Reinforced Supramolecular Hydrogels from Attapulgite and Cyclodextrin Pseudopolyrotaxane for Sustained Intra‐Articular Drug Delivery

Abstract

Injectable hydrogels for nonsteroidal anti‐inflammatory drugs’ (NSAIDs) delivery to minimize the side effects of NSAIDs and achieve long‐term sustained release at the targeted site of synovial joint are attractive for osteoarthritis therapy, but how to improve its mechanical strength remains a challenge. In this work, a kind of 1D natural clay mineral material, attapulgite (ATP), is introduced to a classical cyclodextrin pseudopolyrotaxane (PPR) system to form a reinforced supramolecular hydrogel for sustained release of diclofenac sodium (DS) due to its rigid, rod‐like morphology, and unique structure, which has great potential in tissue regeneration, repair, and engineering. Investigation on the interior morphology and rheological property of the obtained hydrogel points out that the ATP distributed in PPR hydrogel plays a role similar to the “reinforcement in concrete” and exhibits a positive effect on improving the mechanical properties of PPR hydrogel by regulating their interior morphology from a randomly distributed style to the well‐ordered porous frame structure. The hybrid hydrogels demonstrate good shear‐thinning and thixotropic properties, excellent biocompability, and sustained release behavior both in vitro and in vivo. Furthermore, preliminary in vivo treatment in an acute inflammatory rat model reveals that the ATP hybrid hydrogels present sustained anti‐inflammatory effect.

Bioinspired Hydroxyapatite Coating Infiltrated with a Graphene Oxide Hybrid Supramolecular Hydrogel Orchestrates Antibacterial and Self-Lubricating Performance

“…The morphology of the freeze-dried hybrid hydrogel was investigated by scanning electron microscopy (SEM), and a native hydrogel (without GO, GO 0 PEG 16 CD 60 ) was also observed as comparison. As shown in Figure D,E, the inner morphology of hydrogels was changed from irregular porous aggregates to a sheet-like multilayer structure, which suggested that the introduction of GO sheets can provide a unique 2D constant cross-linkers to construct and stabilize the three-dimensional (3D) networks. , …”

Polycaprolactone/Gelatin/Hydroxyapatite Electrospun Nanomembrane Materials Incorporated with Different Proportions of Attapulgite Synergistically Promote Bone Formation

“…[54][55][56][57][58] In addition, ATP has a large specific surface area and strong adsorption capacity and can absorb growth factors and nutrients in the surrounding tissues, which is beneficial for promoting the regeneration of defective tissues. 33,[59][60][61] The physical and chemical properties and structural characteristics of ATP make it a potential material for bone tissue repair. 33 Our previous experiments confirmed that nanoattapulgite has good biocompatibility and promotes bone formation.…”

Targeted treatment for osteoarthritis: drugs and delivery system

“…Besides, this hydrogel conjugate has an optimizable release rate regulated by physiological microenvironment. Recently, inartificial clay mineral attapulgite (ATP) was used to produce an enhanced supramolecular hydrogel by cyclodextrin pseudopolyrotaxane (PPR) system (Ha et al., 2021 ). This ATP hybrid hydrogel appears to sustained release of Dcf, good biocompatibility and remarkable anti-inflammatory in vivo test.…”