摘要
Localized surface plasmon resonance(LSPR)effects in gold nanoparticles(AuNPs)significantly influence the excited states of nearby molecules,offering unique opportunities for enhancing molecular triplet states.Herein,we report the synthesis of DNA-templated gold nanostars(AuNF_A15)and gold nanospheres(AuNS_T15)via a seed-mediated growth method and their ability to enhance the triplet state of coralyne,a small molecule with promising applications in photodynamic therapy(PDT).DNA single strands(A15 or T15)were employed as templates to regulate the morphology of AuNPs,resulting in nanostars and nanospheres.The nanostars exhibited a superior LSPR effect due to their“lightning rod effect",significantly enhancing coralyne’s triplet signal by 15-fold compared to a 10-fold enhancement observed with nanospheres.This enhancement was confirmed via steady-state and nanosecond transient absorption spectroscopy.These findings demonstrate that DNA-assembled gold nanostars hold exceptional potential for enhancing molecular triplet states,particularly for PDT applications involving DNA-targeting small molecules.
金纳米粒子的局域表面等离子体共振效应对邻近分子的激发态具有显著影响,为分子三重态的增强提供了独特的机遇.本文利用种子介导生长法,合成了DNA模板化金纳米星(AuNF_A15)和金纳米球(AuNS_T15),并系统研究了二者对甲氧檗因三重态的增强能力.甲氧檗因作为一种在光动力疗法领域具有广阔应用前景的小分子化合物,其激发态性质的调控具有重要意义.研究中采用DNA单链(A15或T15)作为形貌调控模板,成功制备了具有不同形貌特征的纳米星和纳米球结构.实验结果表明,金纳米星由于其尖端的“避雷针效应”表现出卓越的局域表面等离子体共振性能,使甲氧檗因的三重态信号获得了15倍的显著增强;相比之下,金纳米球的增强倍数为10倍.上述增强效果通过稳态光谱和纳秒级瞬态吸收光谱技术得到了充分验证.研究结果充分证明了DNA组装金纳米星在分子三重态增强方面的卓越潜力,特别是在基于DNA靶向小分子的光动力疗法应用中展现出重要的学术价值和应用前景.
基金
supported by the National Natural Science Foundation of China(Nos.21933005,22473014,and 22273007)
the National Key R&D Program of China(No.2022YFA1505400).
