Engineering quantum optical responses of microtubules through tryptophan-network simulations and ultraviolet spectroscopy
Abstract
Microtubules host dense ultraviolet-absorbing aromatic networks, suggesting an opportunity to engineer their optical response for biotechnology. Here we assess the feasibility of tuning microtubule fluorescence by combining an excitonic radiative-coupling model with molecular-dynamics-derived microtubule-like assemblies and steady-state absorbance and fluorescence measurements in microplate geometries. Simulations quantify how positional and orientational fluctuations reshape radiative rates and quantum yield, and predict how perturbing the tryptophan network by removing a specific site, adding an extra tryptophan at candidate binding pockets, or using mixed modification fractions can modulate emission. Experiments on porcine tubulin dimers and taxol-stabilized microtubules support these trends: polymerization enhances microtubule quantum yield at 280 nm and yields bounded changes at 295 nm due to scattering, while added L-tryptophan reproducibly quenches microtubules at both wavelengths. Together, theory and experiment provide evidence for chemically addressable tuning of microtubule quantum yield and motivate design rules for engineered microtubule photonics.
Keywords
Cite
@article{arxiv.2604.18604,
title = {Engineering quantum optical responses of microtubules through tryptophan-network simulations and ultraviolet spectroscopy},
author = {Lea Gassab and Travis J. A. Craddock},
journal= {arXiv preprint arXiv:2604.18604},
year = {2026}
}