Oberdick Samuel D, Zabow Gary
National Institute of Standards and Technology, Boulder, Colorado, and University of Colorado, Boulder, Coloradoh.
ACS Appl Polym Mater. 2020;2(2). doi: https://doi.org/10.1021/acsapm.9b01109.
We present a generic fabrication scheme to produce polymer microparticles with engineerable, complex shapes. The polymer particles are made from polyethylene glycol based hydrogels using a poly(dimethylsiloxane) (PDMS) molding technique. A simple surface treatment is used to pattern the surface energy of the PDMS molds, engendering the recessed wells in the molds with a higher surface energy than that of the surface. The contrast in surface energy causes hydrogel precursor to wet only the inside of the molds, creating isolated particles after curing with UV light. This eliminates the formation of an interconnecting "scum" layer and allows for fabrication of well-defined, independent particles. We discuss resolution limits for the approach and present a simple strategy for releasing the particles. Finally, to show how the fabrication technique is inherently compatible with further particle modifications, we also demonstrate magnetic functionalization of particles.
我们提出了一种通用的制造方案，用于生产具有可设计复杂形状的聚合物微粒。聚合物颗粒由基于聚乙二醇的水凝胶通过聚二甲基硅氧烷（PDMS）成型技术制成。采用一种简单的表面处理方法来对PDMS模具的表面能进行图案化处理，使模具中的凹陷孔具有比表面更高的表面能。表面能的差异导致水凝胶前体仅润湿模具内部，在紫外光固化后形成孤立的颗粒。这消除了互连“浮渣”层的形成，并允许制造轮廓清晰、独立的颗粒。我们讨论了该方法的分辨率极限，并提出了一种释放颗粒的简单策略。最后，为了展示制造技术如何与进一步的颗粒修饰内在兼容，我们还展示了颗粒的磁功能化。
