Direct covalent attachment of DNA microarrays by rapid thiol-ene "click" chemistry

[EN] A rapid strategy for the covalent immobilization of DNA onto silicon-based materials using the UV-initiated radical thiol-ene reaction is presented in this study. Following this approach, thiol- and alkene-modified oligonucleotide probes were covalently attached in microarray format, reaching immobilization densities around 6 pmol-cm(-2). The developed methodology presents the advantages of spatially controlled probe anchoring (using a photomask), direct attachment without using cross-linkers (one-pot fashion), and short irradiation times (20 min). Using the described strategy, hybridization efficiencies up to 65% with full complementary strands were reached. The approach was evaluated by scoring single-base pair mismatches with discrimination ratios around 15. Moreover, the efficacy of the proposed DNA detection scheme is further demonstrated through the assay on a genomic target of bacterial Escherichia coli.Financial support from Ministerio de Ciencia e Innovacion (CTQ2010-15943) and Generalitat Valenciana (PROMETEO/2010/008 and ACOMP/2012/158) is acknowledged. The authors are grateful to the Servei d'Espectrometria de Masses of the Universitat de Barcelona for the spectroscopic facilities.Escorihuela Fuentes, J.; Bañuls Polo, M.; Grijalvo-Torrijo, S.; Eritja, R.; Puchades, R.; Maquieira Catala, Á. (2014). Direct covalent attachment of DNA microarrays by rapid thiol-ene "click" chemistry. Bioconjugate Chemistry. 25(3):618-627. https://doi.org/10.1021/bc500033dS61862725