The tendon–bone interface has a complex gradient
structure
vital for stress transmission and pressure buffering during movement.
However, injury to the gradient tissue, especially the tendon and
cartilage components, often hinders the complete restoration of the
original structure. Here, a metal ion network hydrogel scaffold, with
the capability of targeting multitissue, was constructed through the
photopolymerization of the LHERHLNNN peptide-modified zeolitic imidazolate
framework-8 (LZIF-8) and the WYRGRL peptide-modified magnesium metal–organic
framework (WMg-MOF) within the hydrogel scaffold, which could facilitate
the directional migration of metal ions to form a dynamic gradient,
thereby achieving integrated regeneration of gradient tissues. LZIF-8
selectively migrated to the tendon, releasing zinc ions to enhance
collagen secretion and promoting tendon repair. Simultaneously, WMg-MOF
migrated to cartilage, releasing magnesium ions to induce cell differentiation
and facilitating cartilage regeneration. Infrared spectroscopy confirmed
successful peptide modification of nano ZIF-8 and Mg-MOF. Fluorescence
imaging validated that LZIF-8/WMg-MOF had a longer retention, indirectly
confirming their successful targeting of the tendon–bone interface.
In summary, this dual-targeted metal ion network hydrogel scaffold
has the potential to facilitate synchronized multitissue regeneration
at the compromised tendon–bone interface, offering favorable
prospects for its application in the integrated reconstruction characterized
by the gradient structure