Quantum Tunneling Enables High-Flux Transport in Ion Channels

TL;DR

This paper demonstrates that quantum tunneling significantly enhances ion transport in biological channels, explaining high conductance levels and introducing a quantum perspective to ion channel physics.

Contribution

It introduces a non-perturbative quantum transport model for ion channels, revealing quantum tunneling as essential for high flux and challenging classical theories.

Findings

Quantum tunneling bypasses classical energy barriers.

Quantitative agreement with experimental conductance data.

Predicts novel terahertz transport resonances.

Abstract

Classical molecular dynamics and electro-diffusion theories have achieved profound success in elucidating ion selectivity and gating mechanisms. However, reconciling strict selectivity with high flux permeation in Angstrom-scaled biological ion channels poses a universal challenge in nanoscale physics, as classical models consistently underestimate single-channel conductance. Using a non perturbative quantum transport framework, we calculate the ion permeation dynamics through the selectivity filter within a transfer matrix formalism. We demonstrate that quantum tunneling allows ions to bypass classical Arrhenius suppression, quantitatively recovering the experimental conductance of Na+ and K+ channels. Crucially, our findings reveal that the exploitation of quantum mechanics is a fundamental prerequisite for achieving macroscopic physiological efficiency. By reframing ion channels as mesoscopic quantum conductors, this work establishes a transformative paradigm in quantum biology and predicts distinct transport resonances in the terahertz regime.