Quantifying Nanomolar Protein Concentrations Using Designed DNA Carriers and Solid-State Nanopores.
Designed "DNA carriers" have been proposed as a new method for nanopore based specific protein detection. In this system, target protein molecules bind to a long DNA strand at a defined position creating a second level transient current drop against the background DNA translocation. Here, we demonstrate the ability of this system to quantify protein concentrations in the nanomolar range. After incubation with target protein at different concentrations, the fraction of DNA translocations showing a secondary current spike allows for the quantification of the corresponding protein concentration. For our proof-of-principle experiments we use two standard binding systems, biotin-streptavidin and digoxigenin-antidigoxigenin, that allow for measurements of the concentration down to the low nanomolar range. The results demonstrate the potential for a novel quantitative and specific protein detection scheme using the DNA carrier method.
Cavendish Laboratory, University of Cambridge , JJ Thomson Ave, Cambridge, CB3 0HE, United Kingdom.
Jinglin
J
Kong
Cavendish Laboratory, University of Cambridge , JJ Thomson Ave, Cambridge, CB3 0HE, United Kingdom.
Nicholas A W
NA
Bell
Cavendish Laboratory, University of Cambridge , JJ Thomson Ave, Cambridge, CB3 0HE, United Kingdom.
Ulrich F
UF
Keyser
D000906:Antibodies / Q000737:chemistry; D001426:Bacterial Proteins / Q000032:analysis; D015374:Biosensing Techniques; D001710:Biotin / Q000031:analogs & derivatives / Q000032:analysis; D004247:DNA / Q000737:chemistry*; D004076:Digoxigenin / Q000032:analysis / Q000276:immunology; D004337:Drug Carriers / Q000737:chemistry*; D057230:Limit of Detection; D058608:Nanopores; D011506:Proteins / Q000032:analysis*
D000906:Antibodies; D001426:Bacterial Proteins; D004337:Drug Carriers; D011506:Proteins; C066114:biotin-streptavidin complex; D001710:Biotin; D004247:DNA; D004076:Digoxigenin
DNA; Nanopore; biosensing; concentrations; proteins; quantifying