Multifaceted arsenal in SELEX nanomedicine

Aptamers, short oligonucleotide sequences that bind specifically to cellular proteins and receptors, are emerging as versatile tools in molecular nanomedicine. Unlike passive tumor targeting via the enhanced permeability and retention (EPR) effect, aptamers enable precise drug delivery, enhancing therapeutic efficacy while minimizing side effects. Developed through the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) process, aptamers offer compact size, robust structure, chemical versatility, and cost-effective synthesis. They serve as effective delivery vehicles for therapeutic molecules, including miRNA, siRNA, and small-molecule drugs, and function as antibody-like ligands for applications in cancer, diabetes, and autoimmune disorders. Since the approval of Macugen, the first aptamer targeting VEGF, aptamers have also shown promise as diagnostic sensors and theranostic agents. This review explores SELEX-derived aptamers in nanomedicine, focusing on their therapeutic and diagnostic roles, particularly in precision cancer therapies. It also addresses challenges such as degradation and clinical translation alongside prospects in vaccines, tissue engineering, and regenerative medicine.