Combinatorial cell–3D biomaterials cytocompatibility screening for tissue engineering using bioinspired superhydrophobic substrates

Abstract

We report on the development of a new array-based screening flat platform with the potential to be used as a high-throughput device based on biomimetic polymeric substrates for combinatorial cell/3D biomaterials screening assays in the context of tissue engineering. Polystyrene was used to produce superhydrophobic surfaces based on the so-called lotus effect. Arrays of hydrophilic regions could be patterned in such surfaces using UV/ozone radiation, generating devices onto which combinatorial hydrogel spots were deposited. The biological performance of encapsulated cells in hydrogels could be tested in an in vitro 3D environment assuming that each site was isolated from the others due to the high contrast of wettability between the patterned spots and the superhydrophobic surroundings. Three different polymers-chitosan, collagen and hyaluronic acid-were combined with alginate in different proportions in order to obtain combinatorial binary alginate-based polymeric arrays. The effect of the addition of gelatin to the binary structures was also tested. The gels were chemically analyzed by FTIR microscopic mapping. Cell culture results varied according to the hydrogel composition and encapsulated cell types (L929 fibroblast cells and MC3T3-E1 pre-osteoblast cells). Cell viability and number could be assessed by conventional methods, such as MTS reduction test and dsDNA quantification. Non-destructive image analysis was performed using cytoskeleton and nuclei staining agents and the results were consistent with the ones obtained by conventional sample-destructive techniques. Briefly, L929 cells showed higher number and viability for higher alginate-content and collagen-containing hydrogels, while MC3T3-E1 showed higher cell viability and cell number in lower alginate-content and chitosan containing hydrogels. The addition of gelatin did not influence significantly cell metabolic activity or cell number in any of the encapsulated cell types.

Fabrication of Hydrogel Particles of Defined Shapes Using Superhydrophobic‐Hydrophilic Micropatterns

“…25,26 Micro-patterned arrays have been generated by immobilizing hydrogels on different micro-domains within a plane surface, and they have been used for disease diagnosis, prognosis, biochemical analysis, and therapeutic regimes, and have become an alternative approach for high-throughput multiplexed assays. [27][28][29][30] Strategies avoiding such 2D fixation of various hydrogels have employed shape-coded hydrogel particles as a suspension microarray format for multiplexed bioassays. 31,32 Here we describe a method for the rapid fabrication of alginate hydrogel particles of defined sizes and shapes using the effect of discontinuous dewetting on an SH-SL microarray combined with the sandwiching method to achieve the simultaneous gelation of the pre-hydrogel droplets.…”

In Vivo High-Content Evaluation of Three-Dimensional Scaffolds Biocompatibility

“…2A-C). [18][19][20] Superhydrophobic surfaces prepared by phase separation methods showed low cell adhesion, 18 including substrates prepared using polystyrene. 22 Therefore, we expect that the scaffold spots could be maintained relatively isolated from each other, avoiding cell passage between spots and minimizing the interaction of the platform with the in vivo milieu.…”

“…[18][19][20] Similar platforms were used in vitro for the study of protein-cell interactions in two-dimensional (2D) environment, cell-laden three-dimensional (3D) hydrogels, and 3D scaffolds. [19][20][21] We hypothesize that the miniaturized size of the patterned biomaterials and the gap maintained between them would be sufficient to observe distinct inflammatory cells recruitment while allowing for isolated responses in each spot. Moreover, the low cell adhesion reported in superhydrophobic surfaces would improve the independency between spots.…”

Biological Applications of Biomimetic Superhydrophobic Surfaces

“…此外, Mano 课题组 [105] 还利用仿生的 PS 超疏水基底进行组织 工程的筛选. 我们相信在不久的将来超疏水性表面还可 作为生物检测和分析的平台, 当然前提条件是我们必须 弄清楚其中的相互作用原理.…”