Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia 30332, United States.
Nano Lett. 2023 Oct 25;23(20):9257-9265. doi: 10.1021/acs.nanolett.3c02177. Epub 2023 Oct 5.
In plasmonic nanoconstructs (NCs), fine-tuning interparticle interactions at the subnanoscale offer enhanced electromagnetic and thermal responses in the near-infrared (NIR) wavelength range. Due to tunable electromagnetic and thermal characteristics, NCs can be excellent photoacoustic (PA) imaging contrast agents. However, engineering plasmonic NCs that maximize light absorption efficiency across multiple polarization directions, i.e., exhibiting blackbody absorption behavior, remains challenging. Herein, we present the synthesis, computational simulation, and characterization of hyper-branched gold nanoconstructs (HBGNCs) as a highly efficient PA contrast agent. HBGNCs exhibit remarkable optical properties, including strong NIR absorption, high absorption efficiency across various polarization angles, and superior photostability compared to conventional standard plasmonic NC-based contrast agents such as gold nanorods and gold nanostars. and experiments confirm the suitability of HBGNCs for cancer imaging, showcasing their potential as reliable PA contrast agents and addressing the need for enhanced imaging contrast and stability in bioimaging applications.
在等离子体纳米结构 (NC) 中，在亚纳米尺度上精细调整粒子间相互作用，可以在近红外 (NIR) 波长范围内提供增强的电磁和热响应。由于可调谐的电磁和热特性，NC 可以成为出色的光声 (PA) 成像对比剂。然而，工程化等离子体 NC，使其在多个偏振方向上最大化光吸收效率，即表现出黑体吸收行为，仍然具有挑战性。在这里，我们提出了超支化金纳米结构 (HBGNC) 的合成、计算模拟和表征，作为一种高效的 PA 对比剂。HBGNC 表现出显著的光学性质，包括强近红外吸收、在各种偏振角度下的高吸收效率以及与传统标准等离子体 NC 基对比剂（如金纳米棒和金纳米星）相比的优异光稳定性。实验证实了 HBGNC 适用于癌症成像，展示了它们作为可靠的 PA 对比剂的潜力，并满足了生物成像应用中增强成像对比度和稳定性的需求。
