金纳米形状优化光敏剂表面增强拉曼信号

Surface Enhancement of Raman Signal with Gold Nano Shape Optimization Photosensitizer

摘要: 磺化铝酞菁(AlPcs)是一种具有优异光敏性的光敏剂，广泛应用于癌症的检测与治疗。然而，铝酞菁在临床检测中仍面临重要挑战，主要体现在其需要特定波长的激发光源和一定的浓度范围。为解决这一问题，本研究通过引入金纳米粒子，利用金纳米等离子体效应增强拉曼信号，从而实现低浓度下的快速、灵敏检测。表面增强拉曼散射(SERS)技术是通过在金属表面产生的局部电磁场显著增强拉曼散射信号，极大地提升了检测灵敏度。然而，尚未明确哪种金纳米材料对铝酞菁的拉曼信号增强效果最佳，且增强效果的具体数值也未被充分研究。在本研究中，我们采用有限时域差分(FDTD)方法对四种不同形态的金纳米结构进行了模拟，系统评估了铝酞菁与这些金纳米粒子复合后的拉曼信号增强效果。结果表明，尽管所有金纳米结构均可增强铝酞菁的拉曼信号，金纳米六边形与铝酞菁复合物(GNPL@AlPcs)在SERS性能中展现出最高的增强效率。实验数据与模拟结果高度一致，为药物检测领域中合适金纳米材料的选择提供了有力指导。

Abstract: Aluminum sulfonated phthalocyanine (AlPcs) is a kind of photosensitizer with excellent photosensitivity, which is widely used in the detection and treatment of cancer. However, aluminum phthalocyanine still faces important challenges in clinical detection, mainly reflected in its need for a specific wavelength excitation light source and a certain concentration range. In order to solve this problem, this study introduces gold nanoparticles and uses plasma effect to enhance Raman signal, so as to achieve fast and sensitive detection at low concentration. Surface-enhanced Raman scattering (SERS) technology significantly enhances the Raman scattering signal through the local electromagnetic field generated on the metal surface, which greatly improves the detection sensitivity. However, it is not clear which gold nanomaterials have the best enhancement effect on the Raman signal of aluminum phthalocyanine, and the specific value of the enhancement effect has not been fully studied. In this study, we used the finite difference time domain (FDTD) method to simulate four different forms of gold nanostructures, and systematically evaluated the Raman signal enhancement effect of aluminum phthalocyanine composite with these gold nanoparticles. The results showed that although all gold nanostructures could enhance the Raman signal of aluminum phthalocyanine, the gold hexagonal nanosheets and aluminum phthalocyanine complex (GNPL@AlPcs) exhibited the highest enhancement efficiency in SERS. The experimental data are highly consistent with the simulation results, which provides a strong guide for the selection of suitable gold nanomaterials in the field of drug detection.