A Self‐Reporting Mineralized Conductive Hydrogel Sensor with Cancer‐Selective Viscosity, Adhesiveness, and Stretchability

Abstract

A cancer‐selective self‐reporting sensor based on a redox‐responsive mineralized conductive hydrogel (M‐Hydrogel) is proposed with cancer‐specific viscosity, adhesive strength, stretchability, tunable conductivity, and fluorescence. The redox‐triggered release of carbonized polydopamine (cPDA) from the loaded disulfide‐crosslinked polymer dots (PD@cPDA) in the hydrogel matrix modulates the macroporous structure responsible for self‐recognizable cancer sensing and photothermal activity for cancer therapy. The self‐reporting nature of the M‐Hydrogel sensor is highlighted when in vicinity of a high glutathione (GSH) level owing to the controllable pore size and H‐bonding by cPDA, as confirmed by experiments on cancer cells (HeLa, PC3, B16‐F10‐GFP, and SNU‐C2A) and normal cells (CHO‐K1). The lower viscosity during syringe test along with the exceptional adhesiveness and stretchability with various cancer cells, combined with a high wireless pressure‐sensing response absent in normal conditions, confirms the dependence of self‐recognizable behavior on the cancer microenvironment. The M‐Hydrogel demonstrates excellent ex situ sensing with tumor ablation, after implantation in mice xenografted with HeLa cells, with the wireless sensing system, enabling real‐time analysis coupled with the upregulation of pro‐apoptotic markers P53 and BAX in the tumor. Therefore, this self‐reporting sensor may facilitate a strategy for innovative and convenient cancer diagnostics.

Preparation and Characterization of Chitosan/Hydroxypropyl Methylcellulose Temperature-Sensitive Hydrogel Containing Inorganic Salts for Forest Fire Suppression

“…Viscosity is an important index to respond to the fluidity and permeability of hydrogels, which affects the application performance of gels [ 42 , 43 ]. Since hydrogels are subjected to shear in mixing, extrusion, or pumping, it is necessary to explore the relationship between sol viscosity and shear rate using a rotational rheometer [ 44 ], and the test results are shown in Figure 3 C. From Figure 3 C, a consistent decrease in viscosity across all samples with increasing shear rate at room temperature was observed—a phenomenon known as shear thinning.…”

“…Viscosity is an important index to respond to the fluidity and permeability of hydrogels, which affects the application performance of gels [42,43]. Since hydrogels are subjected to shear in mixing, extrusion, or pumping, it is necessary to explore the relationship between sol viscosity and shear rate using a rotational rheometer [44], and the test results As can be seen in Figure 3A, the process from 40 • C to 145 • C was dominated by the continuous evaporation of the free water with a weight loss of 84%, which helped to reduce the temperature and dilute the oxygen, and thus mitigating combustion.…”

Progress of Research on Conductive Hydrogels in Flexible Wearable Sensors

“…Their self-repairing ability [87][88][89] is a crucial characteristic which ensures that sensors can still stably transmit electrical signals after experiencing mechanical damage, thereby extending the sensor's lifespan and reducing electronic waste. Additionally, hydrogel sensors should possess adhesiveness [90,91], and establish a stable and reliable contact interface with human tissues to capture small physiological signals without the use of adhesive tape. More importantly, hydrogel sensors using water as a dispersion medium can experience water evaporation and low-temperature freezing hardening, severely affecting the sensor's long-term stability.…”

Hydrogels for Chemical Sensing and Biosensing

“…The changes of color are often directly related to the concentration of the analyte. [28][29][30] A hydrogel superimposed with a glass fiber membrane and ribbon colorization was used to detect nitrite ions. The hydrogel superimposed on glass fibers is covalently immobilized with N-(1-naphthyl) (1-Nap), one of the Griess reagents used for the colorimetric reaction of nitrite.…”