PDF(Pubmed)
Abstract：
The degradation of collagen in different body parts is a critical point for designing collagen-based biomedical products. Here, three kinds of collagens labeled by second near-infrared (NIR-II) quantum dots (QDs), including collagen with low crosslinking degree (LC), middle crosslinking degree (MC) and high crosslinking degree (HC), were injected into the subcutaneous tissue, muscle and joints of the mouse model, respectively, in order to investigate the in vivo degradation pattern of collagen by NIR-II live imaging. The results of NIR-II imaging indicated that all tested collagens could be fully degraded after 35 days in the subcutaneous tissue, muscle and joints of the mouse model. However, the average degradation rate of subcutaneous tissue (k = 0.13) and muscle (k = 0.23) was slower than that of the joints (shoulder: k = 0.42, knee: k = 0.55). Specifically, the degradation rate of HC (k = 0.13) was slower than LC (k = 0.30) in muscle, while HC showed the fastest degradation rate in the shoulder and knee joints. In summary, NIR-II imaging could precisely identify the in vivo degradation rate of collagen. Moreover, the degradation rate of collagen was more closely related to the implanted body parts rather than the crosslinking degree of collagen, which was slower in the subcutaneous tissue and muscle compared to the joints in the mouse model.
摘要：
胶原蛋白在不同身体部位的降解是设计基于胶原蛋白的生物医学产品的关键点。这里,三种胶原被第二近红外(NIR-II)量子点(QDs)标记,包括低交联度（LC）的胶原蛋白，中交联度（MC）和高交联度（HC），被注射到皮下组织中，小鼠模型的肌肉和关节，分别,为了通过NIR-II实时成像研究胶原蛋白的体内降解模式。NIR-II成像结果表明，所有测试的胶原蛋白在皮下组织中35天后可以完全降解，小鼠模型的肌肉和关节。然而,皮下组织(k=0.13)和肌肉(k=0.23)的平均降解速度慢于关节(肩:k=0.42,膝:k=0.55)。具体来说,肌肉中HC(k=0.13)的降解速率慢于LC(k=0.30),HC在肩关节和膝关节的降解速度最快。总之,NIR-II成像可以准确识别胶原的体内降解速率。此外，胶原的降解速率与植入的身体部位有关,而不是与胶原的交联程度有关,与小鼠模型中的关节相比，皮下组织和肌肉的速度较慢。
