Non-SELEX isolation of DNA aptamers for the homogeneous-phase fluorescence anisotropy sensing of tau Proteins

Abstract

A new DNA aptamer against Alzheimer's disease biomarkers (t-441, t-381, t-352 and t-383) was selected.Non-SELEX was used to isolate highaffinity DNA sequences in one working day.The affinity constants were comparable with those previously reported for CE-SELEX-selected aptamers.A fluorescence anisotropy sensing platform allowed the detection of the four t-isoforms with a nM detection limit..

Development of a Label-Free Electrochemical Aptasensor for the Detection of Tau381 and its Preliminary Application in AD and Non-AD Patients’ Sera

“…Aptamers can be invoked as recognition elements superior to antibodies because of their chemical stability, ease to modify, high affinity, specificity, and fixation density on the electrodes. Krylova et al [9] used affinity-mediated non-equilibrium capillary electrophoresis of equilibrium mixtures to study the interaction of tau381 and aptamers, and the dissociation rate constant K d was 0.19 ± 0.01 μM; moreover, the K d value found by Lisi et al [10] was 116 ± 6 nM. Thus, aptamers are particularly attractive in the field of clinical testing and electrochemical sensing [11,12].…”

“…Thus, aptamers are particularly attractive in the field of clinical testing and electrochemical sensing [11,12]. Various biosensor transductions are displayed in Table 1, fluorescence [10], electrochemistry [13,14,15,16], and surface plasmon resonance (SPR) [17,18,19], have been developed for tau biosensors. Until now, the electrochemical transduction was associated with anti-tau antibody as a recognition element.…”

Biosensing extracellular vesicles: contribution of biomolecules in affinity-based methods for detection and isolation

“…Dealing with this challenge, non-SELEX aptamer selection has been developed to obtain new probes in one working day. 115 In parallel, the engineering of a novel class of proteins based on single-domain antibody fragments (nanobodies) also offers promising novel probes in the coming years. Their specificity is equal to the antibody's in addition to be being smaller in size, more chemically stable, and therefore easier to handle.…”

Screening of aptamers and their potential application in targeted diagnosis and therapy of liver cancer

“…Blended SELEX[29], complex targeting SELEX[30], expression cassette SELEX[31], and toggle SELEX[32] can improve the universality of aptamers. In addition, automated SELEX[33], non-SELEX[34], and FluMag SELEX[35] can shorten the screening cycle. Methods for combining different pools, such as tailored SELEX[36] and genomic SELEX[37], can increase the likelihood of screening for aptamers of interest.…”