PDF(Pubmed)
Abstract：
Plasmonic materials can generate strong electromagnetic fields to boost the Raman scattering of surrounding molecules, known as surface-enhanced Raman scattering. However, these electromagnetic fields are heterogeneous, with only molecules located at the \'hotspots\', which account for ≈ 1% of the surface area, experiencing efficient enhancement. Herein, we propose patterned plasmonic trimers, consisting of a pair of plasmonic dimers at the bilateral sides and a trap particle positioned in between, to address this challenge. The trimer configuration selectively directs probe molecules to the central traps where \'hotspots\' are located through chemical affinity, ensuring a precise spatial overlap between the probes and the location of maximum field enhancement. We investigate the Raman enhancement of the Au@Al2O3-Au-Au@Al2O3 trimers, achieving a detection limit of 10-14 M of 4-methylbenzenethiol, 4-mercaptopyridine, and 4-aminothiophenol. Moreover, single-molecule SERS sensitivity is demonstrated by a bi-analyte method. Benefiting from this sensitivity, our approach is employed for the early detection of lung tumors using fresh tissues. Our findings suggest that this approach is sensitive to adenocarcinoma but not to squamous carcinoma or benign cases, offering insights into the differentiation between lung tumor subtypes.
摘要：
等离子体材料可以产生强大的电磁场来增强周围分子的拉曼散射，称为表面增强拉曼散射。然而,这些电磁场是异质的，只有分子位于“热点”，占表面积的≈1%，体验有效的增强。在这里，我们提出了图案化的等离子体三聚体，由两侧的一对等离子体二聚体和位于两者之间的陷阱粒子组成，来应对这一挑战。三聚体构型通过化学亲和力选择性地将探针分子引导到“热点”所在的中心陷阱，确保探头和最大场增强位置之间的精确空间重叠。我们研究了Au@Al2O3-Au-Au@Al2O3三聚体的拉曼增强，4-甲基苯硫酚的检测限达到10-14M，4-巯基吡啶,和4-氨基苯硫酚。此外，通过双分析方法证明了单分子SERS灵敏度。受益于这种敏感性，我们的方法用于使用新鲜组织早期检测肺肿瘤。我们的研究结果表明，这种方法对腺癌敏感，但对鳞癌或良性病例不敏感。提供对肺肿瘤亚型之间的区别的见解。
