Gelatin-based composite hydrogels with biomimetic lubrication and sustained drug release

Abstract

The occurrence of osteoarthritis is closely related to progressive and irreversible destruction of the articular cartilage, which increases the friction significantly and causes further inflammation of the joint. Thus, a scaffold for articular cartilage defects should be developed via lubrication restoration and drug intervention. In this study, we successfully synthesized gelatin-based composite hydrogels, namely GelMA-PAM-PMPC, with the properties of biomimetic lubrication and sustained drug release by photopolymerization of methacrylic anhydride modified gelatin (GelMA), acrylamide (AM), and 2-methacryloyloxyethyl phosphorylcholine (MPC). Tribological test showed that the composite hydrogels remarkably enhanced lubrication due to the hydration lubrication mechanism, where a tenacious hydration shell was formed around the zwitterionic phosphocholine headgroups. In addition, drug release test indicated that the composite hydrogels efficiently encapsulated an anti-inflammatory drug (diclofenac sodium) and achieved sustained release. Furthermore, the in vitro test revealed that the composite hydrogels were biocompatible, and the mRNA expression of both anabolic and catabolic genes of the articular cartilage was suitably regulated. This indicated that the composite hydrogels could effectively protect chondrocytes from inflammatory cytokine-induced degeneration. In summary, the composite hydrogels that provide biomimetic hydration lubrication and sustained local drug release represent a promising scaffold for cartilage defects in the treatment of osteoarthritis.

Zwitterionic Biomaterials

“…For example, MPC was copolymerized with gelatin methacrylate and acrylamide to fabricate a composite hydrogel as a scaffold for articular cartilage defects. 355 The lubrication property was found to be highly dependent on the MPC content. Under the test conditions of 0.5 N load and 2 Hz frequency, the addition of 30% MPC reduced the COF value from 0.052 to 0.011, while increasing the MPC content to 50% did not further improve the lubrication.…”

“…Zwitterionic moieties are introduced into various hydrogel systems to reduce their interfacial friction. For example, MPC was copolymerized with gelatin methacrylate and acrylamide to fabricate a composite hydrogel as a scaffold for articular cartilage defects . The lubrication property was found to be highly dependent on the MPC content.…”

Recent Advances in Zwitterionic Hydrogels: Preparation, Property, and Biomedical Application

“…Zwitterionic materials are a class of materials that contain both cationic and anionic groups, with no overall charge (neutral). Zwitterionic materials can be divided into the following categories according to the monomer structural characteristics (as shown in Figure 3 a): (1) phosphobetaine with a phosphate group and a terminal quaternary ammonium group [ 21 , 22 , 23 , 24 ]; (2) sulfobetaine or carboxybetaine with a quaternary ammonium group and a terminal carboxyl or sulfonic group [ 25 , 26 , 27 , 28 ]; (3) zwitterionic polyampholytes [ 29 ]. For the first two kinds of materials, each side-chain unit in the polymer contains an equal amount of positive and negative charges, which is electrically neutral.…”

Elaborate design of shell component for manipulating the sustained release behavior from core–shell nanofibres

“…The functionality of materials always depends on their physicochemical properties [ 6 – 8 ]. Thus, these functional materials can be divided into electrochemical sensing materials [ 9 ], photosensitive materials [ 10 ], hydrophilic materials [ 11 ], antibacterial materials [ 12 – 14 ], and sustained-release drug materials [ 15 – 17 ]. The combination of different materials can theoretically improve functionality.…”