Microstructured Reactors Designed by Stereolithography and Characterized by Fluorescent Probes

Abstract

The main objective of this research was to define a structured and functionalized support for future biomedical applications (model of “low-density bioarray”). The experiments were carried out by using stereolithography process with a special SU-8 photoresist and the reproducibility of the method was studied by analyzing the surface profile of the support. Finally, a matrix of regular controlled sized wells was fabricated. Chemical reactions leading to covalent grafting were run to demonstrate that the inner surface of the wells remains still reactive after polymerization. The grafting of fluorophores with carboxylic functions activated by N-hydroxysuccinimide was studied as function of time, in order to determine the best reactions, conditions. Then, the grafting of two distinct fluorescent probes was led simultaneously inside the wells, showing the possibility of spatial localization of diverse reactions on the same support. The covalent and localized bindings were confirmed by fluorescence spectroscopy and microscopy analyses.