Department of Otolaryngology/Head and Neck Surgery, VU University Medical Center, Amsterdam, The Netherlands.
Eur J Nucl Med Mol Imaging. 2012 Jul;39(7):1161-8. doi: 10.1007/s00259-012-2080-5. Epub 2012 Feb 17.
At present, the only approved fluorescent tracer for clinical near-infrared fluorescence-guided sentinel node (SN) detection is indocyanine green (ICG), but the use of this tracer is limited due to its poor retention in the SN resulting in the detection of higher tier nodes. We describe the development and characterization of a next-generation fluorescent tracer, nanocolloidal albumin-IRDye 800CW that has optimal properties for clinical SN detection.
The fluorescent dye IRDye 800CW was covalently coupled to colloidal human serum albumin (HSA) particles present in the labelling kit Nanocoll in a manner compliant with current Good Manufacturing Practice. Characterization of nanocolloidal albumin-IRDye 800CW included determination of conjugation efficiency, purity, stability and particle size. Quantum yield was determined in serum and compared to that of ICG. For in vivo evaluation a lymphogenic metastatic tumour model in rabbits was used. Fluorescence imaging was performed directly after peritumoral injection of nanocolloidal albumin-IRDye 800CW or the reference ICG/HSA (i.e. ICG mixed with HSA), and was repeated after 24 h, after which fluorescent lymph nodes were excised.
Conjugation of IRDye 800CW to nanocolloidal albumin was always about 50% efficient and resulted in a stable and pure product without affecting the particle size of the nanocolloidal albumin. The quantum yield of nanocolloidal albumin-IRDye 800CW was similar to that of ICG. In vivo evaluation revealed noninvasive detection of the SN within 5 min of injection of either nanocolloidal albumin-IRDye 800CW or ICG/HSA. No decrease in the fluorescence signal from SN was observed 24 h after injection of the nanocolloidal albumin-IRDye 800CW, while a strong decrease or complete disappearance of the fluorescence signal was seen 24 h after injection of ICG/HSA. Fluorescence-guided SN biopsy was very easy.
Nanocolloidal albumin-IRDye 800CW is a promising fluorescent tracer with optimal kinetic features for SN detection.
目前，唯一获得批准用于临床近红外荧光引导前哨淋巴结（SN）检测的荧光示踪剂是吲哚菁绿（ICG），但由于其在 SN 中的保留不佳，导致检测到更高层次的节点，因此该示踪剂的使用受到限制。我们描述了一种下一代荧光示踪剂的开发和特性，即纳米胶体白蛋白-IR-Dye 800CW，它具有用于临床 SN 检测的最佳特性。
荧光染料 IR-Dye 800CW 通过与现行良好生产规范相符的方式与标记试剂盒 Nanocoll 中存在的胶体人血清白蛋白（HSA）颗粒共价偶联。纳米胶体白蛋白-IR-Dye 800CW 的特性包括测定结合效率、纯度、稳定性和粒径。量子产率在血清中进行测定，并与 ICG 进行比较。体内评估使用兔淋巴生成转移性肿瘤模型。在肿瘤周围注射纳米胶体白蛋白-IR-Dye 800CW 或参考 ICG/HSA（即 ICG 与 HSA 混合）后直接进行荧光成像，并在 24 小时后重复，之后切除荧光性淋巴结。
IRDye 800CW 与纳米胶体白蛋白的偶联效率始终约为 50%，并且得到了稳定且纯净的产物，而不会影响纳米胶体白蛋白的粒径。纳米胶体白蛋白-IR-Dye 800CW 的量子产率与 ICG 相似。体内评估表明，在注射纳米胶体白蛋白-IR-Dye 800CW 或 ICG/HSA 后 5 分钟内可无创检测 SN。在注射纳米胶体白蛋白-IR-Dye 800CW 24 小时后，SN 的荧光信号无明显下降，而注射 ICG/HSA 24 小时后，荧光信号明显下降或完全消失。荧光引导 SN 活检非常容易。
纳米胶体白蛋白-IR-Dye 800CW 是一种很有前途的荧光示踪剂，具有用于 SN 检测的最佳动力学特征。
