Multifunctioning of carboxylic-cellulose nanocrystals on the reinforcement of compressive strength and conductivity for acrylic-based hydrogel.

Simultaneously having competitive compressive properties, fatigue-resistant stability, excellent conductivity and sensitivity has still remained a challenge for acrylic-based conductive hydrogels, which is critical in their use in the sensor areas where pressure is performed. In this work, an integrated strategy was proposed for preparing a conductive hydrogel based on acrylic acid (AA) and sodium alginate (SA) by addition of carboxylic-cellulose nanocrystals (CNC-COOH) followed by metal ion interaction to reinforce its compressive strength and conductivity simultaneously. The CNC-COOH played a multifunctional role in the hydrogel by well-dispersing SA and AA in the hydrogel precursor solution for forming a uniform semi-interpenetrating network, providing more hydrogen bonds with SA and AA, more -COOH for metal ion interactions to form uniform multi-network, and also offering high modulus to the final hydrogel. Accordingly, the as-prepared hydrogels showed simultaneous excellent compressive strength (up to 3.02 MPa at a strain of 70 %) and electrical conductivity (6.25 S m-1), good compressive fatigue-resistant (93.2 % strength retention after 1000 compressive cycles under 50 % strain) and high sensitivity (gauge factor up to 14.75). The hydrogel strain sensor designed in this work is capable of detecting human body movement of pressing, stretching and bending with highly sensitive conductive signals, which endows it great potential for multi-scenario strain sensing applications.

Cepharanthine ameliorates titanium particle-induced osteolysis by inhibiting osteoclastogenesis and modulating OPG/RANKL ratio in a murine model.

Periprosthetic asepteic loosening, caused by wear debris, is one of the most severe complications, generally resulting in implant failure. Extensive osteoclast formation and activation are considered as the cause for periprosthetic osteolysis. However, few approaches have been approved to be used for preventing early-stage periprosthetic osteolysis. In this study, we investigated the preventive effects of CEP on titanium particles-induced osteolysis in a murine calvaria model. This inhibitory effect was confirmed to be realized by attenuating osteoclastogenesis in vivo. In addition, CEP markedly reduced wear particles-induced elevation of receptor activator of nuclear factor kappa B ligand (RANKL)/Osteoprotegerin (OPG) ratio in vivo. In conclusion, these data concluded that CEP demonstrated a preventive effect of CEP on titanium particles induced osteolysis, suggesting that CEP might be a novel therapeutic for periprosthesis loosening.