Novel Nanocomposite PLA Films with Lignin/Zinc Oxide Hybrids: Design, Characterization, Interaction with Mesenchymal Stem Cells

Francesca Luzi; Ilaria Tortorella; Alessandro Di Michele; Franco Dominici; Chiara Argentati; Francesco Morena; Luigi Torre; Debora Puglia; Sabata Martino

doi:10.3390/nano10112176

Novel Nanocomposite PLA Films with Lignin/Zinc Oxide Hybrids: Design, Characterization, Interaction with Mesenchymal Stem Cells

Nanomaterials (Basel). 2020 Oct 31;10(11):2176. doi: 10.3390/nano10112176.

Authors

Francesca Luzi¹, Ilaria Tortorella², Alessandro Di Michele³, Franco Dominici¹, Chiara Argentati², Francesco Morena², Luigi Torre¹, Debora Puglia¹, Sabata Martino^{2

4}

Affiliations

¹ Department of Civil and Environmental Engineering, Materials Engineering Center, UdR INSTM, University of Perugia, Strada di Pentima 4, 05100 Terni, Italy.
² Department of Chemistry, Biology and Biotechnologies, University of Perugia, 06123 Perugia, Italy.
³ Department of Physics and Geology, University of Perugia, Via Pascoli, 1, 06123 Perugia, Italy.
⁴ CEMIN, Center of Excellence on Nanostructured Innovative Materials, Via del Giochetto, 06123 Perugia, Italy.

Abstract

Herein we present the production of novel nanocomposite films consisting of polylactic acid (PLA) polymer and the inclusion of nanoparticles of lignin (LNP), ZnO and hybrid ZnO@LNP (ZnO, 3.5% wt, ICP), characterized by similar regular shapes and different diameter distribution (30-70 nm and 100-150 nm, respectively). The obtained set of binary, ternary and quaternary systems were similar in surface wettability and morphology but different in the tensile performance: while the presence of LNP and ZnO in PLA caused a reduction of elastic modulus, stress and deformation at break, the inclusion of ZnO@LNP increased the stiffness and tensile strength (σ_b = 65.9 MPa and E_Young = 3030 MPa) with respect to neat PLA (σ_b = 37.4 MPa and E_Young = 2280 MPa). Neat and nanocomposite PLA-derived films were suitable for adult human bone marrow-mesenchymal stem cells and adipose stem cell cultures, as showed by their viability and behavior comparable to control conditions. Both stem cell types adhered to the films' surface by vinculin focal adhesion spots and responded to the films' mechanical properties by orchestrating the F-actin-filamin A interaction. Collectively, our results support the biomedical application of neat- and nanocomposite-PLA films and, based on the absence of toxicity in seeded stem cells, provide a proof of principle of their safety for food packaging purposes.

Keywords: Poly(lactic acid); biomedical application; bone-marrow mesenchymal stem cells (hBM-MSCs); food packaging application; human adult adipose stem cells (hASCs); lignin nanoparticles; zinc oxide nanoparticles.