Dipartimento di Chimica U. Schiff, Università di Firenze, INSTM and European Laboratory for Non-Linear Spectroscopy, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
Anal Bioanal Chem. 2011 Apr;400(2):361-7. doi: 10.1007/s00216-011-4732-x. Epub 2011 Feb 18.
We investigated the chemisorption of self-assembled monolayers of sulfur-functionalized 4-amino-7-nitrobenzofurazan on gold and silver nanoisland films (NIFs) by means of surface-enhanced fluorescence (SEF) and surface-enhanced Raman scattering (SERS). The ligand is a push-pull molecule, where an intramolecular charge transfer occurs between an electron-donor and an electron-acceptor group, thus exhibiting nonlinear optical properties that are related to both SERS and SEF effects. The presence of different heteroatoms in the molecule ensures the possibility of chemical interaction with both silver and gold substrates. The SERS spectra suggest that furazan is bound to silver via lone pairs of the nitrogen atoms, whereas the ligand is linked to gold via a sulfur atom. Silver NIFs provide more efficient enhancement of both fluorescence and Raman scattering in comparison with gold NIFs. The present SEF and SERS investigation could provide useful information for foreseeing changes in the nonlinear responses of this push-pull molecule.
我们通过表面增强荧光（SEF）和表面增强拉曼散射（SERS）研究了硫功能化 4-氨基-7-硝基苯并呋咱自组装单层在金和银纳米岛薄膜（NIF）上的化学吸附。配体是一个推拉分子，分子内电子给体和电子受体基团之间发生电荷转移，从而表现出与 SERS 和 SEF 效应都相关的非线性光学性质。分子中不同杂原子的存在确保了与银和金基底进行化学相互作用的可能性。SERS 光谱表明，呋咱通过氮原子的孤对与银结合，而配体通过硫原子与金结合。与金 NIF 相比，银 NIF 提供了更有效的荧光和拉曼散射增强。本 SEF 和 SERS 研究可为预测这种推拉分子的非线性响应变化提供有用信息。
