Microarrays formed by microfluidic spinning as multidimensional microreactors

The exploration of methods allowing chemical reactions to be carried out at ultrasmall scales is of great scientific and technological interest. We report herein a microfluidic spinning technique for the fabrication of softened-polymer microarrays for use as multidimensional microreactors and the application of these microreactors in the synthesis of fluorescent nanocrystals. Highly aligned microarrays and controlled-angle grids were readily constructed from microfluidically spun polyvinylpyrrolidone (PVP) microfibers. One-zero dimensional (1D-0D), one-one dimensional (1D-1D), and one-two dimensional (1D-2D) microreactors were then produced by the intersections between microfibers and droplets, crossed microfibers, and microfibers and a PVP film, respectively; each component can be doped with different reagents. Specific examples show that these multidimensional microreactors enable the in situ generation of fluorescent nanocrystals without ligands within minutes. At a critical juncture: Well-defined fluorescent microarrays with various patterns were fabricated in a controlled manner by a rapid and straightforward microfluidic spinning technique. By the use of appropriately doped components, the intersections of the multidimensional microarrays served as microreactors for environmentally friendly chemical reactions to form fluorescent nanocrystals.