Utilizing SELEX procedure for an estrogen binding aptamerAptamers are short sequences of single- stranded nucleic acid sequences that can fold into novel three-dimensional shapes. These structures can be used to capture molecules such as steroids. In this project, SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is used in vitro to select for aptamers within a pool of synthetic nucleic acids that can capture estrogen molecules.