Fabrication of Quasi‐2D Shape‐Tailored Microparticles using Wettability Contrast‐Based Platforms

• Published in: Advanced materials (Weinheim) 2021-04, Vol.33 (14), p.e2007695-n/a
• Main Authors: Neto, Mafalda D., Stoppa, Aukha, Neto, Miguel A., Oliveira, Filipe J., Gomes, Maria C., Boccaccini, Aldo R., Levkin, Pavel A., Oliveira, Mariana B., Mano, João F.
• Format: Article
• Language: English
• Subjects: bioinspired surfaces; Circles (geometry); Energy harvesting; Hexagons; Microparticles; Object recognition; oleophobic patterned surfaces; Platforms; quasi‐2D nanostructures; Spheroids; Stem cells; Triangles; ultrathin microparticles; Wettability; wettable–dewettable contrast
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202007695

The ability to fabricate materials with ultrathin architectures enables the breakthrough of low‐dimensional structures with high surface area that showcase distinctive properties from their bulk counterparts. They are exploited in a wide range of fields, including energy harvesting, catalysis, and biomedicine. Despite such versatility, the fine tuning of the lateral dimensions and geometry of these structures remains challenging. Prepatterned platforms gain significant attention as enabling technologies to process materials with highly controlled shapes and dimensions. Herein, different nanometer‐thick particles of various lateral sizes and geometries (e.g., squares, circles, triangles, hexagons) are processed with high precision and definition, taking advantage of the wettability contrast of oleophilic–oleophobic patterned surfaces. Quasi‐2D polymeric microparticles with high shape‐ and size‐fidelity can be retrieved as freestanding objects in a single step. These structures show cell‐mediated pliability, and their integration in gravity‐enforced human adipose‐derived stem cell spheroids leads to an enhanced metabolic activity and a modulated secretion of proangiogenic factors. Thin polymeric films with well‐defined lateral size and geometry are fabricated taking advantage of the wettability contrast of oleophilic–oleophobic patterned surfaces. Cells mediate the pliability of quasi‐2D films, and their integration in 3D cellular aggregates leads to enhanced cell metabolic activity and secretion of vascular endothelial growth factor.