Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, PR China.
Department of Obstetrics and Gynecology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, PR China.
J Colloid Interface Sci. 2018 Jan 1;509:515-521. doi: 10.1016/j.jcis.2017.09.007. Epub 2017 Sep 6.
Carbon nanodots (CDs) have been exhibiting increasing applications owing to their luminescence properties and biocompatibility as imaging probes in diagnosis. However, poor tumor targeting and penetration of CDs is still the biggest challenge limiting their tumor imaging efficacy. To improve the tumor targeting and penetration efficiency of CDs, we developed an active tumor targeting imaging system by simply fabricating a tumor-homing penetration peptide iRGD (CRGDKGPDC) to red shift emissive CDs (iRGD-CDs) with a physical method. Particularly, iRGD-CDs showed a small size and red shift fluorescence signals as CDs, which made iRGD-CDs suitable for in vivo fluorescence imaging. iRGD-CDs showed higher cellular uptake in vitro, while presented higher penetration and accumulation in tumor tissue in vivo, leading to better tumor imaging efficacy. In conclusion, decoration with iRGD could significantly increase the permeability of CDs in tumor vessels and tumor tissue, generating more CDs leaking out from tumor vasculature, consequently improving the sensitivity of tumor imaging.
碳纳米点 (CDs) 由于其发光性能和作为诊断成像探针的生物相容性，在应用方面的表现日益突出。然而，CDs 较差的肿瘤靶向性和穿透性仍然是限制其肿瘤成像效果的最大挑战。为了提高 CDs 的肿瘤靶向性和穿透效率，我们通过简单的物理方法制备了肿瘤归巢穿透肽 iRGD (CRGDKGPDC) 来对发射性 CDs (iRGD-CDs) 进行红光移，从而构建了主动肿瘤靶向成像系统。特别地，iRGD-CDs 表现出与 CDs 一样的小尺寸和红光荧光信号，这使得 iRGD-CDs 适合用于体内荧光成像。iRGD-CDs 在体外表现出更高的细胞摄取率，而在体内肿瘤组织中表现出更高的穿透和积累，从而实现更好的肿瘤成像效果。总之，用 iRGD 修饰可以显著增加 CDs 在肿瘤血管和肿瘤组织中的通透性，使更多的 CDs 从肿瘤血管中漏出，从而提高肿瘤成像的灵敏度。
