Abstract
The combination of Ca(2+) overload and reactive oxygen species (ROS) production for cancer therapy offers a superior solution to the lack of specificity in traditional antitumor strategies. However, current therapeutic platforms for this strategy are primarily based on non-targeting nanomaterials, leading to undesirable off-target side effects. Additionally, resistance to ROS and apoptosis induced by the hypoxic tumor microenvironment (TME) further limits therapeutic efficiency. Herein, a magnetic microrobot based on living Spirulina Platensis (SP), which is coated with a double layer of Fe(3)O(4) nanoparticles (NPs) and CaCO(3) NPs. The microrobots can accumulate in tumor regions under magnetic attraction, which produces a high-Ca(2+) environment under the acidic TME and facilitates Ca(2+) overload under ultrasound (US) stimulation. Meanwhile, sufficient oxygen (O(2)) production by photosynthesis helps alleviate hypoxia and promotes in situ ROS production by chlorophyll-mediated photodynamic therapy (PDT), which can coordinate with Ca(2+) overload to induce cell apoptosis. With these unique properties, the SP-based microrobots offer a promising microrobotics-based strategy for in situ Ca(2+) accumulation and ROS production, contributing to a precise and effective way for cancer treatment.