Light Induced Surface Corrosion of Gallium Arsenide for Immobilization of Oligonucleotide Probes

Abstract

The potential to modify gallium arsenide (GaAs) surfaces with organic molecules provides possibilities to develop biosensors. Thiol-terminated oligonucleotides have been self assembled on GaAs substrates. The homogeneity and surface morphology of oligonucleotide films were investigated using atomic force microscopy (AFM) and fluorescence microscopy. X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were used to determine the surface elemental composition. When in contact with water, the surface of GaAs tended to reorganize. Elemental mapping indicated that the surface was passivated by thiol linked DNA probes. Extended contact with water increased the extent of oxidation and the quantity of immobilized oligonucleotide probes.

Polymer Brushes on GaAs and GaAs/AlGaAs Nanoheterostructures: A Promising Platform for Attractive Detection of Legionella pneumophila

“… 27 − 29 The growing interest in incorporating PBs on semiconductors such as silicon, silicon carbide, and graphene substrates 30 − 32 has been a driving force to the development of optimized incorporation strategies to facilitate biosensor manufacturing and enhance their performance. 33 − 35 …”

“…Recently, the limited success of self-assembled monolayers (SAMs) in sensitive bacteria detection has generated growing interest in exploring alternative architectures, such as those based on polymer brushes (PBs). The attractive three-dimensional character of PBs, combined with the possibility of modifying their end functional groups, has made their use an innovative biosensing strategy, allowing to minimize non-specific interactions, thus leading to optimized biosensing performances and significantly improved limits of detection. − The growing interest in incorporating PBs on semiconductors such as silicon, silicon carbide, and graphene substrates − has been a driving force to the development of optimized incorporation strategies to facilitate biosensor manufacturing and enhance their performance. − …”

Polymer Brush–GaAs Interface and Its Use as an Antibody-Compatible Platform for Biosensing

“…The three-dimensional character of PBs combined with the vast possibilities of modifying functional groups has positioned them as a powerful strategy to minimize nonspecific interactions, leading to optimized biosensing performance and considerable improvements in the limits of detection. − Moreover, PB semiconductor surfaces such as silicon, silicon carbide, and graphene substrates − have attracted considerable attention because of the unique semiconductor surface properties, resulting in several incorporation strategies being developed to facilitate manufacturing protocols while improving the biosensors’ performance. − …”