Durable Flexible Conductive Fiber Based on Cross-Linking Network Tannic Acid/Polypyrrole for Wearable Thermotherapy Monitoring System.

Intelligent wearable textiles have garnered attention and advancement, particularly in the realms of thermotherapy and health monitoring. As a critical component of intelligent wearable textiles, conductive fibers are expected to have long-term stable and durable conductivity. In this work, a highly stretchable and conductive fiber based on tannic acid/polypyrrole was developed.

Bioinspired Asymmetric Polypyrrole Membranes with Enhanced Photothermal Conversion for Highly Efficient Solar Evaporation.

Solar-driven interfacial evaporation (SDIE) has attracted great attention by offering a zero-carbon-emission solution for clean water production. The manipulation of the surface structure of the evaporator markedly promotes the enhancement of light capture and the improvement of evaporation performance. Herein, inspired by seedless lotus pod, a flexible pristine polypyrrole (PPy) membrane with macro/micro-bubble and nanotube asymmetric structure is fabricated through template-assisted interfacial polymerization.

A multifunctional surgical suture with electroactivity assisted by oligochitosan/gelatin-tannic acid for promoting skin wound healing and controlling scar proliferation.

Surgical wound closure is accomplished most frequently with sutures, optimally proceeding rapidly and without complication. However, surgical sutures can trigger foreign body reactions and incite abnormal collagen deposition. Sustained inflammation can result in abnormal wound healing with hypertrophic scar formation.

Turning waste into valuables: deposition of polypyrrole on the obsolete mask for Cr(VI) removal and desalination.

The global mask consumption has been exacerbated because of the coronavirus disease 2019 (COVID-19) pandemic. Simultaneously, the traditional mask disposal methods (incineration and landfill) have caused serious environmental pollution and waste of resources. Herein, a simple and green mass-production method has been proposed to recycle carbon protective mask (CPM) into the carbon protective mask/polydopamine/polypyrrole (CPM/PDA/PPy) composite by polymerization of PPy.

Conductive fibers for biomedical applications.

Bioelectricity has been stated as a key factor in regulating cell activity and tissue function in electroactive tissues. Thus, various biomedical electronic constructs have been developed to interfere with cell behaviors to promote tissue regeneration, or to interface with cells or tissue/organ surfaces to acquire physiological status electrical signals. Benefiting from the outstanding advantages of flexibility, structural diversity, customizable mechanical properties, and tunable distribution of conductive components, conductive fibers are able to avoid the damage-inducing mechanical mismatch between the construct and the biological environment, in return to ensure stable functioning of such constructs during physiological deformation.

Maple Leaf Inspired Conductive Fiber with Hierarchical Wrinkles for Highly Stretchable and Integratable Electronics.

Stretchable and durable conductors are significant to the development of wearable devices, robots, human-machine interfaces, and other artificial intelligence products. However, the desirable strain-insensitive conductivity and low hysteresis are restricted by the failure of stretchable structures and mismatch of mechanical properties (rigid conductive layer and elastic core substrate) under large deformation. Here, based on the principles of fractal geometry, a stretchable conductive fiber with hierarchical wrinkles inspired by the unique shape of the maple leaf was fabricated by combining surface modification, interfacial polymerization, and improved prestrain finishing methods to break through this dilemma.

A honeybee stinger-inspired self-interlocking microneedle patch and its application in myocardial infarction treatment.

Weak tissue adhesion remains a major challenge in clinical translation of microneedle patches. Mimicking the structural features of honeybee stingers, stiff polymeric microneedles with unidirectionally backward-facing barbs were fabricated and embedded into various elastomer films to produce self-interlocking microneedle patches. The spirality of the barbing pattern was adjusted to increase interlocking efficiency.

Flexible and easy-handling pristine polypyrrole membranes with bayberry-like vesicle structure for enhanced Cr(VI) removal from aqueous solution.

Polypyrrole has been extensively explored for Cr(VI) removal from wastewater towing to the advantages of superior performance, low cost, facile synthesis, and high environmental stability. However, the unsatisfactory adsorption capacity and complicated process of adsorbent separation from aqueous solutions remain a huge challenge, limiting its practical application. Herein, a flexible PPy membrane with bayberry-like vesicle structures (PPy-B) was prepared via template-assisted interfacial polymerization.

A biocompatible polypyrrole membrane for biomedical applications.

Polypyrrole (PPy) is the most widely investigated electrically conductive biomaterial. However, because of its intrinsic rigidity, PPy has only been used either in the form of a composite or a thin coating. This work presents a pure and soft PPy membrane that is synergically reinforced with the electrospun polyurethane (PU) and poly-l-lactic acid (PLLA) fibers.

Chitosan/gelatin-tannic acid decorated porous tape suture with multifunctionality for tendon healing.

The inferior tendon healing after surgery is inextricably linked to the surgical suture. Poor load transfer along the suture often results in a high tendon re-tear rate. Besides, the severe inflammation and infection induced by sutures even cause a second surgery.

Influence of polyethylene terephthalate/ polyamide (PET/PA) bilayer structure on physical and strength-related properties of superpressure angioplasty balloons.

Background: Percutaneous transluminal coronary angioplasty (PTCA), including balloon angioplasty, is a standard clinical invasive treatment for coronary artery disease. The coronary lesion with calcification is difficult to dilate and the prevention of balloon failure is especially important.

Objective: A novel superpressure balloon was fabricated with bilayered structure of polyethylene terephthalate (PET) and PA12 (polyamide).

Conductive biomaterials for cardiac repair: A review.

Myocardial infarction (MI) is one of the fatal diseases in humans. Its incidence is constantly increasing annually all over the world. The problem is accompanied by the limited regenerative capacity of cardiomyocytes, yielding fibrous scar tissue formation.

An enhanced periosteum structure/function dual mimicking membrane forrestorations of periosteum and bone.

Periosteum plays a pivotal role in bone formation and reconstruction. The ideal repair process for critical-size bone defects with periosteum damage is to induce regeneration of periosteum tissue and the subsequent bone regeneration derived by the periosteum. Inspired by the bilayer structure of the natural periosteum, we develop a periosteum structure/function dual mimicking membrane for therestoration of periosteum and bone tissue.

Design of Electro-Thermal Glove with Sensor Function for Raynaud's Phenomenon Patients.

Raynaud's phenomenon (RP) is a disease that mainly affects human fingertips during cold weather. It is difficult to treat this disease using medicine, apart from keeping the body in a warm environment. In this research, conductive knitted fabrics were fabricated to help relax the vessels of the patient's fingertips by providing proper heat, and also serving as a sensor to detect finger motion after relaxation of the blood vessels of patients.

Construction and application of textile-based tissue engineering scaffolds: a review.

Tissue engineering (TE) provides a practicable method for tissue and organ repair or substitution. As the most important component of TE, a scaffold plays a critical role in providing a growing environment for cell proliferation and functional differentiation as well as good mechanical support. And the restorative effects are greatly dependent upon the nature of the scaffold including the composition, morphology, structure, and mechanical performance.

Limb salvage after aneurysmal degeneration of a cryopreserved vein allograft: Searching the autologous veins of the arm is worth the effort.

Clinical Data: We hereby report a case of limb salvage involving a 64-year-old man who was hospitalized with ischemic foot ulcers for two months. Endarterectomy with patching and stenting of the left iliofemoral artery failed. A composite bypass of two segments of the endarterectomized superficial femoral artery and a cryopreserved saphenous vein graft was implanted one week later.

Long-term anticoagulation and selective cells adhesion surface via combination of covalent grafting and layer by layer assembly.

Surface modification by long-term active component is essential for biocompatible polymers-based vascular grafts to prevent thrombus formation and reduce intimal hyperplasia. In this study, a simple approach was developed to immobilize bioactive heparin to the surface of ε-polycaprolactone (PCL) grafts through a two-step strategy combining covalent grafting and layer by layer assembly of polyelectrolytes. The performance of heparinized PCL was evaluated in vitro, including the release behavior of heparin, anticoagulation and different types of cells adhesion characteristic.

Donkey pericardium compares favorably with commercial xenopericardia used in the manufacture of transcatheter heart valves.

Transcatheter aortic valve implantation (TAVI) has gained considerable acceptance in the past decade due to its lower risks than conventional open-heart surgery. However, the deformation and delamination of the leaflets during the crimping procedure have raised questions about the durability and long-term serviceability of the pericardium tissue from which the leaflets are made. The collagen architecture, wall thickness and mechanical properties of donkey pericardium were investigated to assess its suitability as an alternative material for the manufacture of heart valves.

Surface modification by assembling: a modular approach based on the match in nanostructures.

Quantitative co-immobilization of multiple bioactive proteins or diverse chemical moieties on a surface is challenging because of the competition among the reactants. In this work, a two-step method is proposed, in which each type of reactant is firstly grafted onto the surface of functional nanoparticles, and then these nanoparticles are mixed and cast onto a substrate that has an appropriate nano-topography to trap and immobilize the nanoparticles. This approach has two distinct advantages: (1) it avoids competition among reactants of different natures; (2) the nanoparticles prepared in the first step can be physically mixed at the desired quantity and time and with the desired type.

Polypyrrole as Electrically Conductive Biomaterials: Synthesis, Biofunctionalization, Potential Applications and Challenges.

Electrical phenomenon is ubiquitous in any biological system. However, most synthetic biomaterials are insulators to either electrical or ionic current. To mimic the electrical and ionic conductivities of natural tissues, electrically conductive polymers have been studied and are becoming a new class of biomaterials.

Conductive Polymer Waving in Liquid Nitrogen.

The poor mechanical properties and processability of pristine heterocyclic conductive polymers represent the most notable scientific and technological challenges that have greatly limited the application of these polymers. We report a soft and mechanically processable free-standing pristine polypyrrole (PPy) membrane (PPy-N) that is as soft in liquid nitrogen (-196 °C) as it is at room temperature, despite a glass transition temperature (T) above 100 °C. This PPy membrane also displays a highly attractive combination of properties, including mechanical processability, lightweight (9 g m), large surface area (14.

One-step reactivity-driven synthesis of core-shell structured electrically conducting particles for biomedical applications.

Electrically conductive and functional polymeric nanoparticles have significant potential in biomedical applications such as in sensing and stimulation. Polymeric core-shell particles are usually prepared either through a multiple-step process or by the design of amphiphilic macromolecules. Here we report a simple one-step and one-pot emulsion polymerization method to synthesize the core-shell structured electrically conducting polymer particles based on the difference in comonomer reactivity.

Chitosan-Coated Collagen Membranes Promote Chondrocyte Adhesion, Growth, and Interleukin-6 Secretion.

Designing scaffolds made from natural polymers may be highly attractive for tissue engineering strategies. We sought to produce and characterize chitosan-coated collagen membranes and to assess their efficacy in promoting chondrocyte adhesion, growth, and cytokine secretion. Porous collagen membranes were placed in chitosan solutions then crosslinked with glutaraldehyde vapor.

Enhanced osteogenic differentiation of mesenchymal stem cells on poly(L-lactide) nanofibrous scaffolds containing carbon nanomaterials.

Carbon nanomaterials (CNMs), such as carbon nanotube (CNT) and graphene, are highlighted in bone regeneration because of their osteoinductive properties. Their combinations with nanofibrous polymeric scaffolds, which mimic the morphology of natural extracellular matrix of bone, arouse keen interest in bone tissue engineering. To this end, CNM were incorporated into nanofibrous poly(L-lactic acid) scaffolds by thermal-induced phase separation.