The slide surface, the spotting buffer, the print head, and the spotting pins are critical components for reproducible, high-quality microarray printing. The laboratory staff at the Bauer Core has tested different spotting pins, spotting buffers, and slide coatings and can advise users as to the best combination for their application.
The type of slide to use depends on the chemistry of the products to be printed. When printing amine-modified oligonucleotides, one should use either aldehyde- or epoxy-coated slides, which will react with the amine group on the oligonucleotide. When printing non-modified oligonucleotides or PCR products one should use either poly-lysine or aminosilane-coated slides. The coating on these slides gives them a positive charge which enables them to bind negatively charged DNA. These slides are available from several vendors at costs ranging from $6 to $11 per slide.