A Hydro-Expansive and Degradable Biomaterial Enabling Shape Recovery of Film-Based Devices in Biofluids.

Hygroscopic actuation is an important material function, which enables a broad range of applications such as self-healing devices, soft robotics, and catheter implantation. With the current paradigm of implantable devices shifting toward soft and tissue-mimicking systems, this function however, is particularly weak in soft- and bio-materials due to the rapid loss of intermolecular interactions upon water incorporation. Here, a chitosan-based bio-composite is developed, which sustains the intermolecular repulsive force during water absorption through synergistic effects of hydrogen bonding, plasticization, and nano-confinement.

Materials Advancements for the Safety and Patency of Implantable Cardiovascular Devices.

Implantable cardiovascular devices have revolutionized the management of cardiovascular diseases, significantly enhancing patients' quality of life. With the increasing demand of cardiac implantable electronic devices, the imperative for novel device development is evident. This review article first elaborates the mechanisms underlying foreign body response and infection, elucidating the complex interplay between implanted constructs and host tissues.

Inhibitory effects on smooth muscle cell adhesion and proliferation due to oscillating electric fields by nanogenerators.

A common complication of the removal of atherosclerotic plaques or thrombi deposits to restore blood flow is restenosis. It is known that the excessive adhesion and proliferation of smooth muscle cells (SMCs) is the primary reason for restenosis. In this work, we conducted an study to show that a weak oscillating electric field (EF) generated by a mechanically-driven nanogenerator could prohibit SMC adhesion and proliferation on a substrate surface.

3D-Printed Piezoelectric Stents for Electricity Generation Driven by Pressure Fluctuation.

Vascular stenting is a common procedure used to treat diseased blood vessels by opening the narrowed vessel lumen and restoring blood flow to ischemic tissues in the heart and other organs. In this work, we report a novel piezoelectric stent featuring a zigzag shape fabricated by fused deposition modeling three-dimensional (3D) printing with a built-in electric field. The piezoelectric composite was made of potassium sodium niobite microparticles and poly(vinylidene fluoride--hexafluoropropylene), complementing each other with good piezoelectric performance and mechanical resilience.

Development of Ferroelectric P(VDF-TrFE) Microparticles for Ultrasound-Driven Cancer Cell Killing.

Current breast cancer treatments involve aggressive and invasive methods, leaving room for new therapeutic approaches to emerge. In this work, we explore the possibility of using piezoelectric [P(VDF-TrFE)] microparticles (MPs) as a source of inducing irreversible electroporation (IRE) of 4T1 breast cancer cells. We detail the MP formation mechanism and size control and subsequent characterizations of the as-synthesized MPs which confirms the presence of piezoelectric β-phase.

Stretchable piezoelectric biocrystal thin films.

Stretchability is an essential property for wearable devices to match varying strains when interfacing with soft tissues or organs. While piezoelectricity has broad application potentials as tactile sensors, artificial skins, or nanogenerators, enabling tissue-comparable stretchability is a main roadblock due to the intrinsic rigidity and hardness of the crystalline phase. Here, an amino acid-based piezoelectric biocrystal thin film that offers tissue-compatible omnidirectional stretchability with unimpaired piezoelectricity is reported.

Stretchable Encapsulation Materials with High Dynamic Water Resistivity and Tissue-Matching Elasticity.

Flexible implantable medical devices (IMDs) are an emerging technology that may substantially improve the disease treatment efficacy and quality of life of patients. While many advancements have been achieved in IMDs, the constantly straining application conditions impose extra requirements for the packaging material, which needs to retain both high stretchability and high water resistivity under dynamic strains in a physiological environment. This work reports a polyisobutylene (PIB) blend-based elastomer that simultaneously offers a tissue-like elastic modulus and excellent water resistivity under dynamic strains.