Ghosh Amar, Panneerselvam Murugesan, Mondal Sourav, Das Prasanta, Singha Tukai, Rana Subhasis, Costa Luciano T, Satpati Biswarup, Das Suman, Sur Ujjal Kumar, Senapati Dulal
Biophysical Chemistry Laboratory, Physical Chemistry Section, Department of Chemistry, Jadavpur University, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India.
MolMod-CS-Instituto de Química, Universidade Federal Fluminense, Campos Valonginho s/n, Centro, Niterói, 24020-14 Rio de Janeiro, Brazil.
ACS Omega. 2024 Sep 24;9(40):41504-41520. doi: 10.1021/acsomega.4c05118. eCollection 2024 Oct 8.
Selective use of ingredients out of a specific natural product (e.g., fruit, leaf, flower, or honey extract) or their mixture (e.g., bacteria, viruses, fungi, plants, etc.) by smart manipulation of precursors and reaction conditions to synthesize nanoparticles can provide us a low-cost, environmentally friendly route for their industrial-scale production. The presence of more than one active ligand (sourced natural product extract) on the surface not only makes them the most stable (electrostatically) and monodispersed (controlled kinetics) but also devoid of any external ligand-assisted aggregation. This empowered us to modify the surface of the nanoparticles in a monolayered fashion or to couple between nanoparticles through a ligand-assisted chemical coupling pathway to avoid their aggregation and hence to keep their nanoscale property intact. A metal-to-ligand charge transfer (MLCT) trajectory combined with electromagnetic field-induced coherent capacitive coupling between two nanoparticles was introduced to explain the gigantic Raman enhancement observed from these nanoparticles. As a model system, we have synthesized the nanoparticles from rose extract as the active ligand ingredient source for 2-phenyl ethanol, linalool, citronellol, nerol, geraniol, pyrogallol (CH(OH)), and quercetin (3,3',4',5,7-pentahydroxyflavone) and the surface of the synthesized nanoparticles has been modified by 4-mercaptobenzoic acid (4-MBA) acting as a Raman tag. The obtained structural and spectroscopic data correlate well between our numerical and density functional theory (DFT)-based calculations to justify their gigantic SERS activity, which may lead us to propose an unexplored coherent capacitive coupling-based Raman enhancement mechanism.
通过巧妙控制前驱体和反应条件，从特定天然产物（如水果、叶子、花朵或蜂蜜提取物）或其混合物（如细菌、病毒、真菌、植物等）中选择性地使用成分来合成纳米颗粒，可为其工业规模生产提供一条低成本、环境友好的途径。表面存在一种以上活性配体（源自天然产物提取物）不仅使它们在静电方面最稳定且单分散（动力学可控），而且不存在任何外部配体辅助聚集。这使我们能够以单层方式修饰纳米颗粒的表面，或通过配体辅助化学偶联途径在纳米颗粒之间进行偶联，以避免它们聚集，从而保持其纳米级特性不变。引入了金属 - 配体电荷转移（MLCT）轨迹以及两个纳米颗粒之间电磁场诱导的相干电容耦合，以解释从这些纳米颗粒中观察到的巨大拉曼增强效应。作为一个模型系统，我们从玫瑰提取物中合成了纳米颗粒，玫瑰提取物作为2 - 苯基乙醇、芳樟醇、香茅醇、橙花醇、香叶醇、连苯三酚（CH(OH)）和槲皮素（3,3',4',5,7 - 五羟基黄酮）的活性配体成分来源，并且合成的纳米颗粒表面已用作为拉曼标签的4 - 巯基苯甲酸（4 - MBA）进行了修饰。所获得的结构和光谱数据在我们基于数值和密度泛函理论（DFT）的计算之间具有良好的相关性，以证明其巨大的表面增强拉曼散射（SERS）活性，这可能使我们提出一种未被探索的基于相干电容耦合的拉曼增强机制。
