Abstract
Widely used in various biomedical applications, aptamers are single-stranded DNA or RNA molecules with high specificity and binding affinity to the target molecules, which can be ascribed to their selection by an in vitro process, known as SELEX (systematic evolution of ligands by exponential enrichment). More specifically, cell-based SELEX, which uses whole disease cells as targets, can also produce aptamer probes that effectively differentiate cancer cells from healthy cells. Based on these properties, molecular assemblies can be rationally designed and engineered to fulfil many therapeutic objectives. Therefore, in this review, we describe the most important strategies for the molecular assembly of aptamer-conjugates, including those that involve aptamers, drugs, photosensitizers, and nanoparticles for use in regulating protein function, targeted drug delivery and cancer therapy. Their affinity and specificity to virtually any given protein make it possible to develop aptamers which can inhibit the activity of many pathogenic proteins in the clinic. In this review, we describe different strategies for molecular assembly of aptamers for use as antidotes in regulating protein function. The rational design of aptamers for targeted drug delivery and cancer therapy will also be discussed.