In vitro assessment of the biocompatibility of chemically modified GaAs surfaces

Abstract

GaAs has excellent optical, electrical, and mechanical properties and shows promise to be used in the fabrication of novel devices. However, the unprotected GaAs surface can release heavy metal compounds such as AsO x, which are toxic to living cells. A promising approach to reduce or eliminate this release relies on the passivation of the GaAs surface using different chemical approaches. In this work, we compared three different passivation methods aimed at enhancing the viability of cells on GaAs. Protective layers composed of self-assembled alkyl thiols, polypeptides, thick polymer layers, and shells of polyelectrolytes were tested. We confirmed that the GaAs surface can be made biocompatible for several days based on in vitro tests with HeLa and KB cells. In addition, we compared the cell spreading behavior on the GaAs substrates modified by different chemical approaches. Our results suggest that when the toxicity of the GaAs surface is reduced or eliminated, the cells' viability and spreading depend on the chemical and topographical nature of the surface.

Inorganic material coatings and their effect on cytotoxicity

“…The PAH/PSS polyelectrolyte coatings were cytotoxic while the peptide coating (at a relatively high concentration) was not toxic. 41…”

Perspective on Thin Film Waveguides for on-Chip Mid-Infrared Spectroscopy of Liquid Biochemical Analytes

“…The substrate is generally an alloy of GaAs with a refractive index close to that of the waveguide core, so that thick films are needed, resulting in expensive and time-consuming fabrication, and weaker evanescent interaction. Moreover, GaAs is not biocompatible and can release toxic substances such as As or AsO x into aqueous analytes which can, for example, lead to cell death. , …”

“…Moreover, GaAs is not biocompatible and can release toxic substances such as As or AsO x into aqueous analytes which can, for example, lead to cell death. 37,38 Chalcogenides. Planar waveguides of mercury cadmium telluride (MCT) were fabricated as on-chip MIR transducers and evanescent field sensing of acetone was demonstrated by depositing a drop of solution on the waveguide.…”

Wireless Microstimulators for Neural Prosthetics

“…It was shown that GaAs surfaces can be coated with various biocompatible materials to prevent the release of toxic substances. 64 A potential coating material is Parylene C (poly-paraxylylene), which has been widely used as a structural material for bioMEMS systems, and as a coating material in electronic circuits and implantable electrodes. 65 Parylene C has several desirable properties, such as biocompatibility, chemical inertness, high flexibility, and reliable hermetic sealing of the electronic implantable systems.…”