Zhang Yumiao, Jeon Mansik, Rich Laurie J, Hong Hao, Geng Jumin, Zhang Yin, Shi Sixiang, Barnhart Todd E, Alexandridis Paschalis, Huizinga Jan D, Seshadri Mukund, Cai Weibo, Kim Chulhong, Lovell Jonathan F
1] Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, New York 14260, USA [2] Chemical and Biological Engineering, University at Buffalo, State University of New York, Buffalo, New York 14260, USA.
1] Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, New York 14260, USA [2] Department of Creative IT Engineering, POSTECH, Pohang, Korea.
Nat Nanotechnol. 2014 Aug;9(8):631-8. doi: 10.1038/nnano.2014.130. Epub 2014 Jul 6.
There is a need for safer and improved methods for non-invasive imaging of the gastrointestinal tract. Modalities based on X-ray radiation, magnetic resonance and ultrasound suffer from limitations with respect to safety, accessibility or lack of adequate contrast. Functional intestinal imaging of dynamic gut processes has not been practical using existing approaches. Here, we report the development of a family of nanoparticles that can withstand the harsh conditions of the stomach and intestine, avoid systemic absorption, and provide good optical contrast for photoacoustic imaging. The hydrophobicity of naphthalocyanine dyes was exploited to generate purified ∼ 20 nm frozen micelles, which we call nanonaps, with tunable and large near-infrared absorption values (>1,000). Unlike conventional chromophores, nanonaps exhibit non-shifting spectra at ultrahigh optical densities and, following oral administration in mice, passed safely through the gastrointestinal tract. Non-invasive, non-ionizing photoacoustic techniques were used to visualize nanonap intestinal distribution with low background and remarkable resolution, and enabled real-time intestinal functional imaging with ultrasound co-registration. Positron emission tomography following seamless nanonap radiolabelling allowed complementary whole-body imaging.
需要更安全、更先进的方法来对胃肠道进行非侵入性成像。基于X射线辐射、磁共振和超声的成像方式在安全性、可及性或缺乏足够对比度方面存在局限性。使用现有方法对肠道动态过程进行功能性成像并不实际。在此，我们报告了一类纳米颗粒的研发情况，这类纳米颗粒能够耐受胃和肠道的恶劣环境，避免全身吸收，并为光声成像提供良好的光学对比度。利用萘酞菁染料的疏水性生成了纯化的约20纳米冷冻胶束，我们将其称为纳米萘，其具有可调谐且较大的近红外吸收值（>1000）。与传统发色团不同，纳米萘在超高光密度下光谱不发生偏移，并且在小鼠口服给药后能安全通过胃肠道。采用非侵入性、非电离光声技术以低背景和高分辨率可视化纳米萘在肠道的分布，并通过超声配准实现实时肠道功能成像。对纳米萘进行无缝放射性标记后的正电子发射断层扫描可实现互补性全身成像。
