Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry, Wuhan University, Wuhan 430072, China.
Carbohydr Polym. 2022 Oct 1;293:119739. doi: 10.1016/j.carbpol.2022.119739. Epub 2022 Jun 17.
The reversible thermosensitive hydroxypropyl chitin (HPCH) has been widely investigated for drug delivery, tissue engineering, wound repair and antibacterial hemostasis. To achieve non-invasive and real-time visualization of in vivo degradation of HPCH, aggregation-induced emission fluorogen (AIEgen) was introduced covalently in HPCH in water to obtain thermosensitive fluorescent hydroxypropyl chitin (FHPCH) avoiding using any organic solvent. The obtained fluorescent FHPCH hydrogel showed strong yellow-green fluorescence feature under UV irradiation, enabling visualization of the hydrogel with reversible thermosensitivity and reliable injectability. The in vitro enzymatic degradation study of FHPCH hydrogel showed that the attenuation of fluorescence intensity well matched with hydrogel weight loss. The injection through a 26-gauge needle for real-time fluorescence imaging in mice indeed indicated that AIE modified injectable thermosensitive FHPCH can be used for non-invasive, continuous and real-time visualization and quantitative analysis of in vivo degradation. This provides a new method for non-invasive real-time monitoring of similar implantable materials.
具有温敏性的羟丙基壳聚糖（HPCH）已被广泛研究用于药物传递、组织工程、伤口修复和抗菌止血。为了实现 HPCH 在体内降解的非侵入性和实时可视化，通过将聚集诱导发射荧光团（AIEgen）共价引入 HPCH 中，在水中获得温敏荧光羟丙基壳聚糖（FHPCH），避免使用任何有机溶剂。所得到的荧光 FHPCH 水凝胶在紫外光照射下显示出强烈的黄绿色荧光特征，能够可视化具有可逆温敏性和可靠可注射性的水凝胶。FHPCH 水凝胶的体外酶降解研究表明，荧光强度的衰减与水凝胶的失重很好地匹配。通过 26 号针头注射用于在小鼠体内进行实时荧光成像，确实表明 AIE 修饰的可注射温敏 FHPCH 可用于非侵入性、连续和实时可视化以及体内降解的定量分析。这为类似可植入材料的非侵入性实时监测提供了一种新方法。
