Enhancement of deep ultraviolet chiral molecular sensing performance by collective lattice resonances of diamond nanostructure arrays

Q: Why is detecting circular dichroism (CD) in the deep ultraviolet (DUV) region important?

DUV CD spectroscopy can reflect both enantiomer concentration and molecular structural information, enabling resolution of molecular secondary structure and solution purity.

Q: What limits the sensitivity of conventional DUV chiral detection?

The intrinsic chiroptical signals are extremely weak, DUV optical systems have lower transmittance, and photodetectors respond with reduced sensitivity, which collectively lower the signal-to-noise ratio.

Q: How does the proposed diamond nanostructure array enhance optical chirality and CD signals?

The design excites collective lattice resonance modes with non-local field distributions and couples electric and magnetic CLRs, increasing optical chirality enhancement in the gap region and yielding much stronger DUV CD signals with concentration-dependent linearity.

Sep 29, 2026

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Detecting circular dichroism (CD) spectra of chiral molecules in the deep ultraviolet (DUV) region enables enantiomer concentration measurement and reveals molecular structural information. Conventional approaches suffer from weak intrinsic chiroptical signals and poor field localization, limiting sensitivity at low concentrations. A diamond nanostructure array is engineered to excite collective lattice resonance (CLR) modes and introduce electric–magnetic CLR coupling, producing strong optical chirality enhancement in the inter-array gaps. Simulations show a 22-fold enhancement in DUV CD signals with linear dependence on molecular concentration, supporting ultrasensitive detection of chiral biomolecules.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages11

Reading Time28 min

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Introduction

Chirality and circular dichroism in the deep ultraviolet region

Challenges in DUV chiral detection and need for signal enhancement

Nanophotonic strategy using superchiral near-fields and CLR modes

Nanoscale Advances PAPER Cite this: DOI: 10 .1039/d5na00768b Received 11th August 2025 Accepted 10th November 2025 DOI: 10.1039/d5na00768b[rsc.li/nanoscale-advances](rsc.li/nanoscale-advances) Enhancement of deep ultraviolet chiral molecular sensing performance by collective lattice resonances of diamond nanostructure arrays Shengsui Cai,† Jing Wang,†* Wenxuan Liu, Zhaolong Cao, Huanjun Chen, Lei Shao * and Shaozhi Deng Detecting the circular dichroism (CD) spectra of chiral molecules in the deep ultraviolet (DUV) region is of signiﬁcant research importance in the biomedical ﬁeld, as it can reﬂect not only enantiomer concentration but also molecular structural information. Although low-loss dielectric materials in the ultraviolet region can avoid the photothermal eﬀects of traditional plasmonic materials, their poor electromagnetic ﬁeld localization limits their application in molecular signal enhancement. Here, we designed a diamond nanostructure array. By exciting the collective lattice resonance (CLR) modes with non-local ﬁeld distribution characteristics and introducing the coupling between the electric and magnetic CLRs, the optical chirality enhancement in the gap region between the diamond nanostructures is increased toa maximum of more than 150, with an average of over 52 at DUV wavelengths. Such characteristics allow the largely enhanced spatial superposition between the superchiral near ﬁeld and the target chiral analytes. Moreover, simulation results demonstrate a 22-fold enhancement in the DUV CD signals of chiral molecules, with the enhanced CD intensity exhibiting a linear dependence on molecular concentration. Our results could be potentially used for ultrasensitive detection of chiral biomolecules, which is of interest in biopharmaceutical research applications such as rapid detection of chiral drug molecules at ultra-low concentrations. Introduction Chirality describes the geometric properties where an object cannot be superimposed onto its mirror image by rotation or translation. This concept is pivotal across numerous scienti􀀁c disciplines and holds vital importance in biology and chemistry: the fundamental biomolecules of life (such as L-amino acids and right-handed DNA) are predominantly chiral. Taking proteins as an example, the precise folding of their tertiary structures strictly depends on sequences composed of Lcon􀀁gured amino acids. This perpetuation of chirality underpins the functionality of biomolecules. Consequently, the enantiomer-speci􀀁c interaction between chiral pharmaceuticals and biomolecules can elicit profoundly diﬀerent biological eﬀects. A classic case is thalidomide—the (R)-enantiomer alleviates morning sickness, while the metabolites of the (S) -enantiomer cause severe fetal deformities.1 The properties of chiral compounds are dictated by their stereochemistry, making the distinction between enantiomers State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Provincial Key Laboratory of Display Materials and Technologies, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510275, China. E-mail: [shaolei5@mail.sysu.edu.cn](shaolei5@mail.sysu.edu.cn); [wangj968@mail.sysu.edu.cn](wangj968@mail.sysu.edu.cn) † These authors contributed equally to this work. © 2025 The Author(s) . Published by the Royal Society of Chemistry indispensable in both research and application. Among existing detection techniques, CD spectroscopy characterizes chirality by measuring the diﬀerential absorption of le􀀁-handed (LCP) and right-handed (RCP) circularly polarized light.2 Most organic molecules absorb light in the ultraviolet (UV) region due to their electronic transitions, and the absorption bands correspond to speci􀀁c functional groups. Therefore, CD spectroscopy in the deep-ultraviolet (DUV) region with the wavelength l < 300 nm can simultaneously resolve molecular secondary structure3 and solution purity,4 oﬀering in

FAQs

Why is detecting circular dichroism (CD) in the deep ultraviolet (DUV) region important?

DUV CD spectroscopy can reflect both enantiomer concentration and molecular structural information, enabling resolution of molecular secondary structure and solution purity.

What limits the sensitivity of conventional DUV chiral detection?

The intrinsic chiroptical signals are extremely weak, DUV optical systems have lower transmittance, and photodetectors respond with reduced sensitivity, which collectively lower the signal-to-noise ratio.

How does the proposed diamond nanostructure array enhance optical chirality and CD signals?

The design excites collective lattice resonance modes with non-local field distributions and couples electric and magnetic CLRs, increasing optical chirality enhancement in the gap region and yielding much stronger DUV CD signals with concentration-dependent linearity.

Sep 29, 2026

Upload by Himbo