Detection of multiple antibodies using nanopores - Database & Sql Blog Articles

Researchers at the University of Cambridge in the United Kingdom recently published a report on "Nature Nanotechnology" that they can use quartz nanopores to identify dumbbell-shaped DNA structures for antibody detection.



Nicholas Bell and Ulrich Keyser used the principle of DNA origami to design a structure that carries a unique digital barcode consisting of multiple dumbbell-shaped DNA hairpin structures. With the nanopore, they are able to read the three-digit barcode with 94% accuracy. They then incorporate antigen into the DNA strand and can detect up to four antibodies at a time.



In this study, researchers used DNA vectors to selectively drive proteins through the nanopore. Keyser is responsible for controlling the size of the nanopore. They created a double-stranded DNA structure in which one chain has a dumbbell-shaped hairpin structure.



First, researchers need to create a single digital bit that can be read by the nanopore. In order to distinguish them from the background signal, they found that it is necessary to incorporate multiple hairpin structures on the double-stranded DNA backbone. The fewer the hairpin structure, the more bits in each DNA strand, and the more hairpin structures, the stronger the signal and the higher the accuracy. Between coding more data and getting stronger signals, the researchers weighed repeatedly and chose 11 hairpins per person.



Then they built a three-digit digital system that formed eight unique barcodes. They then incorporated these barcodes into the DNA carrier molecule that presented the antigen and used it to bind the antibody. "The presence of antibodies does not significantly affect the kinetics of DNA," the authors write, which means that barcodes can be used to read the presence of antibodies.



To prove this, Bell and Keyser created structures that present biotin, BrdU, puromycin, and successfully detected antibodies at concentrations as low as 10 nanomolar. They believe that this technology is expected to be applied to scientific research and clinical diagnosis.



Nanopore sequencers have been used in DNA detection in the past, but there have been many recent advances in protein detection. Earlier, a research team at the University of Pennsylvania modified the opening of the nanopore to accommodate larger proteins. In this way, they distinguished the monomeric and dimeric structures of the GCN4-p1 protein.