Integrated Hydrogel Patterning and Dynamic Microparticle Manipulation Using Optoelectronic Tweezers

Abstract

This paper presents an integrated optoelectronic tweezers platform that unifies hydrogel microstructure fabrication with subsequent dynamic microsphere manipulation, enabled by a dual-wavelength optical strategy for seamless and programmable control. Initial tests in low-conductivity aqueous media confirmed high-fidelity OET patterning, with edge roughness below 20 μm. Using a biocompatible GelMA--LAP system, we achieved: (i) precise single-region hydrogel structures (hexagram patterns, average deviation 2.779 μm); (ii) scalable, customizable assemblies of complex topologies, including gear and maze arrays; and (iii) coordinated navigation of single, double, and triple microspheres within hydrogels, with triple-sphere velocity differences <0.9 μm/s. This approach overcomes the conventional OET limitation of decoupled photolithography and particle manipulation, integrating structure fabrication with dynamic control. It provides a versatile, reproducible platform for tissue engineering scaffolds, targeted drug delivery, and multi-particle coordination.