Recent Progress in Aptamer‐Based Functional Probes for Bioanalysis and Biomedicine

Abstract

Nucleic acid aptamers are short synthetic DNA or RNA sequences that can bind to a wide range of targets with high affinity and specificity. In recent years, aptamers have attracted increasing research interest due to their unique features of high binding affinity and specificity, small size, excellent chemical stability, easy chemical synthesis, facile modification, and minimal immunogenicity. These properties make aptamers ideal recognition ligands for bioanalysis, disease diagnosis, and cancer therapy. This review highlights the recent progress in aptamer selection and the latest applications of aptamer-based functional probes in the fields of bioanalysis and biomedicine.

Nucleic acid aptamer-based methods for diagnosis of infections

“…First, it has been reported that natural nucleic acids do not possess the full spectrum of chemical functional groups and conformational space needed to yield high-quality aptamers for many proteomic targets. To solve this problem, a number of methods (e.g., Hi-Fi SELEX (Ouellet et al, 2015), array-based strategies (Cho et al, 2015) and multiparameter particle display strategies ) have been developed, which have led to greater selection efficiencies (Zhang et al, 2016). In this light, chemical methods for DNA synthesis have enabled the incorporation of special functional groups onto oligonucleotides and have led to a significant advancement in the number of diverse aptamers that are available (Kimoto et al, 2013).…”

Deciphering the killer‐cell immunoglobulin‐like receptor system at super‐resolution for natural killer and T‐cell biology

“…Although antibody combinations can help to decipher these activating KIRs,187, 192, 201 they do not allow analysis at single KIR level because of antibody cross‐reactivity. Aptamers, short single‐stranded nucleic acid oligomers that bind to a specific target molecule, with their unique features of high binding affinity and specificity, could offer a useful alternative to antibodies in discriminating subtly different forms of KIR 209. Improving KIR repertoire analysis will contribute to our understanding of clinical situations where KIR have a proven or suspected role such as antiviral immune response, transplantation, autoimmunity and reproduction.…”

Production of polycaprolactone nanoparticles with hydrodynamic diameters below 100 nm

“…One approach is the utilization of drug delivery systems, where drugs are combined with carriers like micelles, liposomes, or nanoparticles to transport the drug to the target tissue . These carrier systems usually have sizes between 10 and 200 nm . The determined size limit of particles for internalization into cells via receptor‐mediated endocytosis was 200 nm, consequently the size of carriers should not exceed this size if particles are to be internalized by this uptake route .…”

“…The determined size limit of particles for internalization into cells via receptor‐mediated endocytosis was 200 nm, consequently the size of carriers should not exceed this size if particles are to be internalized by this uptake route . Furthermore, the size between 10 and 200 nm limits the penetration through the endothelial cells in healthy vasculature, but the leaky vasculature in solid tumors enables enrichment of particles in the tumor tissue . This effect is called enhanced permeability and retention effect .…”

“…These sizes are not suitable for the use in drug delivery systems especially if targeting ligands should be added that can further increase nanoparticle size . By introducing a targeting ligand to a drug delivery system, nanocarriers can specifically bind to target cells, which consequently internalize the particles and therefore allow a drug release inside the cells . Aptamers are one group of affinity ligands, which can be used for such targeting purpose .…”