What is aptamer technology?
Aptamers are short, single-stranded DNA, RNA, or synthetic XNA molecules that can be developed with high affinity and specificity to interact with any desired targets. They have been widely used in facilitating discoveries in basic research, ensuring food safety and monitoring the environment.
Why is an aptamer a practical strategy for clinical application?
Aptamers are a special class of nucleic acid molecules that are beginning to be investigated for clinical use. With advances in targeted-therapy, imaging, and nanotechnology, aptamers are readily considered as potential targeting ligands because of their chemical synthesis and ease of modification for conjugation.
What are aptamers and how are they used for the detection of DNA damage?
Since their discovery, aptamers have been compared to antibodies due to their similar ability to bind to specific targets. As a result, aptamers can be selected against DNA-damaging toxins or the resulting lethal DNA adducts that are challenging for antibody generation.
What is Selex what can it be used for?
Systematic Evolution of Ligands by EXponential Enrichment (SELEX) is a common method currently used for isolating high-affinity single-stranded (ss) DNAs or RNAs from a large library with random sequences [1,2,3].
What is the difference between aptamer and antibody?
They are in general more stable than antibodies, and have a longer shelf life. Aptamers are produced through a simple and inexpensive process and the time required to generate aptamers is comparatively short. Unlike antibodies, aptamers do not need animals or an immune response for their production.
How are aptamers designed?
Aptamers are usually created by selecting them from a large random sequence pool, but natural aptamers also exist in riboswitches. Aptamers can be used for both basic research and clinical purposes as macromolecular drugs. Aptamers can be combined with ribozymes to self-cleave in the presence of their target molecule.
How are aptamers administered?
There is limited published information concerning the toxicological properties of aptamer therapeutics because so far there is only one approved aptamer drug (pegaptanib), which is administered in small doses by intravitreal injection.
How are aptamers synthesized?
Ease of synthesis: Aptamers can be synthesized using solid phase oligonucleotide synthesis, whereas antibodies have to be obtained using less efficient biochemical or biological methods. This is particularly important if the synthesis is to be scaled up.
What is the SELEX process?
Specifically, SELEX process includes (1) the incubation of target molecules with the random sequence pools, (2) and the subsequent separation of unbound oligonucleotides and the elution of bound oligonucleotides, (3) then PCR amplification of bound aptamers.
Why are aptamers better than antibodies?
Aptamers offer significant advantages over antibodies [8]. They are in general more stable than antibodies, and have a longer shelf life. The in vitro selection process allows aptamers to be generated against otherwise toxic compounds that would kill the animal in antibody production.
What are the recent advances in aptamer technology?
In recent years, the aptamer technology saw a significant upturn as novel developments in chemical synthesis, technical equipment, and analysis methods became available for enhancing the properties of aptamers and the efficiency of their development.
How is aptamer selection used in protein isolation?
The primer-free DNA aptamer selection 32 was used to isolate aptamers against the target protein S100B with K D s in the range of 10 −7 to 10 −8 mol/l and employs endonucleases cleaving of the doubled stranded DNA template.
Which is the most efficient aptamer separation method?
Aptamers with low nmol/l dissociation constants for IgE could be identified already after one selection cycle, indicating that μFFE is a very efficient separation method. 47 SELEX is an in vitro selection process, which is conducted by applying very defined protocols and quite robust enzymatic amplification.
How are nucleic acids selected in RNA aptamer?
The remaining nucleic acids are amplified by PCR in DNA aptamer selections or RT-PCR and RNA transcription in RNA aptamer selections. This selection cycle has to be repeated for 8–16 times to enrich the high affinity binding nucleic acids which are identified by cloning and Sanger sequencing.