Amino Acid-Functionalized Polyelectrolyte Films as Bioactive Surfaces for Cell Adhesion

Abstract

Surfaces were prepared with polyelectrolyte derivatives of poly(styrene-alt-maleic anhydride) (PSMA) functionalized with amino acids of different hydropathy indices, with the aim of evaluating the effect of the chemical functionality of polyelectrolytes on SH-SY5Y neuroblastoma cell adhesion. Functionalizing PSMA derivatives with L-glutamine, L-methionine and L-tyrosine yielded PSMA-Gln, PSMA-Met and PSMA-Tyr polyelectrolytes, respectively. We first studied the adsorption behavior of PSMA functionalized with amino acids on silicon wafer surfaces modified with 3aminopropyltriethoxysilane (APS) at pH 4.0 and 7.0 and at low and high ionic strength. The highest rate of polyelectrolyte adsorption was at pH 4.0 and high ionic strength, and was higher with the glutamine and tyrosine films. The advance contact angles (qA) of the polyelectrolyte surfaces showed a moderate effect of ionic strength and pH on polyelectrolyte film wettability, with PSMA-Tyr being slightly more hydrophobic. AFM images of the polyelectrolyte surfaces showed two types of morphology: the welldefined globular nanostructure of PSMA-Met and PSMA-Tyr, and the densely packed nanofibrous-like structure of PSMA-Gln. The highest level of ionic strength caused a slight decrease in size of the nanostructure that formed the surface domains, which was reflected in the degree of surface roughness. Cell adhesion assays with polyelectrolyte film showed that SH-SY5Y neuroblastoma cells cultured on PSMA-Met present a well-extended morphology characterized by a stellate shape, with five or more actin-rich thin processes, while SH-SY5Y cells that where seeded on PSMA-Gln and PSMA-Tyr have a round morphology, with fewer and shorter processes. These results indicate that it is possible to modulate the surface characteristics of polyelectrolyte films based on their chemical functionality and environmental parameters such as pH and ionic strength, in order to evaluate their effect on cell adhesion. Thus, surfaces prepared from polyelectrolytes functionalized with amino acids are an attractive and simple platform for cell adhesion, which can be used in developing biomaterials with modulated surface properties.

Fabrication and functionalization of 3D-printed soft and hard scaffolds with growth factors for enhanced bioactivity

“…50 RGD as a bio mimetic peptide can increase the cell adhesion and attachment on the matrix surface by preventing cell apoptosis. 51 To improve the osteogenesis of the hard tissue implants we conjugated RGD on dopamine surface. RGD chemical structure shown in Fig.…”

Biocompatible Self-Healing Coating Based on Schiff Base for Promoting Adhesion of Coral Cells

“…Sample preparation was performed on the surface of silicon, and AFM observations were performed immediately after carefully blowing with nitrogen stream. The AFM images shown in Figure prove the nanoscale roughness surface morphologies of layer-by-layer self-assembled films of all unmodified and modified surfaces . Fairly regular and homogeneous polymer deposition was observed in both dopamine-modified and lysozyme-modified films.…”

“…The AFM images shown in Figure 4 prove the nanoscale roughness surface morphologies of layer-by-layer self-assembled films of all unmodified and modified surfaces. 39 Fairly regular and homogeneous polymer deposition was observed in both dopamine-modified and lysozyme-modified films. The roughness degree (R max ) of the three types of films prepared was 57.7, 25.1, and 57.7 nm, respectively.…”

Conformational Changes of Poly(Maleic Anhydride-alt-styrene) Modified with Amino Acids in an Aqueous Medium and Their Effect on Cytocompatibility and Hemolytic Response

“…Synthesis and characterization of PSMA-Gln, PSMA-Met, and PSMA-Tyr were performed according to our previous report. 25 The PEs PSMA-Phe and PSMA-Gly were synthesized and characterized in the same manner.…”

“…Modifying the film surface properties, such as wettability, surface energy, hysteresis, roughness, and charge density, caused various effects on the adhesion of human SH-SY5Y neuroblastoma cells, cell proliferation, and differentiation. 25 A surface based on the PEs obtained from the poly(maleic anhydride-alt-vinylpyrrolidone), which was functionalized with amino acids that had different hydropathy indices, was used for the adsorption of the enzyme glucose 6-phosphate dehydrogenase from Leuconostoc mesenteroides (LmG6PD). The results indicate that the polarity of the side chain of the amino acid in the PE affected the quantity of LmG6PD adsorbed as well as its specific activity, demonstrating that films prepared from poly(MA-alt-VP) functionalized with methionine duplicate the specific activity of the adsorbed enzyme compared to the other systems studied and provide the best enzymatic performance.…”