Stretchable and Skin-Attachable Electronic Device for Remotely Controlled Wearable Cancer Therapy

Abstract

Surgery represents a primary clinical treatment of solid tumors. The high risk of local relapse typically requires frequent hospital visits for postoperative adjuvant therapy. Here, device designs and system integration of a stretchable electronic device for wearable cancer treatment are presented. The soft electronic patch harnesses compliant materials to achieve conformal and stable attachment to the surgical wound. A composite nanotextile dressing is laminated to the electronic patch to allow the on-demand release of anticancer drugs under electro-thermal actuation. An additional flexible circuit and a compact battery complete an untethered wearable system to execute remote therapeutic commands from a smartphone. The successful implementation of combined chemothermotherapy to inhibit tumor recurrence demonstrates the promising potential of stretchable electronics for advanced wearable therapies without interfering with daily activities.

Keywords: cancer therapy; liquid metal conductor; stretchable electronics; wearable heater; wearable therapy.

Figure 1

Intrinsically stretchable electronic patch for wearable cancer therapy. A) Schematic illustration of the conformal attachment of the stretchable electronic patch to the postoperative surgical wound for on‐demand delivery of therapeutic drugs and thermal actuation under remote commands from a smartphone. B) As‐prepared electronic patch under different mechanical manipulations, including bending (left), twisting (middle), and stretching (right).

Figure 2

Compliant composite nanotextile dressing. A) Schematic illustration of the co‐assembly process to create composite nanofiber textile. B) SEM images of the composite nanotextile at the pristine state (top) and after thermal treatment (bottom). C) Optical images of the RhB‐loaded composite nanotextile at different tensile strains. D) Uniaxial stress‐strain curves of the composite nanotextile at the pristine state and after thermal treatment. E) Differential scanning calorimetry (DSC) curves showing the stable phase transitions of trapped microcarriers at multiple scans. F) DOX release profile of the composite nanotextile at different temperatures. G) Release profile in response to thermal actuation cycles. H) Cumulative release of DOX from composite nanotextiles within ≈4 h at 37 and 55 °C under different tensile strains. I) Cell viability of B16F10 cells exposed to the pristine culture medium (control), free DOX (0.5 µg mL⁻¹), TPU nanotextile at 55 °C for 5 min (Tex. TT), and composite nanotextile at 55 °C for 5 min (DOX‐Tex. TT). Data are presented as mean ± SD of n = 6. Statistical differences are determined by two‐tailed Student's t tests (*p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001).

Figure 3

Compliant electroresistive heater. A) Normalized resistance versus tensile strain of liquid metal conductors. B) Liquid metal‐based serpentine mesh heater at different tensile strains. C) Temperature profiles at different applied voltages. D) Infrared camera images of the heater at different voltages. E) Temperature responses to 120 on/off voltage cycles with an amplitude of 1.5 V. F) Temperature as a function of the tensile strain under a drive voltage of 1.5 V.

Figure 4

Integrated self‐powered wearable electronic system. A) Schematic showing the layer‐by‐layer construction of the stretchable electronic patch. B) Optical images of the patch at different strains. C) Optical image of a fully integrated electronic system (top) and block diagram of the operation principles (bottom). D) Temperature of the electronic patch versus electrical power under different driving modes. E) Infrared camera images of the electronic patch at 0% (top), 30% (middle), and 50% (bottom) strains. The dashed line indicates the area of composite nanotextile loaded with anticancer drugs. F) Optical image (top) and corresponding infrared camera image (bottom) of a fully integrated electronic system operated on a freely moving mouse. G) Optical images (top) and corresponding infrared camera images (bottom) showing the stable operation of the integrated system attached to the forearm under hand motions.

Figure 5

In vivo efficacy of wearable cancer therapy. A) Tumor growth curve of postoperative tumor models receiving no treatment (control), free DOX, wearable electro‐thermal therapy (ETT), and wearable combined therapy. B) Optical images of harvested tumors after the treatments. C) Histopathological analysis of tumor tissue sections based on H&E, TUNEL, and Caspase‐3 staining. Data are presented as mean ± SD of n = 4. Statistical differences are determined by one‐way ANOVA (*p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001).