Flow Cytometric Bead Sandwich Assay Based on a Split Aptamer

Abstract

A few aptamers still bind their targets after being split into two moieties. Split aptamers have shown great potential in the development of aptameric sensors. However, only a few split aptamers have been generated because of lack of knowledge on the binding structure of their parent aptamers. Here, we report the design of a new split aptamer and a flow cytometric bead sandwich assay using a split aptamer instead of double antibodies. Through DMS footprinting and mutation assay, we figured out the target-binding moiety and the structure-stabilizing moiety of the l-selectin aptamer, Sgc-3b. By separating the duplex strand in the structure-stabilizing moiety, we obtained a split aptamer that bound l-selectin. After optimization of one part of the split sequence to eliminate the nonspecific binding of the split sequence pair, we developed a split-aptamer-based cytometric bead assay (SACBA) for the detection of soluble l-selectin. SACBA showed good sensitivity and selectivity to l-selectin and was successfully applied for the detection of spiked l-selectin in the human serum. The strategies for generating split aptamers and designing the split-aptamer-based sandwich assay are simple and efficient and show good practicability in aptamer engineering.

Oligonucleotide aptamers for pathogen detection and infectious disease control

“…For structure-switching aptamers, some improvements have been developed based on fluorescence resonance energy transfer (FRET). Shen et al split a DNA aptamer into two parts for target detection 38 . One part was labeled with biotin and the other with a fluorophore.…”

Can Polymer Solar Cells Open the Path to Sustainable and Efficient Photovoltaic Windows Fabrication?

“…Although the PTB7-Th : PC 71 [35] Shen et al recently managed to considerably increase that value ( Figure 5(b)). [36] The authors employ photonic crystals acting as Bragg reflectors to balance the transmitted colors and increase the CRI of their reference device (CRI = 91) up to 95 while maintaining an AVT of 20 %. However, starting with active layers that homogeneously absorb throughout the visible will remove the necessity for additional photonic crystal-like structures engineering.…”

“…On the other hand, including photonic crystals within the device architecture for light manipulation can enhance the PSC performances but generally leads to a reduction in transmitted light. [36,42,43] To ensure that PSC-based PWs are one day commercialized, other aspects have to be taken into account such as the production cost and the sustainability of the fabrication process. [44] In Section 3, I will review some techniques for eco-friendly and sustainable active layer fabrication.…”

“…Adapted with permission from, [35] Copyright 2017, Elsevier B.V. (b) CIE coordinates, photograph and J-V curves of PTB7-Th : PC 71 BM PSCs employing photonic crystals as Bragg reflectors. Adapted with permission from, [36] Copyright 2018, American Chemical Society. [37] Copyright 2015, American Chemical Society .…”

A Novel Ratiometric Electrochemical Biosensor Based on a Split Aptamer for the Detection of Dopamine with Logic Gate Operations

“…Li et al constructed a ratiometric electrochemical sensor based on a mismatched catalytic hairpin assembly for the detection of microRNA . In addition, recent work demonstrated that the signal background could be reduced by splitting the aptamer . Zheng et al developed a DNA nanoprobe for ATP based on FRET between the strands of a split aptamer .…”