Biomimetic Superhydrophobic Surfaces Patterned with Wettable Spots as Implantable Chips for In Vivo High-content 3d Biomaterials Response Assessment.

Flat patterned superhydrophobic films are herein reported as implantable platforms containing arrays of miniaturized porous scaffolds for the high-throughput in vivo study of biomaterials.  High-throughput platforms are powerful platforms to detect hit conditions showing promising properties. However, high-content analysis of biomaterials has been mostly limited to in vitro testing where crucial information is lost, as the in vivo environment is highly complex. Conventional in vivo testing of biomaterials performance requires the use of high numbers of animals, leading to ethical questions and costly experimentation. In this work, an array of 36 distinct biomaterials was patterned onto biomimetic superhydrophobic platforms. Each biomaterial precursor was dispensed in individual spots with high control of shape and size. Biomaterials were processed as freeze-dried three-dimensional scaffolds and the chips were afterwards implanted subcutaneously in Wistar rats. The presence of inflammatory cells was assessed on-chip by performing immunocytochemistry in the miniaturized biomaterials to identify lymphocytes and activated macrophages. Histological sections of the tissues surrounding the implants were also analyzed. Localized and independent inflammatory responses were detected and the integration of this data with control data proved that these chips are robust platforms for the rapid screening of early-stage in vivo biomaterials’ response.