Fabrication of (bio)molecular patterns with contact printing techniques

Patterns are a collection of forming units predictably repeated over a defined magnitude. Researchers have used patterns to guarantee the functionality and repeatability of their study. For that, the obtained data is purposely compared over and over in hope that the results are comparable. Two main research approaches are based on patterns: The initial requires a single substrate with localized and repeated units to create multiple testing sites, obtaining a repeated, multi-analysis system. The second approach uses fixed localization with different testing motifs, creating a diverse multi-analysis platform. The miniaturization of these assays provides an alternative to reduce cost, maximize efficiency, and increase repeatability. Micropatterns consist on immobilized (bio)molecular motifs constrained in small areas over a solid substrate. These fixed spots provide up to thousands of reaction sites for parallel detection. Micropatterns were first developed to study the interaction between Deoxyribonucleic acid (DNA) strands and the study of the genome. Afterwards, this technology was used to create miniaturized protein patterns. Today, this technology is essential for large-scale and high-throughput biological and biochemical studies. Single-feature microarrays are routinely reproduced at many laboratories using various contact, non-contact, or alternatively methods. The foundation is to transfer a (bio)molecule in a solution onto a solid substrate obtaining a defined feature shape. This Thesis aims to expand the current contact replication techniques for microarray fabrication. Initially, an automatized microcontact printing tool was characterized to create complex patterns on a wide range of substrates. Thiols, silanes, and various biomolecules were printed on glass, silicon oxide or gold. The printing properties were explored to create a definitive protocol for further applications. The effect of the printing force and dwell time were thoroughly studied to form a mathematical expression to understand all the variables involved during contact printing. The miniscule resolution provided by the automatized tool allowed the creation of complex micropatterns with single or multiple printings steps. This tool was later upgraded and fitted with new controllers to create smaller patterns. An alternatively contact printing technique called polymer pen lithography was used to pattern the surface of specialized substrates to create micropatterns on constricted areas