Printed Conformable Liquid Metal e-Skin-Enabled Spatiotemporally Controlled Bioelectromagnetics for Wireless Multisite Tumor Therapy

With inherent flexibility, high electroconductivity, excellent thermal conductivity, easy printability and biosafety, gallium-based functional liquid metals (LMs) have been increasingly evaluated for biomedical applications, especially as electronic skin (e-skin). Extending these versatile materials to more challenging applications is a worthwhile pursuit. To realize precise and spatiotemporal multisite tumor treatment under an alternating magnetic field (AMF), an oxidized GaIn (O-GaIn) mixture-based e-skin is developed and demonstrated to be printable. Compared with the commonly utilized non-oxidized GaIn, O-GaIn possesses outstanding adhesion to the skin surface and can be directly and quickly printed into various customized patterns. The LM e-skin thus constructed as conformable bioelectrodes on tumor-bearing mice exhibits evident feasibility for administrating non-invasive wireless multisite tumor therapy under AMF exposure due to its favorable magnetothermal effects. These in vivo experiments reveal remarkable tumor growth inhibition and increased life span in mice, especially in the case of multilesion treatment. A favorable biomedical strategy based on O-GaIn material for developing future non-invasive and high-performance cancer therapy, which is also promising for treating whole-body diseases in the future, is provided.