Center for Advanced Laser Technologies (CETAL), National Institute for Laser, Plasma and Radiation Physics, Magurele, RO-077125 Bucharest, Romania.
Faculty of Applied Sciences, University Politehnica of Bucharest, RO-060042 Bucharest, Romania.
Int J Mol Sci. 2018 Feb 7;19(2):495. doi: 10.3390/ijms19020495.
We designed, fabricated and optimized 3D biomimetic magnetic structures that stimulate the osteogenesis in static magnetic fields. The structures were fabricated by direct laser writing via two-photon polymerization of IP-L780 photopolymer and were based on ellipsoidal, hexagonal units organized in a multilayered architecture. The magnetic activity of the structures was assured by coating with a thin layer of collagen-chitosan-hydroxyapatite-magnetic nanoparticles composite. In vitro experiments using MG-63 osteoblast-like cells for 3D structures with gradients of pore size helped us to find an optimum pore size between 20-40 µm. Starting from optimized 3D structures, we evaluated both qualitatively and quantitatively the effects of static magnetic fields of up to 250 mT on cell proliferation and differentiation, by ALP (alkaline phosphatase) production, Alizarin Red and osteocalcin secretion measurements. We demonstrated that the synergic effect of 3D structure optimization and static magnetic stimulation enhances the bone regeneration by a factor greater than 2 as compared with the same structure in the absence of a magnetic field.
我们设计、制造和优化了 3D 仿生磁性结构，以在静态磁场中刺激成骨。这些结构是通过双光子聚合 IP-L780 光聚合物的直接激光写入制造的，基于组织在多层结构中的椭圆形、六方单元。通过涂覆一层薄薄的胶原-壳聚糖-羟基磷灰石-磁性纳米颗粒复合材料来保证结构的磁性活性。使用 MG-63 成骨样细胞进行具有孔径梯度的 3D 结构的体外实验帮助我们找到了最佳孔径在 20-40 µm 之间。从优化的 3D 结构开始，我们通过碱性磷酸酶 (ALP) 生产、茜素红和骨钙素分泌测量，定性和定量地评估了高达 250 mT 的静态磁场对细胞增殖和分化的影响。我们证明，3D 结构优化和静态磁刺激的协同作用使骨再生增强了超过 2 倍，与没有磁场的相同结构相比。
