文献：Biocompatible Croconaine Aggregates with Strong 1.2-1.3 μm Absorption for NIR-IIa Photoacoustic Imaging in Vivo

文献链接：https://xueshu.baidu.com/usercenter/paper/show?paperid=11500mv0ey5u0r0006100gj01g760580&site=xueshu_se

作者：Huanhuan Liu, Xiangyu Wang, Yanfang Huang, Honghui Li, Chenyu Peng, Hongzhang Yang,

Jindian Li, Huawei Hong, Zhao Lei, Xiaofen Zhang and Zijing Li

相关产品：

DSPE-PEG2000 磷脂-聚乙二醇2000

DSPE-PEG2000-Cy5.5 磷脂-聚乙二醇2000-菁染料Cy5.5

原文摘要：Although photoacoustic imaging (PAI) in the second near infrared (NIR-II) region (1.0-1.7 μm) is admired for deeper penetration and higher contrast, few organic NIR-II absorbers are available as exogenous contrast agents in vivo. A1094 belongs to the very few ~1.1 μm absorbing croconaine dyes that have superior extinction coefficient and tend to form irregular aggregation. In this study, shape-controlled A1094@DSPE-PEG2000 micelles with J

aggregate core with remarkable 1.2-1.3 μm absorption are fabricated as biocompatible organic agents. Excellent capabilities in photothermal conversion, photostability and PAI are found in in vitro studies. In vivo PAI of inguinal lymph nodes, in situ glioma pre- and postresection all demonstrate high lymph/tumor-targeting efficiency. ~4.54 mm deep brain lesion is imaged at 1200 nm with minimized background and increased contrast compared to 970 nm. Overall, we achieve significant bathochromic shift of organic absorbers and expanded their PAI application to the long wavelength end of NIR-IIa region.

DSPE-PEG2000是一种由二硬脂酰磷脂酰乙醇胺（DSPE）、聚乙二醇 2000（PEG2000）组成的复合物。DSPE 具有良好的脂质双层结构，可与细胞膜相互作用；PEG2000 具有良好的生物相容性和水溶性，能增加复合物的稳定性和溶解性。该产品且具有稳定的化学性质，应用在生物医学领域，如细胞成像、化合物输送等方面。该文献研究制备了A1094@DSPE-PEG2000200胶束作为生物相容性有机剂。

图：通过自组装制备a1094j-聚集体纳米薄膜

制备A1094@DSPE-PEG2000。

为了获得用于体内成像的胶束尺寸，测试了A1094和DSPE-PEG2000的不同摩尔比（0：1~1：0）。描述了在摩尔比为1：1（A1094@DSPE-PEG2000）下的胶束的制备。将A1094溶于氯仿中，搅拌后加入DSPE-PEG2000或DSPE-PEG2000的质量梯度。经过超声处理的均匀溶液和氯仿溶剂蒸发后，剩余的固体被拍摄在烧瓶的底部。然后，将磷酸盐缓冲溶液（PBS）倒入烧瓶中，使薄膜逐渐溶解，然后用微尖端探针超声仪超声溶液4 min。

图：A1094: DSPE-PEG2000不同摩尔比下的A1094j-聚集体纳米薄膜的DLS

结论：该文献提出制备了一种基于小分子纳米组装的NIR-IIa吸收的PA造影剂，具有良好的生物相容性、深穿透性、高成像效率和准确定位能力的脂质体平台。有机NIR染料A1094的聚集体呈~100 nm红移，增强了吸光度峰。此外，DSPE-PEG2000参与制备的具有生物相容性的A1094@DSPE-PEG2000胶束在光热试验中获得了良好的光学稳定性，明显优于ICG。A1094@DSPE-PEG2000具有较长的体内循环半衰期。