipulate small particles. A new method has been advanced using Stampede2 supercomputer simulations that makes optical tweezers safer to use for potential biological applications, such as cancer therapy. (a) Image shows schematic of red blood cells in solution. (b) Timelapse showing trapping and thermal rupture at ambient temperature. (c) Timelapse of trapping using new method. No cell rupture is observed.