Taale Mohammadreza, Krüger Diana, Ossei-Wusu Emmanuel, Schütt Fabian, Rehman Muhammad Atiq Ur, Mishra Yogendra Kumar, Marx Janik, Stock Norbert, Fiedler Bodo, Boccaccini Aldo R, Willumeit-Römer Regine, Adelung Rainer, Selhuber-Unkel Christine
Biocompatible Nanomaterials, Institute for Materials Science, Kiel University, Kaiserstr. 2, D-24143 Kiel, Germany.
Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Division Metallic Biomaterials, Max-Planck-Str. 1, D-21502 Geesthacht, Germany.
ACS Biomater Sci Eng. 2019 Sep 9;5(9):4393-4404. doi: 10.1021/acsbiomaterials.9b00102. Epub 2019 Jul 19.
The coating of porous scaffolds with nanoparticles is crucial in many applications, for example to generate scaffolds for catalysis or to make scaffolds bioactive. A standard and well-established method for coating surfaces with charged nanoparticles is electrophoresis, but when used on porous scaffolds, this method often leads to a blockage of the pores so that only the outermost layers of the scaffolds are coated. In this study, the electrophoretic coating process is monitored in situ and the kinetics of nanoparticle deposition are investigated. This concept can be extended to design a periodic electrophoretic deposition (PEPD) strategy, thus avoiding the typical blockage of surface pores. In the present work we demonstrate successful and homogeneous electrophoretic deposition of hydroxyapatite nanoparticles (HAn, diameter ≤200 nm) on a fibrous graphitic 3D structure (ultralightweight aerographite) using the PEPD strategy. The microfilaments of the resulting scaffold are covered with HAn both internally and on the surface. Furthermore, protein adsorption assays and cell proliferation assays were carried out and revealed that the HAn-decorated aerographite scaffolds are biocompatible. The HAn decoration of the scaffolds also significantly increases the alkaline phosphatase activity of osteoblast cells, showing that the scaffolds are able to promote their osteoblastic activity.
用纳米颗粒对多孔支架进行涂层处理在许多应用中都至关重要，例如制备用于催化的支架或使支架具有生物活性。一种用带电纳米颗粒对表面进行涂层处理的标准且成熟的方法是电泳，但在多孔支架上使用时，这种方法常常会导致孔隙堵塞，以至于只有支架的最外层被涂层。在本研究中，对电泳涂层过程进行了原位监测，并研究了纳米颗粒沉积的动力学。这一概念可扩展用于设计一种周期性电泳沉积（PEPD）策略，从而避免表面孔隙的典型堵塞。在当前工作中，我们展示了使用PEPD策略成功且均匀地将羟基磷灰石纳米颗粒（HAn，直径≤200 nm）电泳沉积在纤维状石墨三维结构（超轻气凝胶石墨）上。所得支架的微丝在内部和表面都覆盖有HAn。此外，还进行了蛋白质吸附试验和细胞增殖试验，结果表明经HAn修饰的气凝胶石墨支架具有生物相容性。支架的HAn修饰还显著提高了成骨细胞的碱性磷酸酶活性，表明该支架能够促进其成骨活性。
