Circular dichroism (CD) is a standard method for the analysis of biomolecular conformation. It is very reliable when applied to molecules, but requires relatively large amounts of solution. Plasmonics offer the perspective of enhancement of CD signals, which would extend CD spectrometry to smaller amounts of molecules and to weaker chiral signals. However, plasmonic enhancement comes at the cost of additional complications: averaging over all orientations is no longer possible or reliable, linear dichroism leaks into CD signals because of experimental imperfections, scattering and its interference with the incident beam must be taken into account, and the interaction between chiral molecules and possibly chiral plasmonic structures considerably complicates the interpretation of measured signals. This Perspective aims to explore the motivations and problems of plasmonic chirality and to re-evaluate present and future solutions.

中文翻译：

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光学探测单等离子体纳米结构和单分子的手性：潜力和障碍

圆二色性 (CD) 是分析生物分子构象的标准方法。应用于分子时非常可靠，但需要相对大量的溶液。等离激元学提供了增强 CD 信号的前景，这会将 CD 光谱法扩展到更少量的分子和更弱的手性信号。然而，等离子增强是以额外的复杂性为代价的：对所有方向的平均不再可能或可靠，线性二色性由于实验缺陷而泄漏到 CD 信号中，必须考虑散射及其对入射光束的干扰，并且手性分子和可能的手性等离子体结构之间的相互作用使测量信号的解释变得相当复杂。