6533b7d3fe1ef96bd1260bc0

RESEARCH PRODUCT

Label-Free Pyrophosphate Recognition with Functionalized Asymmetric Nanopores

Mubarak AliWolfgang EnsingerSalvador MafeIshtiaq AhmedChristof M. NiemeyerSaima NasirPatricio Ramirez

subject

Adenosine monophosphatechemistry.chemical_elementNanotechnology02 engineering and technologyZincPicolinic acid010402 general chemistry01 natural sciencesPyrophosphateBiomaterialsNanoporeschemistry.chemical_compoundPolymer chemistryGeneral Materials ScienceAminesPicolinic AcidsStaining and LabelingGeneral Chemistry021001 nanoscience & nanotechnologyPhosphate0104 chemical sciencesDiphosphatesAdenosine diphosphatechemistryFISICA APLICADASurface modificationAmine gas treating0210 nano-technologyBiotechnology

description

[EN] The label¿free detection of pyrophosphate (PPi) anions with a nanofluidic sensing device based on asymmetric nanopores is demonstrated. The pore surface is functionalized with zinc complexes based on two di(2¿picolyl)amine [bis(DPA)] moieties using carbodiimide coupling chemistry. The complexation of zinc (Zn2+) ion is achieved by exposing the modified pore to a solution of zinc chloride to form bis(Zn2+¿DPA) complexes. The chemical functionalization is demonstrated by recording the changes in the observed current¿voltage (I¿V) curves before and after pore modification. The bis(Zn2+¿DPA) complexes on the pore walls serve as recognition sites for pyrophosphate anion. The experimental results show that the proposed nanofluidic sensor has the ability to sense picomolar concentrations of PPi anion in the surrounding environment. On the contrary, it does not respond to other phosphate anions, including monohydrogen phosphate, dihydrogen phosphate, adenosine monophosphate, adenosine diphosphate, and adenosine triphosphate. The experimental results are described theoretically by using a model based on the Poisson¿Nernst¿Planck equations.

yearjournalcountryeditionlanguage
2016-01-01Small
https://doi.org/10.1002/smll.201600160