Researchers have unveiled a pioneering "bone bandage" that not only regenerates damaged bones in mice but also holds the promise of transforming bone regeneration in humans.
Developed by scientists at the Korea Advanced Institute of Science and Technology (KAIST), this biomimetic scaffold combines piezoelectric materials and the growth-promoting properties of hydroxyapatite (HAp), a naturally occurring mineral found in bones.
The innovative approach KAIST researchers took, although very much sounding like science fiction, is simply a freestanding scaffold that generates electrical signals when pressure is applied.
Piezoelectric materials, which generate an electric charge in response to mechanical stress, have long been known to play a role in bone repair. However, the integration of HAp takes this concept to a whole new level.
Hydroxyapatite, a mineral already known for its role in enhancing bone strength and regeneration, has been used in various applications, from toothpaste to fortify teeth to biomaterials for bone grafts. The researchers combined HAp with polyvinylidene fluoride-co-trifluoro ethylene (P(VDF-TrFE)), a polymer film, to create a scaffold with piezoelectric properties and a surface mimicking the body's extracellular matrix.
Comparisons between scaffolds with and without HAp in simulated environments revealed impressive results. Cell attachment on HAp scaffolds was 10% to 15% higher, and after five days of cell culture, cell proliferation was 20% to 30% higher.
Additionally, levels of osteogenesis – the process of bone formation – were approximately 30% to 40% higher on the HAp scaffolds, suggesting that HAp could enhance the scaffold's piezoelectric properties and create an environment conducive to tissue regeneration.
Significant regeneration after six weeks of scaffolds on bone defects
The real test came when the researchers implanted their HAp/P(VDF-TrFE) scaffolds in mice with skull bone defects. The scaffolds were left in place for six weeks without deformation, and the results were remarkable.
The mice with HAp scaffolds exhibited significantly enhanced bone regeneration compared to the control groups, with no adverse events such as infection or inflammatory responses observed.
Seungbum Hong, one of the study's corresponding authors, expressed excitement about the development, stating, "We have developed a HAp-based piezoelectric composite material that can act like a 'bone bandage' through its ability to accelerate bone regeneration."
This research not only opens new doors for biomaterial design but also explores the potential impact of piezoelectricity and surface properties on bone regeneration.
The study, published in the journal ACS Applied Materials & Interfaces, marks a significant leap forward in the field of regenerative medicine.
Study Abstract
Bone regeneration remains a critical concern across diverse medical disciplines because it is a complex process that requires a combinatorial approach involving the integration of mechanical, electrical, and biological stimuli to emulate the native cellular microenvironment. In this context, piezoelectric scaffolds have attracted considerable interest owing to their remarkable ability to generate electric fields in response to dynamic forces. Nonetheless, the application of such scaffolds in bone tissue engineering has been limited by the lack of a scaffold that can simultaneously provide both the intricate electromechanical environment and the biocompatibility of the native bone tissue. Here, we present a pioneering biomimetic scaffold that combines the unique properties of piezoelectric and topographical enhancement with the inherent osteogenic abilities of hydroxyapatite (HAp). Notably, the novelty of this work lies in the incorporation of HAp into polyvinylidene fluoride-co-trifluoro ethylene in a freestanding form, leveraging its natural osteogenic potential within a piezoelectric framework. Through comprehensive in vitro and in vivo investigations, we demonstrate the remarkable potential of these scaffolds to accelerate bone regeneration. Moreover, we demonstrate and propose three pivotal mechanisms─(i) electrical, (ii) topographical, and (iii) paracrine─that collectively contribute to the facilitated bone healing process. Our findings present a synergistically derived biomimetic scaffold design with wide-ranging prospects for bone regeneration as well as various regenerative medicine applications.
Originally published on Interesting Engineering : Original article