Real time protein recognition in a liquid-gated carbon nanotube field-effect transistor modified with aptamers.
The combination of optimized and passivated Field Effect Transistors (FETs) based on carbon nanotubes (CNTs) together with the appropriate choice and immobilization strategy of aptamer receptors and buffer concentration have allowed the highly sensitive and real time biorecognition of proteins in a liquid-gated configuration. Specifically we have followed the biorecognition process of thrombin by its specific aptamer. The aptamer modified device is sensitive enough to capture a change in the electronic detection mechanism, one operating at low protein concentrations and the other in a higher target concentration range. The high sensitivity of the device is also sustained by the very low detection limits achieved (20 pM) and their high selectivity when other target proteins are used. Moreover, the experimental results have allowed us to quantify the equilibrium constant of the protein-aptamer binding and confirm its high affinity by using the Langmuir equation.
Grup de Sensors i Biosensors, Departament de Química, Facultat de Ciències, Edifici C-nord, UniversitatAutònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain.
Mercè
M
Pacios
Iñigo
I
Martin-Fernandez
Xavier
X
Borrisé
Manel
M
del Valle
Jordi
J
Bartrolí
Emilio
E
Lora-Tamayo
Philippe
P
Godignon
Francesc
F
Pérez-Murano
María José
MJ
Esplandiu
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D009211:Myoglobin / Q000737:chemistry / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010196:Pancreatic Elastase / Q000737:chemistry / Q000378:metabolism; D013917:Thrombin / Q000737:chemistry* / Q000378:metabolism; D014173:Transistors, Electronic
D052157:Aptamers, Nucleotide; D009211:Myoglobin; D037742:Nanotubes, Carbon; D010196:Pancreatic Elastase; D013917:Thrombin