Parallel Control over Surface Charge and Wettability Using Polyelectrolyte Architecture: Effect on Protein Adsorption and Cell Adhesion

Abstract

Surface charge and wettability, the two prominent physical factors governing protein adsorption and cell adhesion, have been extensively investigated in the literature. However, a comparison between these driving forces in terms of their independent and cooperative effects in affecting adhesion is rarely explored on a systematic and quantitative level. Herein, we formulate a protocol that features two-dimensional control over both surface charge and wettability with limited cross-parameter influence. This strategy is implemented by controlling both the polyion charge density in the layer-by-layer (LbL) assembly process and the polyion side-chain chemical structures. The 2D property matrix spans surface isoelectric points ranging from 5 to 9 and water contact angles from 35 to 70°, with other interferential factors (e.g., roughness) eliminated. The interplay between these two surface variables influences protein (bovine serum albumin, lysozyme) adsorption and 3T3 fibroblast cell adhesion. For proteins, we observe the presence of thresholds for surface wettability and electrostatic driving forces necessary to affect adhesion. Beyond these thresholds, the individual effects of electrostatic forces and wettability are observed. For fibroblast, both surface charge and wettability have an effect on its adhesion. The combined effects of positive charge and hydrophilicity lead to the highest cell adhesion, whereas negative charge and hydrophobicity lead to the lowest cell adhesion. Our design strategy can potentially form the basis for studying the distinct behaviors of electrostatic force or wettability driven interfacial phenomena and serve as a reference in future studies assessing protein adsorption and cell adhesion to surfaces with known charge and wettability within the property range studied here.

Effect of Different Crosslinking Strategies on Physical Properties and Biocompatibility of Freestanding Multilayer Films Made of Alginate and Chitosan

“…In this case, the net charge of the films' surface is decreased due to the engagement of carboxylic groups of ALG with Ca ions. That leads to reduced cell attachment and growth on the surface …”

“…That leads to reduced cell attachment and growth on the surface. [40,41] Based on both MTT and QBlue assay results we can conclude that films do not have any toxic effect on NHDF cells and at the same time do not favor their adhesion and proliferation on their surface. Both outcomes deem these films appropriate candidates for wound dressings.…”

Biomimetic neural scaffolds: a crucial step towards optimal peripheral nerve regeneration

“…93 Chemical modifications are also used to incorporate biomolecules, including wet-chemical methods (such as hydrolysis and aminolysis), 94 ozone treatment, 95 UVtreatment and photo-grafting, 96 self-assembly, 97 and plasma treatment. 92 Physical properties such as wettability can be modified via chemistry, which can also be used to enable additional binding of ECM proteins and biomimetic (discussed below) to the scaffold surface.…”

Amphiphilic Polymer Platforms: Surface Engineering of Films for Marine Antibiofouling

“…Whilst it is arguably a combination of features that will finally intervene in the overall performance of a coating, the development of a “model” surface in which a single surface property is systematically changed, while keeping the others constant, is a tool to identify the influence of individual surface features on biofouling formation, settlement, and removal. Although it is difficult to compare different driving forces for surface fouling in terms of their independent and cooperative effects in affecting adhesion on a quantitative level, comprehensive investigations would eventually lead to a knowledge‐based, exploitable understanding for the development of practical coatings for application to structures for the aquatic environment on a large industrial scale for different end uses.…”

“…Whilst it is arguably a combination of features that will finally intervene in the overall performance of a coating, the development of a "model" surface in which a single surface property is systematically changed, while keeping the others constant, is a tool to identify the influence of individual surface features on biofouling formation, settlement, and removal. Although it is difficult to compare different driving forces for surface fouling in terms of their independent and cooperative effects in affecting adhesion on a quantitative level, [26] comprehensive investigations would eventually lead to a knowledgebased, exploitable understanding for the development of practical coatings for application to structures for the nanoscale dimensions [53][54][55][56][57] and photocatalytic nanoparticles, [21,58,59] to self-polishing silyl ester polymers. [60] The engineering of the surface and interface of amphiphilic polymers, which combine both hydrophilic and hydrophobic components in one chemical architecture, has attracted attention in the last decade and is currently conceived as one more promising strategy to implement special interface functions in a variety of industries and technologies.…”