Identification and analysis of an impurity inducing clinical adverse effect in anti-adhesion carboxymethyl chitosan products

Hemostatic effect and safety evaluation of the absorbable macroporous polysaccharides composite hemostatic material prepared by a green fabrication approach

Carboxymethyl chitosan is widely used in the medical field such as wound healing and other medical fields. We previously fabricated the absorbable macroporous polysaccharides composite hemostatics (AMPCs) mainly composed of carboxymethyl chitosan which possess excellent hemostatic effect. To further elucidate the impact of CMCTs on the hemostatic effect and biosafety of AMPCs, carboxymethyl chitosan with different properties were used to prepare AMPCs. By comparing the physical and chemical properties, AMPCs performed high water absorption ability, especially Group 1 (swelling ratio reached 5792%), which facilitated the rapid formation of blood clots. It was confirmed by blood clotting index (BCI) and blood coagulation tests in vitro that Group 1 showed a slightly higher coagulation capacity than groups 2 and 3, which may be due to the positive charge on the surface of the cations in the salts attaches to the negative charge on the surface of the red blood cells, an electrostatic neutralization reaction occurs. The biosafety was a preliminary evaluation by implanted AMPCs into the back of Sprague-Dawley rats and the tissue was harvested after feeding for 28 days. The AMPCs exhibited good biosafety for whole blood and major organs during the degradation in vivo: during the degradation of AMPCs, excluding changes in some serum indicators, no tissue necrosis or inflammatory cell infiltration was observed in these organs, either by gross observation or histological analysis. These findings demonstrate that expecting to develop a highly functional and safe hemostatic agent based on Group 1 for rapid hemostasis applications in emergencies.

Novel Carboxylated Chitosan-Based Triptolide Conjugate for the Treatment of Rheumatoid Arthritis

A new platform for triptolide (TP) delivery was prepared by conjugating TP to a carboxylmethyl chitosan (CMCS). Compared with the natural TP, the TP-conjugate (TP-CMCS) containing TP of ~5 wt% exhibited excellent aqueous solubility (>5 mg/mL). Results of in vitro experiments showed that TP-CMCS could relieve TP-induced inhibition on RAW264.7 cells and apoptosis, respectively. Compared with the TP group, TP-CMCS could effectively alleviate the toxicity injury of TP and decreased the mortality rate of the mice (p < 0.05). TP-CMCS did not cause much damage to the liver (AST and ALT) and kidney (BUN and CRE) (p < 0.05). After administration, the levels of IL-6, IL-1β, and TNF-α decreased, and the arthritis detumescence percentages increased significantly, and the bony erosion degree was distinctly decreased in the TP-CMCS groups and TP group. Our results suggested that TP-CMCS was a useful carrier for the treatment of RA, which enhanced aqueous solubility of free TP and reduced drug toxicity in vitro and in vivo.