Femtosecond Laser-Assisted Free-Form 3D Printing on Fiber Tip for Micro Fluidic Sensing Applications

The rapid expansion of modern cities has significantly intensified heavy metal pollution in soil, the atmosphere, and particularly in aquatic environments, underscoring the urgent need for efficient pollutants detection methods [1]. Meanwhile, optical fibers, introduced nearly 40 years ago, are recognized as a cornerstone of innovation in sensing and instrumentation, driving remarkable progress in both academic and industrial research [2]. Recent progress in laser-assisted 3D printing technologies has further expanded the possibilities for a precise and dedicated patterning on fiber tips using polymer-based materials [3]. However, such materials may degrade under laser exposure. To overcome this limitation, hybrid organic-inorganic resins have been developed offering durable, cost-effective and eco-friendly solution to propose long-lasting structures [4].