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Abstract Microbubbles are an important tool due to their unique mechanical, acoustic, and dynamical properties. Yet, it remains challenging to generate microbubbles quickly in a parallel, biocompatible, and controlled manner. Here, we present an opto-electrochemical method that combines precise light-based projection with low-energy electrolysis, realizing defined microbubble patterns that in turn trigger assembly processes. The size of the bubbles can be controlled from a few to over hundred micrometers with a spatial accuracy of ~2 μm. The minimum required light intensity is only ~0.1 W/cm², several orders of magnitude lower compared to other light-enabled methods. We demonstrate the assembly of prescribed patterns of 40-nm nanocrystals, 200 nm extracellular vesicles, polymer nanospheres, and live bacteria. We show how nanosensor-bacterial-cell arrays can be formed for spectroscopic profiling of metabolites and antibiotic response of bacterial assemblies. The combination of a photoconductor with electrochemical techniques enables low-energy, low-temperature bubble generation, advantageous for large-scale, one-shot patterning of diverse particles in a biocompatible manner. The microbubble-platform is highly versatile and promises new opportunities in nanorobotics, nanomanufacturing, high-throughput bioassays, single cell omics, bioseparation, and drug screening and discovery. 

The rapid advancement of nanotweezers for wireless manipulation of artificial micro‐ and nanoparticles has unlocked unprecedented possibilities in biomedicine. This review delves into optical, electric, and magnetic tweezers, emphasizing their roles in controlling single particles with micro/nanoscale features as miniaturized tools. Instead of providing a comprehensive review, this work highlights a select number of representative historical and contemporary examples of each type of tweezer, covering their rudimental working mechanisms, experimental setups, performance characteristics, and niche biomedical applications. Particularly, the focus lies in providing a quantitative comparison of the performances in spatial precision and degrees of freedom in controlling single particles, along with associated challenges and prospects.