Photoclick chemistry to create dextran-based nucleic acid microarrays

Abstract

Different hydrogels are reported in the literature to create generic platforms for protein microarray applications. Here, a novel strategy was developed to obtain high performance microarrays. It uses a dextran hydrogel to covalently immobilize oligonucleotides and proteins. This method employs aqueous solutions of dextran methacrylate (Dx-MA), which is a biocompatible photopolymerizable monomer. The approach promotes the covalent attachment of the capture probes inside the hydrogel by a thiol-acrylate coupling reaction by light while the dextran polymer is formed. The hydrogel microarrays were prepared on different surfaces, such as Blu-ray disk, polycarbonate or alkene functionalized glass slides, and showed high probe loading capability and good biorecognition yields. This methodology presents certain advantages, like low cost, short analysis times, low limit of detection, and multiplex capability, among others. The confocal fluorescence microscopy analysis demonstrates that the receptor immobilization and the biorecognition event take place inside the hydrogel and not merely on the surface.

The Bioanalytical and Biomedical Applications of Polymer Modified Substrates

“…The as-fabricated PDMAA-5%BP modified substrate exhibited protein-repellent properties for avoiding unspecific adsorption of analyte molecules during the assay, resulting in a simplification of the assaying procedure, a reduction in background signals and an improvement of the detection sensitivity of the microarray immunoassays. Díaz-Betancor et al developed a dextran-based nucleic acid microarray by the immobilization of capture probes in dextran polymer hydrogel via a lightinduced thiol-acrylate coupling reaction and polymerization [140]. This approach enables the detection of as low as 2.92 pg µL −1 miR-182, which is much lower than the normal amount of circulating miRNA (within the ng µL −1 range).…”

In-Situ Monitoring of Real-Time Loop-Mediated Isothermal Amplification with QCM: Detecting Listeria monocytogenes

“…Detection of DNA-based immobilization and hybridization on solid surfaces is the basis of several biotechnological tools and strategies, including DNA microarrays [ 1 , 2 ] and biosensors [ 3 , 4 ]. Previous research on DNA-modified surfaces has largely explored functionalized gold [ 5 ] and other metals [ 6 ].…”