文献：Oral nanotherapeutics with enhanced mucus penetration and ROS-responsive 2 drug release capacities for delivery of curcumin to colitis tissues

文献链接：https://pubs.rsc.org/en/content/articlelanding/2021/tb/d0tb02092c

作者：Yamei Huang, Brandon S.B. Canup, Shuangquan Gou,Nanxi Chen, Fangyin Dai, Bo Xiao,and Changming Li

相关产品：Cy7

原文摘要：

The therapeutic efficacies of oral nanotherapeutics for ulcerative colitis (UC) are seriously hindered by the lack of mucus-penetrating capacity and uncontrolled drug release. To overcome these limitations, the surface of poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles (NPs) was functionalized with pluronic F127 (PF127), and catalase (CAT)/curcumin (CUR) were co-encapsulated into these NPs. The obtained P-CUR/CAT-NPs had a hydrodynamic particle size of approximately 274.1 nm, narrow size distribution, negative zeta potential (-14.0 mV), and smooth surface morphology. Moreover, the introduction of PF127 to the surface of NPs not only facilitated their mucus penetration, but also improved their cellular uptake efficiency by the target cells (macrophages). We further found that the encapsulation of CAT could remarkably increase the release rate of CUR from NPs in the presence of an H2O2-rich environment. Additionally, P-CUR/CAT-NPs showed the strongest capacity to suppress the secretion of the main pro-inflammatory cytokines, in comparison with their counterparts (CUR-NPs and P-CUR-NPs). Importantly, oral administration of P-CAT/CUR-NPs showed the best therapeutic outcomes than the other NPs. Collectively, these results clearly demonstrate that these mucus-penetrating NPs loading with CAT and CUR can be exploited as an efficien nanotherapeutic for UC therapy.

Cy7：Cy7 是一种花菁染料（Cyanine Dyes），它的化学结构是由多个共轭双键组成的聚甲炔链，这种结构赋予了它良好的光吸收和荧光发射特性。其分子结构相对较大且复杂，共轭体系使其能够在特定波长范围内吸收和发射光子。它具有较高的消光系数，这意味着它能够有效地吸收光。在近红外区域（750 - 770nm 为吸收峰）有很强的吸收能力，发射波长大约在 780 - 800nm，这使得它在生物样本检测中很有用，因为生物组织和细胞在这个波长范围内自身荧光较弱，减少了背景干扰。Cy7 染料的荧光量子产率相对较高，这表明它在吸收光子后，能够以较高的效率发射出荧光光子，有助于产生较强的荧光信号。基于Cy7的性能，介绍如下：

图：CY7结构式

Cy7标记P-CUR/CAT-NPs：

将 P - CUR/CAT - NPs 分散在 PBS 缓冲液中，浓度根据纳米粒子的量和实验需求调整。

向 P - CUR/CAT - NPs 分散液中缓慢加入适量的 Cy7 染料溶液，使 Cy7 与纳米粒子的摩尔比在一定区间之间。通过涡旋混合器充分混合，确保 Cy7 染料与纳米粒子充分接触。根据 Cy7 染料的性质和反应类型来控制反应温度和时间。对于 Cy7 - NHS 酯与纳米粒子上氨基的反应，通常在室温下反应。如果反应较慢，可以适当延长反应时间或提高反应温度，但要注意避免过高温度导致纳米粒子团聚或者 Cy7 染料的降解。

图：电镜图像

结论：

该文献成功制出P-CUR/CAT-NPs，Cy7成功标记了P-CUR/CAT-NPs。当将标记后的 P - CUR/CAT - NPs 注射到体内后，可以利用成像系统实时监测纳米粒子在体内各个器官和组织中的分布情况。结果表明，装载CAT和CUR的穿透黏液的NPs可以作为UC heal的有效纳米疗法。