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

Abstract

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 nonoxidized 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 tumorbearing 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.while O-GaIn displayed an uneven cut surface with air holes inside (Figure 1b-II,-III). In addition, SEM images revealed that GaIn had a glossy surface, while an obvious rough oxide layer appeared on the surface of O-GaIn-30 and many metal oxide particles arose on the surface of O-GaIn-60 (insets of Figure 1c-e). These SEM images illustrated that different stirring time

Galvanic replacement reaction for in situ fabrication of litchi-shaped heterogeneous liquid metal-Au nano-composite for radio-photothermal cancer therapy

“…Rapid progress on the biomedical application of liquid metals (LM) has witnessed the tremendous research advance of these novel functional materials [ [1] , [2] , [3] , [4] , [5] ]. Simultaneously owning multi-properties such as high fluidity, excellent thermal and electrical conductivities, ideal biocompatibility, good radiopacity, controllable behaviors and conformability associated with reversible liquid-solid phase transition, facile manufacture and along with affordable cost, LM biomaterials have been widely applied in biological imaging [ 6 , 7 ], bone repair [ 8 ], drug delivery [ [9] , [10] , [11] ], magnetic hyperthermia [ 12 , 13 ], photothermal therapy [ [14] , [15] , [16] ], tumor embolotherapy [ 17 ], microwave dynamic therapy and microwave thermal therapy [ 18 ]. Such ‘One material, Multi-functionalities’ is rather unusual among many existing top materials and therefore it is noteworthy to recognize that a new direction of biomedical category: the LM biomaterials have formed [ 2 ].…”

Conformable on-skin devices for thermo-electro-tactile stimulation: materials, design, and fabrication

“…Conversely, Wang et al modified the adhesion properties of EGaIn by thorough oxidation. 91 After stirring in air, the adhesion between the LM and the skin increase drastically and the authors were able to write circuits directly on skin using a brush. They also demonstrated that these structures could be used for wireless thermotherapy by inducing a current with an alternated magnetic field.…”

Interfacial Engineering of Room Temperature Liquid Metals

“…Figure 2A presented that the introduction of oxygen by agitation increases the content of gallium oxides and reduces the fluidity of gallium-based metals (Ga x In 1− x ). [1,49] The XPS images of eutectic GaInSn alloy (EGaInSn) revealed that the mixed oxides (Ga 2 O 3 ) were on the surface and elements In and Sn exhibited inner. [50] Since the natural environment contains enough oxygen, the mechanical strength of liquid metal droplets can be adjusted by controlling the degree of oxidation of the liquid metal.…”

“…Figure A presented that the introduction of oxygen by agitation increases the content of gallium oxides and reduces the fluidity of gallium‐based metals (Ga x In 1− x ). [ 1,49 ] The XPS images of eutectic GaInSn alloy (EGaInSn) revealed that the mixed oxides (Ga 2 O 3 ) were on the surface and elements In and Sn exhibited inner. [ 50 ]…”