From Nucleobases to DNA: Clustering-Triggered Emission and Pressure-Induced Emission Enhancement

TL;DR

This study reveals that DNA exhibits unique luminescent behaviors, including clustering-triggered emission and pressure-enhanced luminescence, driven by its structural hierarchy and intermolecular interactions, expanding understanding beyond traditional fluorescence models.

Contribution

It introduces the clustering-triggered emission mechanism for DNA and demonstrates pressure-induced luminescence enhancement, providing new insights into DNA photophysics and potential luminescent material development.

Findings

DNA shows excitation-dependent emission in aggregates

Room-temperature phosphorescence observed in solid DNA

Pressure significantly enhances DNA luminescence by intermolecular interactions

Abstract

The photophysical properties of deoxyribonucleic acid (DNA) are fundamental to life sciences and biophotonics. While previous studies have generally been restricted to fluorescence, attributing it to pi-pi* transitions and charge transfer within nucleobases in dilute solution, these understandings fail to explain the pronounced visible emission in physiological and aggregated states, and moreover, ignore the possible phosphorescence. Addressing this critical gap, we systematically investigate native DNA across its structural hierarchy, from nucleobases to single-stranded chains, under varying states. We demonstrate that DNA exhibits excitation-dependent emission in aggregates and moreover room-temperature phosphorescence (RTP) in the solid state. These behaviors are rationalized by the clustering-triggered emission (CTE) mechanism, where nucleobases and electron-rich nonaromatic moieties like sugar and phosphate synergistically contribute to DNA photophysics. High-pressure experiments reveal a 207-fold luminescence enhancement for nucleotides at 26 GPa, largely retained after decompression, underscoring the precise control of emission by intermolecular interactions. This study not only elucidates the intrinsic luminescence mechanism of DNA and but also establishes pressure modulation as a versatile approach for developing new nucleic acid-inspired luminescent materials.