Aptamer-Based Targeted Drug Delivery Systems: Current Potential and Challenges

Abstract

: Aptamers are single-stranded DNA or RNA with 20-100 nucleotides in length that can specifically bind to target molecules via formed three-dimensional structures. These innovative targeting molecules have attracted an increasing interest in the biomedical field. Compared to traditional protein antibodies, aptamers have several advantages, such as small size, high binding affinity, specificity, good biocompatibility, high stability and low immunogenicity, which all contribute to their wide application in the biomedical field. Aptamers can bind to the receptors on the cell membrane and mediate themselves or conjugated nanoparticles to enter into cells. Therefore, aptamers can be served as ideal targeting ligands for drug delivery. Since their excellent properties, different aptamer-mediated drug delivery systems had been developed for cancer therapy. This review provides a brief overview of recent advances in drug delivery systems based on aptamers. The advantages, challenges and future prospectives are also discussed.

Metal-organic frameworks for virus detection

“…Additionally, the detection performance and safety of MOF-based biosensing need to be further verified in vivo due to the complex in vivo environment, and the long-term biological toxicity of metal ion in MOF need to be further evaluated in vivo ( Chen et al, 2019 ), some biocompatible metal ions, such as Fe 2+ /Fe 3+ , Ni 3+ , Zr 4+ , Mn 2+ , Mg 2+ , Ca 2+ , Zn 2+ , or biomaterials, such as liposomal ( Dunne et al, 2019 ), bioconjugates ( Malfanti et al, 2019 ), and green synthetic routes should also be considered. The functional modification of MOFs with target ligands, such as aptamers ( Cai et al, 2018 ; He et al 2020a , 2020b ; Liu et al 2014a , 2015 ; Xiong et al, 2019 ) would endow the MOFs with more functionalities, with detection performances even better than the biosensor platforms based on graphene oxide ( Du et al, 2020 ; Liu et al, 2014b ).…”

Multivalent weak interactions enhance selectivity of interparticle binding

“…These principles are also exploited in nanomedicine to develop nanoparticles that target specific cell types in order to improve diagnosis and treatment ( 6 – 8 ). The targeting relies on identifying membrane receptor signatures that are unique to the targeted cell.…”

Tumor microenvironment responsive drug delivery systems

“…The strategy is expected to realize selective recognition of appropriate receptors or antigens overexpressed by cancer cells or tumor vasculature, thus promoting the cellular uptake of the loaded cargo via receptor-mediated endocytosis. Numerous moieties targeting to tumor cells have been exploited in DDSs design, such as proteins (transferrin) [29] , vitamins (FA) [33] , peptides (arginine-glycine-aspartic acid and AG73 peptide) [34] , nucleic acids (aptamer) [35] , [36] , [37] , and some other molecules (hyaluronic acid) [38] . Some moieties allowing specific mitochondria targeting are also developed including triphenylphosphonium, dequalinium, mitochondrial penetrating peptides and mitochondrial protein import machinery [39] .…”