Surface functionalizing method for use in high-throughput in situ synthesis of nucleic acids by 3D inkjet printing

A surface functionalizing method for use in high-throughput in situ synthesis of nucleic acids by 3D inkjet printing, consisting of the following steps:

• 1) subjecting a surface of a substrate to hydroxyl enrichment treatment;
• 2) adding hydrophobic molecules to the surface of the substrate, wherein the hydrophobic molecules do not react with phosphoramidite monomers;
• 3) spraying, by a multi-channel piezoelectric inkjet head assembly, an etching ink to a predetermined area on the surface of the substrate for micro-etching,
• wherein the etching ink is prepared with a fluoride compound,
• wherein the fluoride compound reacts with the hydrophobic molecules, thereby selectively removing the hydrophobic molecules and exposing hydroxyl groups on the surface of the substrate;
• and
• 4) applying hydrophilic molecules to the entire area of the surface of the substrate, reacting the hydrophilic molecules applied to the etched predetermined area with the hydroxyl groups exposed through micro-etching, and rinsing the remaining hydrophilic molecules with acetonitrile solution, by which functionalizing of the surface of the substrate is realized, wherein the hydrophilic molecules only react with hydroxyl groups, and do not react with the hydrophobic molecules, wherein the hydrophilic molecules are selected from the group consisting of
• 3-glycidyloxypropyltrimethoxysilane,
• N-(3-triethoxysilylpropyl)-4-hydroxybutyramide,
• 11-acetoxyundecyltriethoxysilane,
• n-decyltriethoxysilane,
• (3-aminopropyl)trimethoxysilane,
• 3-iodo-propyltrimethoxysilane, and
• mixtures thereof.