Nano-actuators having a helical member formed with a ferromagnetic shape memory alloy (FSMA) are disclosed that are elastically deformable between a compressed state and an expanded state by the application of a magnetic field. The nano-actuators may include a ferromagnetic head portion, that may be formed from the FSMA or from another material. A thin biocompatible external layer provides a platform for attaching a ligand that is selected to bind with a target cell type, for example, a target cancer cell. The nano-actuators are magnetically propelled to the target cells, and oscillated and/or rotated to mechanically damage the target cells to induce apoptosis. The nano-actuators may be formed by electro deposition of the FSMA into a nano-helical template.