Skeletal muscle tissue represents an attractive powering component for biohybrid robots, as traditional actuators used in the soft robotic context often rely on complex mechanisms and lack scalability at small dimensions. This article proposes a monolithic biohybrid flexure mechanism actuated by a bioengineered skeletal muscle tissue. The design leverages the contractile properties of a bioengineered skeletal muscle to produce a bending motion in a monolithic, tubular mechanism made of a soft and biocompatible silicone blend. This structure integrates two cylindrical pillars that facilitate force transmission from the bioengineered muscle tissue. Performance assessments reveal excellent contractile and stable behavior upon electrical stimulation, compared to current biohybrid actuation systems, with enhanced performance as the mechanism's internal and external diameters decrease. Finite‐element simulations further reveal distinct force–displacement responses in mechanisms with different flexural rigidity. This innovative, scalable, and easy‐to‐fabricate design represents a significant step forward in the development of novel biohybrid machines.

Soft and flexible robotics is an emerging field that attracts a huge interest due to its ability to produce bioinspired devices that are easily adaptable to the environment. Biohybrid Machines (BHM) represent a category of soft robots that integrate biological tissues, such as engineered muscle tissues, as actuating systems. Although these devices present several advantages in some applications, their proper actuation still represents a challenge for researchers. This paper focuses on the development of a portable and programmable electrical stimulator designed to control muscle fiber-based biohybrid actuators. The stimulator, made using off-the-shelf components, was designed as a stacking of three independent printed circuit boards (PCBs), connected vertically in order to result in a final device with compact dimensions of 59 mm \(\times\) 28 mm \(\times\) 25 mm. The stimulation circuit is capable of delivering currents up to 18 mA with a voltage compliance of ± 90 V, and a power consumption of approximately 1.3 W. The device’s ability to induce twitch and tetanic contractions in a biohybrid actuator is demonstrated in different stimulation conditions. A practical application was also explored through a test case involving a flexible catheter prototype controlled by a biohybrid actuator, demonstrating its potential utility in a BHMs.

Free-standing, aligned electrospun PVA nanofiber membranes create a quasi-3D scaffold for C2C12 alignment. With Ziapin2 infiltration, visible light paces macroscopic contractions up to ∼460 µN (∼3.3 kPa) without genetics in vitro .

The integration of flexible organic electronics in soft robotic devices is a valuable way to enhance their functionality, towards augmented controllability and performance. Nonetheless, this field is generally unexplored. Here, we report a preliminary study on the integration of soft robotic components with Organic Field-Effect Transistor-based strain sensors. Such sensors will be tested as deformation transducer for bioengineered muscle tissues operating as biohybrid actuators. Moreover, the integration of ultra-flexible devices on catheter-like soft robotic supports is discussed.

Reliable storage and distribution are important for developing ready-to-use encapsulated cell products for transplantation and bioartificial liver applications. This study evaluated the cryopreservation of alginate-encapsulated HepaRG cells using a programmable controlled-rate freezing (CRF) protocol at −0.3 °C/min or conventional passive cooling at approximately −1 °C/min. Five media were tested: four commercial xeno-free formulations, including two DMSO-containing and two DMSO-free media, and a conventional formulation containing 90% fetal bovine serum and 10% DMSO. Following thawing and a 3-day recovery period, metabolic activity, albumin secretion, ammonia and lactate clearance, and phase I and phase II biotransformation activities were assessed. Cryopreservation reduced metabolic activity relative to non-frozen controls, but key hepatic functions remained detectable. The tested CRF protocol generally yielded equal or higher functional values than conventional freezing. Medium performance varied according to the endpoint assessed. Within CRF, CryoStor CS10 produced relatively high mean PrestoBlue and albumin secretion values, whereas Cellvation produced the highest mean CYP1A1/1A2 activity. These product-specific observations do not establish a general effect of DMSO. The findings support the short-term feasibility of the tested CRF protocol for this encapsulated HepaRG model but not broader clinical or drug-testing applications.

The development of sensing elements capable of direct and real‐time monitoring is fundamental to the actual exploitation of soft robotic systems in real application scenarios. In this paper, the integration of an electronic strain sensor based on an ultra‐flexible, all‐organic field‐effect transistor on a soft structure, conceived for future application as a soft robotic catheter in drug delivery, is reported. The device, entirely fabricated by means of cost‐effective, large area processes, is developed over a sub‐micrometrical, biocompatible substrate, with mechanical properties compatible with soft robotic production. Electrical performance of the transistor is characterized, showing the suitability of the device parameters to the envisaged application in terms of low power consumption and reproducibility. A successful integration of the ultra‐flexible transistor platform into the soft robotic system is demonstrated. A thorough electromechanical characterization of the sensorized system is provided, showing a programmable sensitivity to mechanical deformation in the range 5°–30°, based on the overthreshold conditions imposed by the transistor gate voltage. The results pave the way for the effective exploitation of organic flexible electronics as a valuable solution for the development of sensorized soft robots, toward a complete observability and controllability of their actuation in operation scenarios.