Ultrasound-triggered gelation for restoring biomechanical properties of degenerated functional spinal units
Author(s)
Type
Journal Article
Abstract
Lower back pain is closely associated with intervertebral disc (IVD) degeneration and is a leading cause of global disability. Existing treatment options are unable to provide suitable long-term outcomes, and emerging strategies employing injectable biomaterials are hindered by factors including limited native tissue integration and depth- or time-constrained gelation mechanisms. To overcome these issues, the present research evaluates a new concept employing ultrasound to remotely trigger in situ implant formation. The concept centers around an implant precursor biomaterial consisting of an anionic polysaccharide solution containing thermally sensitive liposomes loaded with ionic crosslinkers. Ultrasound-mediated heating to 4–5 °C above normal body temperature triggers liposomal release of the crosslinking species, thereby initiating hydrogel formation. Optimization studies define the implant precursor material (1.5% wt/v sodium alginate seeded with calcium-loaded liposomes (10–15 mm calcium chloride) and 6% wt/v glass microspheres) and the ultrasound parameters (0.95 MHz, 1.6 MPa amplitude, 87% duty cycle). Proof-of-concept experiments in degenerated ex vivo bovine IVDs indicate partial restoration of biomechanical function, with the implanted biomaterial well-integrated into the disc tissue and without material herniation. These results offer promise for treating intervertebral disc degeneration, with continued refinement of biomaterials and protocols being essential for achieving robust in-disc efficacy.
Date Issued
2026-02-16
Date Acceptance
2025-12-01
Citation
Advanced healthcare materials, 2026, 15 (7)
ISSN
2192-2640
Publisher
Wiley
Journal / Book Title
Advanced healthcare materials
Volume
15
Issue
7
Copyright Statement
© 2025 The Author(s). Advanced Healthcare Materials published by Wiley-VCH GmbH This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/41376295
Subjects
ANULUS FIBROSUS
BACK-PAIN
BIOCOMPATIBLE MATERIAL
biomechanics
CALCIUM ALGINATE GEL
Engineering
Engineering, Biomedical
FOCUSED ULTRASOUND
hydrogel
intervertebral disc
INTERVERTEBRAL DISC
LUMBAR
Materials Science
Materials Science, Biomaterials
Nanoscience & Nanotechnology
NUCLEUS PULPOSUS
Science & Technology
Science & Technology - Other Topics
spine
STEM-CELLS
Technology
TEMPERATURE-SENSITIVE LIPOSOMES
ultrasound
Publication Status
Published
Coverage Spatial
Germany
Article Number
e01823
Date Publish Online
2025-12-10