Magnetically-actuated microcages for cells entrapment, fabricated by laser direct writing via two photon polymerization

Roxana Cristina Popescu; Bogdan Stefanita Calin; Eugenia Tanasa; Eugeniu Vasile; Mona Mihailescu; Irina Alexandra Paun

doi:10.3389/fbioe.2023.1273277

Magnetically-actuated microcages for cells entrapment, fabricated by laser direct writing via two photon polymerization

Front Bioeng Biotechnol. 2023 Dec 19:11:1273277. doi: 10.3389/fbioe.2023.1273277. eCollection 2023.

Authors

Roxana Cristina Popescu^{1

2

3}, Bogdan Stefanita Calin⁴, Eugenia Tanasa⁵, Eugeniu Vasile³, Mona Mihailescu⁵, Irina Alexandra Paun^{4

5}

Affiliations

¹ Department of Bioengineering and Biotechnology, Faculty of Medical Engineering, Politehnica University from Bucharest, Bucharest, Romania.
² Department of Life and Environmental Physics, National Institute for R&D in Physics and Nuclear Engineering "Horia Hulubei", Magurele, Romania.
³ Faculty of Applied Physics, Politehnica University from Bucharest, Bucharest, Romania.
⁴ Center for Advanced Laser Technologies (CETAL), National Institute for Laser, Plasma and Radiation Physics, Magurelee, Romania.
⁵ Department of Physics, Faculty of Applied Physics, Politehnica University from Bucharest, Bucharest, Romania.

Abstract

The manipulation of biological materials at cellular level constitutes a sine qua non and provocative research area regarding the development of micro/nano-medicine. In this study, we report on 3D superparamagnetic microcage-like structures that, in conjunction with an externally applied static magnetic field, were highly efficient in entrapping cells. The microcage-like structures were fabricated using Laser Direct Writing via Two-Photon Polymerization (LDW via TPP) of IP-L780 biocompatible photopolymer/iron oxide superparamagnetic nanoparticles (MNPs) composite. The unique properties of LDW via TPP technique enabled the reproduction of the complex architecture of the 3D structures, with a very high accuracy i.e., about 90 nm lateral resolution. 3D hyperspectral microscopy was employed to investigate the structural and compositional characteristics of the microcage-like structures. Scanning Electron Microscopy coupled with Energy Dispersive X-Ray Spectroscopy was used to prove the unique features regarding the morphology and the functionality of the 3D structures seeded with MG-63 osteoblast-like cells. Comparative studies were made on microcage-like structures made of IP-L780 photopolymer alone (i.e., without superparamagnetic properties). We found that the cell-seeded structures made by IP-L780/MNPs composite actuated by static magnetic fields of 1.3 T were 13.66 ± 5.11 folds (p < 0.01) more efficient in terms of cells entrapment than the structures made by IP-L780 photopolymer alone (i.e., that could not be actuated magnetically). The unique 3D architecture of the microcage-like superparamagnetic structures and their actuation by external static magnetic fields acted in synergy for entrapping osteoblast-like cells, showing a significant potential for bone tissue engineering applications.

Keywords: cells entrapment; laser direct writing; magnetic actuation Justified; microcage-like structures; pattern: clear (white); space after: 0 pt; two photon absorption.

Grants and funding

The authors declare financial support was received for the research, authorship, and/or publication of this article. A part of this work was supported by Romanian Ministry of Research, Innovation and Digitalization under Romanian National NUCLEU Program LAPLAS VII–contract no. 30N/2023. RCP declares funding by Romanian Ministry of Research, Innovation and Digitalization under Romanian National NUCLEU PN-23-21-02-02.