Abstract
Aptamers, often described as "chemical antibodies", are short, single-stranded nucleic acids that can bind target molecules with high affinity and specificity. Due to these properties, aptamers have diverse therapeutic applications. They can function as standalone drugs, serve as carriers for a range of therapeutics including small molecules, nucleic acids, peptides, proteins, and antibodies, or be used to functionalize drug delivery systems such as nanoparticles and bulk biomaterials. This review summarizes these diverse applications and discusses potential challenges associated with aptamers and drug delivery systems more broadly.