Injectable, Self‐Contained, Subaqueously Cross‐Linking Laminous Adhesives for Biophysical‐Chemical Modulation of Osteochondral Microenvironment

Abstract

Current osteochondral (OC) defect repair approaches using premade scaffolds face clinical limitations due to invasiveness, weak integrity, and/or insufficient interfacial bonding. An injectable hydrophobic laminous adhesive is developed that rapidly photocross‐link subaqueously and forms robust bi‐layered structure that orchestrates biophysical‐chemical cues for stimulating OC repair. Liquid hydrophobic photo‐cross‐linkable poly (lactide‐co‐propylene glycol‐co‐lactide) dimethacrylates (PmLnDMA) are adopted as cartilage phase and PmLnDMA encapsulating methacrylated hydroxyapatite nanoparticles (PmLnDMA/MH) as the mineralized subchondral bone phase. Both phases exhibit strong interfacial bonding due to the presence of “CC”. Mechanotransduction and growth factor‐mediated signaling pathways are enchanced by matching the mechanical properties of two phases to native cartilage and bone via systematical modulation of the adhesives’ composition and encapsulated growth factors’ release profile. This enhances mesenchymal stem cells’ commitment to corresponding chondrocytes and osteoblasts to augment OC repair in vitro and in vivo, and ultimately benefits patients suffering from OC fracture, osteoarthritis, and osteoporosis.

A differential-targeting core–shell microneedle patch with coordinated and prolonged release of mangiferin and MSC-derived exosomes for scarless skin regeneration

“…We previously demonstrated that this configuration possesses excellent in vitro and in vivo biocompatibility, capability to encapsulate and release bioactive macromolecules in the long term, and appropriate mechanical properties (with a compressive modulus of 50 MPa). 24–28 The synthesized P 7 L 2 DMA was characterized by 1 H NMR, which is similar to the previous data, and confirmed as P 7 L 1.95 1.8MA (data not shown).…”

“…Moreover, the P 7 L 2 DMA in the microneedle substrate, which covers the entire wound, exhibits significant hydrophobicity as demonstrated in our previous research. 24,27 When crosslinked, it forms a dense polymer network with a low water vapor transmission rate, effectively preserving the wound moisture and complementing the hydrating properties of GelMA. In conclusion, the combination of the GelMA shell and the P 7 L 2 DMA substrate design synergistically maintains wound moisture, resulting in a beneficial hydration effect.…”

Enhanced hyaline cartilage formation and continuous osteochondral regeneration via 3D-Printed heterogeneous hydrogel with multi-crosslinking inks

“…8 G). The Hedgehog and TGF-β pathways have been widely reported to be associated with the process of cartilage development [ 45 , 46 ], while the Wnt and cAMP signaling pathways are reportedly associated with osteogenesis in the corresponding literature [ 47 , 48 ]. KEGG pathway analysis showed that the Hedgehog signaling pathway was more significant than the other pathways, indicating that the difference between the G-dNC/nHA and control groups was reflected in chondrogenesis.…”

Degradable Nanohydroxyapatite-Reinforced Superglue for Rapid Bone Fixation and Promoted Osteogenesis

“…In situ formation of nHAP-embedded polymer networks enable adhesion through mechanical interlocking or functional groups on the polymer chains. 16,30 However, the adhesion strength is insufficient for bone tissues due to the poor mechanical properties of the polymer matrix, and it often undergoes lengthy cross-linking and elaborate presynthesis. 17,31 Drawing inspiration from the inorganic−organic structure of natural bone, herein, we fabricated a nHAP-reinforced osteogenic backbone-degradable superglue (O-BDSG) by utilizing in situ rROP, to simultaneously achieve robust bone adhesion and osteogenic bioactivity without impairing degradability.…”

“…However, further applications in bone fracture treatment are limited due to a lack of adhesion to bone tissues. In situ formation of nHAP-embedded polymer networks enable adhesion through mechanical interlocking or functional groups on the polymer chains. , However, the adhesion strength is insufficient for bone tissues due to the poor mechanical properties of the polymer matrix, and it often undergoes lengthy cross-linking and elaborate presynthesis. , …”