Distance-Dependence of Photo-CIDNP in Biomimetic Tryptophan-Flavin Diads

07 May 2025, Version 1

Abstract

Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) are essential tools in natural and life sciences, but their low sensitivity often hampers their applicability. Photochemically induced dynamic nuclear polarization (photo-CIDNP) offers a versatile and mild method to overcome this limitation. Here, we report on structure-photo-CIDNP relationship studies in liquid-state NMR utilizing a holistic approach. We synthesized biomimetic tryptophan-flavin diads with varying linker lengths composed of conformationally rigid oligoproline units. The predominant polyproline II (PPII) helical structure ensures consistent donor-acceptor distances. Photo-CIDNP experiments revealed significant hyperpolarization effects, particularly in diads with six proline units, mimicking the spatial arrangement found in natural photoactive proteins. Our findings highlight the potential of these biomimetic diads to enhance nuclear hyperpolarization in NMR spectroscopy. This work provides valuable insights into the design of diads for efficient photo-CIDNP generation, paving the way for advanced studies in modern NMR and bio-MRI.

Keywords

photo-CIDNP
hyperpolarization
biomimetic diads
oligoprolines
spin correlated radical pairs

Supplementary materials

Title
Description
Actions
Title
Supporting Information
Description
General Procedures, Spectral and Computational Data, Compound Characterization
Actions
Title
Video 1
Description
MD simulation
Actions
Title
Video 2
Description
diad 2a
Actions
Title
Video 4
Description
diad 2c
Actions
Title
Video 4
Description
diad 3c
Actions
Title
Video 3d
Description
diad 3d
Actions
Title
parameters diads
Description
parameters diads for simulation
Actions
Title
PSF
Description
diad 3a
Actions
Title
PDB
Description
diad 3a
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.