Optimization of a new SELEX process for the selection of novel 17ß-estradiol aptamers

Abstract

This thesis project was aimed to develop a new SELEX process for the selection of E2-aptamers in an optimized buffer composed of PBS and 10% ethanol, while Nortestosterone was used as counter molecule. It was hypothesized that such a SELEX can select aptamers with a high affinity and specificity to E2, especially for its hydroxylated aromatic ring A (phenolic group), according to the structural difference between E2 and Nortestosterone. Moreover, it was assumed that optimization of the buffer conditions for SELEX will allow, on the one hand, adequate dissolving of E2, and on the other hand, the selection of aptamers in experimentally realistic conditions. It was expected that selected aptamers in such realistic conditions will show lower unspecific binding and cross-reaction to molecules that are structurally similar to E2. Therefore, a more specific aptamer would be selected to fabricate a more efficient E2 aptasensor.