An electroactive scaffold integrated with noninvasive in vivo electrical-stimulation (ES) capability shows great promise in the repair and regeneration of damaged tissues. Developing high-performance piezoelectric biomaterials which can simultaneously serve as both a biodegradable tissue scaffold and controllable electrical stimulator remains a great challenge. Herein, we constructed a biodegradable high-performance 3D piezoelectric scaffold with ultrasound (US)-driven wireless ES capability, and demonstrated its successful application for the repair of spinal cord injuries in a rat model. The 3D multichannel piezoelectric scaffold was prepared by electrospinning of poly(lactic acid) (PLA) nanofibers incorporated with biodegradable high-performance piezoelectric potassium sodium niobate (K0.5Na0.5NbO3, KNN) nanowires. With programmed US irradiation as a remote mechanical stimulus, the on-demand in vivo ES with an adjustable timeline, duration, and strength can be delivered by the 3D piezoelectric scaffold. Under proper US excitation, the 3D tissue scaffolds made of the piezoelectric composite nanofibers can accelerate the recovery of motor functions and enhance the repair of spinal cord injury. The immunohistofluorescence investigation indicated that the 3D piezoelectric scaffolds combined with the US-driven in vivo ES promoted neural stem cell differentiation and endogenous angiogenesis in the lesion. This work highlights the potential application of a biodegradable high-performance piezoelectric scaffold providing US-driven on-demand electrical cues for regenerative medicine.

Wirelessly Powered Electrical-Stimulation Based on Biodegradable 3D Piezoelectric Scaffolds Promotes the Spinal Cord Injury Repair.

Abstract Versatile strategies have been developed to construct electrospun fiber-based drug delivery systems for tissue regeneration and cancer therapy. We first introduce the construction of electrospun fiber scaffolds and their various structures, as well as various commonly used types of drugs. Then, we discuss some representative strategies for controlling drug delivery by electrospun fibers, with specific emphasis on the design of endogenous and external stimuli-responsive drug delivery systems. Afterwards, we summarize the recent progress on controlling drug delivery with electrospun fiber scaffolds for tissue engineering, including soft tissue engineering (such as skin, nerve, and cardiac repair) and hard tissue engineering (such as bone, cartilage, and musculoskeletal systems), as well as for cancer therapy. Furthermore, we provide future development directions and challenges facing the use of electrospun fibers for controlled drug delivery, aiming to provide insights and perspectives for the development of smart drug delivery platforms and improve clinical therapeutic effects in tissue regeneration and cancer therapy. Graphical abstract 

https://link.springer.com/content/pdf/10.1007/s42765-022-00198-9.pdf

Electrospun Fibers Control Drug Delivery for Tissue Regeneration and Cancer Therapy

Ultrasound-driven in vivo electrical stimulation based on biodegradable piezoelectric nanogenerators for enhancing and monitoring the nerve tissue repair

Recently, bioelectronic devices extensively researched and developed through the convergence of flexible biocompatible materials and electronics design that enables more precise diagnostics and therapeutics in human health care and opens up the potential to expand into various fields, such as clinical medicine and biomedical research. To establish an accurate and stable bidirectional bio‐interface, protection against the external environment and high mechanical deformation is essential for wearable bioelectronic devices. In the case of implantable bioelectronics, special encapsulation materials and optimized mechanical designs and configurations that provide electronic stability and functionality are required for accommodating various organ properties, lifespans, and functions in the biofluid environment. Here, this study introduces recent developments of ultra‐thin encapsulations with novel materials that can preserve or even improve the electrical performance of wearable and implantable bio‐integrated electronics by supporting safety and stability for protection from destruction and contamination as well as optimizing the use of bioelectronic systems in physiological environments. In addition, a summary of the materials, methods, and characteristics of the most widely used encapsulation technologies is introduced, thereby providing a strategic selection of appropriate choices of recently developed flexible bioelectronics.

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/advs.202202980

Ultra‐Thin Flexible Encapsulating Materials for Soft Bio‐Integrated Electronics

Peripheral nerve regeneration and functional recovery is a major challenge in clinical practice. Nerve conduit is an effective treatment for peripheral nerve repair, but the traditional hollow nerve conduit is not satisfactory in peripheral nerve repair due to the limitation of cell migration and nutrient transport. Herein, the double cross‐linked hydrogels with injectable, self‐healing, and conductive properties are synthesized by the Schiff base reaction between polyaniline‐modified carboxymethyl chitosan and aldehyde‐modified Pluronic F‐127 (F127‐CHO), and the hydrophobic interaction of F127‐CHO. The conductive hydrogel is injected into the cavity of chitosan conduit prepared by electrodeposition. The inner conductive hydrogel and the outer chitosan conduit are formed into a whole through the Schiff base reaction to obtain a double‐layer composite hydrogel nerve conduit. The double‐layer composite hydrogel neural conduit loaded with 7,8‐dihydroxyflavone (DHF) has excellent degradability, biocompatibility, antioxidant activity, and Schwann cell proliferation activity. In the rat sciatic nerve defect model, the double‐layer composite hydrogel nerve conduit significantly promotes sciatic nerve regeneration compared with the chitosan hollow conduit. Surprisingly, the repair ability of double‐layered hydrogel nerve conduit loaded with DHF is comparable to that of autologous transplantation. Therefore, this multifunctional double‐layer composite hydrogel conduit has great potential for peripheral nerve repairing.

Multifunctional Double‐Layer Composite Hydrogel Conduit Based on Chitosan for Peripheral Nerve Repairing

The long-segment peripheral nerve injury (PNI) represents a global medical challenge, leading to incomplete nerve tissue recovery and unsatisfactory functional reconstruction. However, the current electrical stimulation (ES) apparatuses fail perfect nerve repair due to their inability of the variable synchronous self-regulated function with physiological states. It is urgent to develop an implantable ES platform with physiologically adaptive function to provide instantaneous and nerve-preferred ES. Here, a physiologically self-regulated electrical signal is generated by integrating a novel tribo/piezoelectric hybrid nanogenerator with a nanoporous nerve guide conduit to construct a fully implantable neural electrical stimulation (FI-NES) system. The optimal neural ES parameters completely originate from the body itself and are highly self-responsive to different physiological states. The morphological evaluation, representative protein expression level, and functional reconstruction of the regenerated nerves are conducted to assess the PNI recovery process. Evidence shows that the recovery effect of 15 mm length nerve defects under the guidance of the FI-NES system is significantly close to the autograft. The designed FI-NES system provides an effective method for long-term accelerating the recovery of PNI in vivo and is also appropriate for other tissue injury or neurodegenerative diseases.

Physiologically Self-Regulated, Fully Implantable, Battery-Free System for Peripheral Nerve Restoration

Invasive electrical stimulation (iES) is prone to cause neural stimulus-inertia owing to its excessive accumulation of exogenous charges, thereby resulting in many side effects and even failure of nerve regeneration and functional recovery. Here, a wearable neural iES system is well designed and built for bionic and long-lasting neural modulation. It can automatically yield biomimetic pulsed electrical signals under the driven of respiratory motion. These electrical signals are full of unique physiological synchronization can give biofeedback to respiratory behaviors, self-adjusting with different physiological states of the living body, and thus realizing a dynamic and biological self-matched modulation of voltage-gated calcium channels on the cell membrane. Abundant cellular and animal experimental evidence confirm an effective elimination of neural stimulus-inertia by these bioelectrical signals. An unprecedented nerve regeneration and motor functional reconstruction are achieved in long-segmental peripheral nerve defects, which is equal to the gold standard of nerve repair -- autograft. The wearable neural iES system provides an advanced platform to overcome the common neural stimulus-inertia and gives a broad avenue for personalized iES therapy of nerve injury and neurodegenerative diseases. 

/pdf/biofeedback-electrostimulation-for-bionic-and-long-lasting-1vkno2ls.pdf

Biofeedback electrostimulation for bionic and long-lasting neural modulation

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Qi Wu

Author Tools

Chat about Author

Papers

Physiologically Self-Regulated, Fully Implantable, Battery-Free System for Peripheral Nerve Restoration

Biofeedback electrostimulation for bionic and long-lasting neural modulation