This article presents an electrochemical impedance study on the detection of Alkaline Phosphatase (ALP) in phosphate buffer saline (PBS) solution by using anti-ALP functionalized Si nanowires (SiNWs). Electrochemical impedance was measured using a three-electrode cell where the working electrode was a very dense and highly disordered array of Si NWs, e.g. SiNW-forest. This array was grown using plasma enhanced chemical vapor deposition (PECVD) at 350 degrees C. The NW surface was modified by immobilizing the anti-ALP. A very efficient detection of very low ALP concentrations in PBS solution, ranging from 0.03 U/L to 0.3 U/L (1 nM-10 nM respectively), as well as a high selectivity due to the antibody/antigen interaction were demonstrated. The remarkable sensitivity and selectivity achieved through the combination of SiNW-forest combined electrochemical impedance spectroscopy suggest an effective strategy for real time and quantitative sensing of ALP. (C) 2017 Elsevier B.V. All rights reserved.
Alkaline phosphatase detection using electrochemical impedance of anti-alkaline phosphatase antibody (Ab354) functionalized silicon-nanowire-forest in phosphate buffer solution
Convertino Annalisa;
2018
Abstract
This article presents an electrochemical impedance study on the detection of Alkaline Phosphatase (ALP) in phosphate buffer saline (PBS) solution by using anti-ALP functionalized Si nanowires (SiNWs). Electrochemical impedance was measured using a three-electrode cell where the working electrode was a very dense and highly disordered array of Si NWs, e.g. SiNW-forest. This array was grown using plasma enhanced chemical vapor deposition (PECVD) at 350 degrees C. The NW surface was modified by immobilizing the anti-ALP. A very efficient detection of very low ALP concentrations in PBS solution, ranging from 0.03 U/L to 0.3 U/L (1 nM-10 nM respectively), as well as a high selectivity due to the antibody/antigen interaction were demonstrated. The remarkable sensitivity and selectivity achieved through the combination of SiNW-forest combined electrochemical impedance spectroscopy suggest an effective strategy for real time and quantitative sensing of ALP. (C) 2017 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.