3D multicellular tumor spheroids (MCTSs) have recently emerged as a landmark for cancer research due to their inherent traits that are physiologically relevant to primary tumor microenvironments. A facile approach–laser‐ablated micro U‐wells–has been widely adopted in the past decade. However, the differentiation of microwell uniformities and the construction of arrays have all remained elusive. Herein, an improved laser‐ablated microwell array technique is proposed that can not only achieve arrayed MCTSs with identical sizes but can also perform high‐throughput drug assessments in situ. Three critical laser ablation parameters, including frequency, duty cycle, and pulse number, are investigated to generate microwells flexibly with a range from 170 to 400 μm. The choice of microwells is optimally arranged into an array via precise control of horizontal spacing (d_x) and vertical spacing (d_y) amenable of cell‐loss‐free culture during cell seeding. Harvested T24, A549 and Huh‐7 MCTSs from the microwell array correspond to approximately 75 to 140 μm in diameter. Anticancer drug screening of cisplatin validated IC50 values in 2D and MCTS conditions are 3.5 versus 9.1 μM (T24), 11.8 versus 277.7 μM (A549) and 33.5 versus 52.8 μM (Huh‐7), and the permeability is measured to range from 0.042 to 0.58 μm min⁻¹.

The quest for autonomous, self-healing electronic skins in artificial soft robots has sparked considerable interest. However, restoring the primary structure and integrated skin sensors of these robots to their original state after damage presents significant challenges for achieving a swift and straightforward healing process. Herein, we introduce an enhanced polymer known as maltose polyborosiloxane (PM PBS), designed as an exceptional skin substrate. Engineered with unique properties, PM PBS demonstrates remarkable self-healing capabilities. Notably, it achieves a maximum strain at break exceeding 3000% and exhibits swift self-healing, fully recovering within a mere 10 s under ambient conditions and 3 min under both frozen (−20 °C) and underwater conditions. Additionally, our study highlights that the integrated PM PBS electronic adhesive can self-heal within 20 s underwater. Furthermore, we showcase the versatility of self-healing PM PBS when combined with Ecoflex (denoted as PME), successfully integrating it into piezoelectronic sensors and soft pneumatic grippers featuring in situ capacitive tactile sensing. This multifunctionality aligns with the development of composite materials possessing self-healing, stretchable, and deformable properties. Noteworthy is the rapid response to self-healing exhibited by our PME robotic grippers, enabling recovery from damage in less than 1 min. In summary, the impressive combination of stretchability, rapid self-healing, and multifunctionality inherent in PM PBS positions it as a promising candidate for a diverse range of applications in soft robots, wearable technology, and beyond.

We present a bioinspired self-formation microdevice to boost both tumor spheroid-based bioassays and in vitro modeling of blood vessels.

In recent decades, vapor sensors have gained substantial attention for their crucial roles in environmental monitoring and pharmaceutical applications. Herein, we introduce a chameleon-inspired colorimetric (CIC) sensor, detailing its design, fabrication, and versatile applications. The sensor seamlessly combines a PEDOT:PSS vapor sensor with a colorimetric display, using thermochromic liquid crystal (TLC). We further explore the electrical characteristics of the CIC sensor when doped with ethylene glycol (EG) and polyvinyl alcohol (PVA). Comparative analyses of resistance change rates for different weight ratios of EG and PVA provide insights into fine-tuning the sensor’s responsiveness to varying humidity levels. The CIC sensor’s proficiency in measuring ambient humidity is investigated under a voltage input as small as 2.6 V, capturing resistance change rates and colorimetric shifts at relative humidity (RH) levels ranging from 20% to 90%. Notably, the sensor exhibits distinct resistance sensitivities of 9.7 mΩ (0.02% ∆R/R₀)/%RH, 0.5 Ω (0.86% ∆R/R₀)/%RH, and 5.7 Ω (9.68% ∆R/R₀)/%RH at RH 20% to 30%, RH 30% to 80%, and RH 80% to 90%, respectively. Additionally, a linear temperature change is observed with a sensitivity of −0.04 °C/%RH. The sensor also demonstrates a colorimetric temperature sensitivity of −82,036 K/%RH at RH 20% to 30% and −514 K/%RH at RH 30% to 90%, per captured image. Furthermore, real-time measurements of ethanol vapor with varying concentrations showcase the sensor’s applicability in gas sensing applications. Overall, we present a comprehensive exploration of the CIC sensor, emphasizing its design flexibility, electrical characteristics, and diverse sensing capabilities. The sensor’s potential applications extend to real-time environmental monitoring, highlighting its promising role in various gas sensing fields.

Epicuticular wax, the first protective film for numerous ground plant species, is crucial for modulating the evolution in plants. Since the waxy film is inherently thermoresponsive, many efforts focus on engineering materials for water/oil proofing, delivery, and collection, as well as microactuators by mimicking such film nature. Nonetheless, relatively fewer works address the mechanism of how the underlying substrates direct the reconstruction of waxy films while their temperature approaches the melting point. Here, we presented a strategy in which distinct frameworks of molten wax films could be examined among various substrates. Both “waxphobic” and “waxphilic” traits were first unveiled and could be achieved by the hydrophilic (water contact angle (WCA) = 42~82°) and hydrophobic (WCA = 109°) substrates, respectively. A theoretical model, based on experimental results, fluidic dynamics, and balance of surface energy, was developed to elucidate the above findings. Moreover, we demonstrated the above biomimetic epicuticular surface (BeSurface) can be applied for rewritable paper, erasable coding, and rehealable electronics without manual repairing. Remarkably, the healing time can be reduced down to 30 s, and the cycled folding test can be continued up to 500 times. All the new findings present the potentials of the BeSurface to improve the study of rehealable materials.