Tunable and Recyclable Piezoelectric Biomaterials via Ion‐Directed Guanine‐Quadruplex Assembly

Abstract The self‐assembly of biomaterials into piezoelectric architecture offers a promising pathway toward sustainable and functional alternatives to conventional piezoelectric materials. Herein, guanine‐quadruplex (GQ) structures are introduced as a new class of self‐assembled biomolecular piezoelectric materials, formed via facile ion‐mediated assembly of amphiphilic guanine derivatives in the presence of alkali metal ions (Li⁺, Na⁺, and K⁺). Through a combination of molecular dynamics (MD) simulations and experimental validation, an ion‐specific piezoelectric mechanism is uncovered, wherein K⁺‐assembled GQs show the highest dipole distortion and piezoelectric output due to favorable ionic positioning within the GQ columnar channel. Notably, the system allows facile tuning of piezoelectric performance by simply varying the coordinating ion and demonstrates excellent recyclability through a one‐step dissolution–evaporation process. This work establishes a versatile and eco‐friendly platform for developing tunable, recyclable piezoelectric materials for next‐generation bioelectronic applications.