Development of Sphere-Polymer Brush Hierarchical Nanostructure Substrates for Fabricating Microarrays with High Performance

Abstract

In this work, a sphere-polymer brush hierarchical nanostructure-modified glass slide has been developed for fabricating high-performance microarrays. The substrate consists of a uniform 160 nm silica particle-self-assembled monolayer on a glass slide with a postcoated poly(glycidyl methacrylate) (PGMA) brush layer (termed PGMA@3D(160) substrate), which can provide three-dimensional (3D) polymer brushes containing abundant epoxy groups for directly immobilizing various biomolecules. As a typical example, the interactions of three monosaccharides (4-aminophenyl β-d-galactopyranoside, 4-aminophenyl β-d-glucopyranoside, and 4-aminophenyl α-d-mannopyranoside) with two lectins (biotinylated ricinus communis agglutinin 120 and biotinylated concanavalin A from Canavalia ensiformis) have been assessed by PGMA@3D(160) substrate-based carbohydrate microarrays. The carbohydrate microarrays show good selectivity, strong multivalent interaction, and low limit of detection (LOD) in the picomolar range without any signal amplification. Furthermore, the proposed sphere-polymer brush hierarchical nanostructure substrates can be easily extended to fabricate other types of microarrays for DNA and protein detection. PGMA@3D(160) substrate-based microarrays exhibit higher reaction efficiencies and lower LODs (by at least 1 order of magnitude) in comparison to those of two-dimensional microarrays, which are fabricated on planar epoxy substrates, making it a promising platform for bioanalytical and biomedical applications.

Carbohydrate microarrays fabricated on poly(2-methylacrylic acid)-based substrates for analysis of carbohydrate–protein interactions

“…3a, inset). The sensitivity is improved 5 times compared to those of reported sphere-polymer brushbased microarrays 11 and 10 times compared to those of pHEMA-CC-based microarrays. 15 Consequently, the consumption of carbohydrate samples can be down to the level of picomoles when the manual spotting volume is several microliters.…”

“…20Â saline sodium citrate (SSC) buffer, and synthetic DNA oligomers were purchased from Sangon, Ltd (Shanghai, China). The ssDNA base sequences were as follows: 11 the probe ssDNA has a base sequence of 5 0 -AGAGACTGGCGCTTTTT-NH 2 -3 0 (Ps); the target ssDNA has a base sequence of 5 0 -GCGCCAGTCTCTCCCAGGACAGGCA-3 0 (Ts); and the labeling ssDNA has a base sequence of 5 0 -Alexa Fluor-T 10 TGCCTGTCCTGGG-3 0 (Ls). Bovine serum albumin (BSA) was purchased from Solarbio (Beijing, China).…”

“…Liu et al adopted silica nanoparticle-coated glass substrates with post-modification with a poly(glycidylmethacrylate) brush layer for carbohydrate microarray fabrication so as to improve the carbohydrate loading capacity on the substrates, and the obtained carbohydrate microarrays exhibited good sensitivity and strong multivalent interactions. 11 Lin et al adopted molecular scaffolds to adjust the distances between the carbohydrate ligands to match the binding sites on glycan binding proteins (GBPs) in order to guarantee multivalent binding. 12 On the other hand, suppressing nonspecific adsorption of GBPs on microarrays can dramatically reduce the background noise.…”

Preparation of a poly (PEGDA‐co‐GMA) thin hydrogel matrix for oligonucleotide microarray applications

“…18 The 3D microarray on a glass slide can be fabricated by increasing its surface roughness, by plasma treatment of polymer coated glass slide to generate micro-nanotexture, 19 or via self-assembly of monolayer silica nanoparticles on the surface. 20 In addition, because of the excellent biocompatibility and antifouling property of hydrogel layers, which was considered to be an ideal substrate for biochips. 21 Unlike other 3D microarrays with coarse surface but immobilized biomolecules on the 1D or 2D way by reacting with surface functional groups or polymer brushes, the hydrogel layer provides a true 3D environment for probe immobilization, which may decrease the steric hindrance between the target analytes and substrate surface.…”

“…The hydrogel layer provides a true 3D environment for probe immobilization, which may decrease the steric hindrance between the target analytes and substrate surface. 20 Therefore, many different kinds of hydrogels have used as substrate to immobilize oligonucleotide probes such as poly (ethylene glycol) diacrylate hydrogel, 22 agarose gel 23 and acrylamide gel. 24,25 Notwithstanding this, most hydrogel coatings on glass slide have thicknesses of tens to hundreds of micrometers, which is too thick and hinders the diffusion of analytes.…”