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

Actively Triggerable Metals via Liquid Metal Embrittlement for Biomedical Applications

“…Moving forward, future toxicity studies specific to different form factors and dosages are recommended to inform the continued development of actively triggerable metal‐based biomedical technologies that utilize liquid metal stimuli. Overall, the promising biosafety of orally administered EGaIn at a high dose, coupled with previous literature that has also identified specific biocompatible forms and routes of administration for EGaIn, [ 15,17,21,36,37 ] suggest that EGaIn can be safe to use within the body for biomedical purposes.…”

Magnetic and injectable Fe-doped liquid metals for controlled movement and photothermal/electromagnetic therapy

“…The slope experiment was designed, in which LM, 5%Fe/LM, and 10%Fe/LM were put on pig skin with one end raised to different angles. 18 As shown in Fig. 1C, the LM droplet slipped down at an inclination angle of 301.…”

“…The stirring time should not be too long to avoid the oxidation of LM. 18 The uniformity of 5%Fe/LM could be ensured by increasing the stirring speed. As shown in Fig.…”

Soft Artificial Muscle of Poly(vinyl chloride) Gel with an Imperceptible Liquid Metal Electrode

“…After mechanical oxidization, the OLM formed behaves like a paste with a rough surface and silver- white color (Figure S3b), which exhibits a stronger adhesion ability to substrates than the original LM due to the existence of Ga 2 O 3 . 32 A previous study has demonstrated that the increasing Ga 2 O 3 content in OLM would cause the decreasing surface energy, 39 and the decrease in surface energy enables OLM to adhere better to various substrates, which helps in patterning of LM and maintains the structure of the LM pattern. 31,40 Here, the critical factor of the surface energy of OLM was measured and calculated by eqs S1 and S2 according to Fowkes' work, 41 as shown in Note S1, Table S1, and Table S2.…”