1. INTRODUCTION Electrochemical Impedance Spectroscopy is an effective method of analyzing the intricate electrical resistance of a process and it is sensitive to surface phenomena and changes in the bulk properties. Thus it plays a major role in electrochemical research. It has been diligently used for the interpretation of corrosion mechanisms and in the characterisation of charge transport over the membrane. In the area of biosensors, it is especially appropriate for the detection of binding events on the transducer surface. In this report a short prologue to the measuring principles of electrochemical impedance spectroscopy could be furnished, followed by an outline of the utilization of the procedure in the discipline of biosensors.
…show more content…
[1] [2] It is based on the interaction of an external field with the electric dipole moment of the sample which is represented as permittivity. [3], [4]. This method measures the impedance of a process over the different range of frequencies. The data obtained by this method is plotted and graphical data is obtained using a Bode plot or a Nyquist plot. In electrochemical impedance spectroscopy four elements are used to explain the impedance behavior: ohmic resistance, constant phase element, Warburg impedance and capacitance. To characterize a biological materials like antigen or antibodies, electrodes should be introduces into the system, thus it forms an electrochemical …show more content…
This is cleaned with water and ethanol followed by etching with 10:1 HF to remove the native oxides. This is directly dipped into 10% 10-undecanoic acid in deaerated toluene for 19h, with exposure to 352 nm ultraviolet light for photoactivated alkene insertion into Si-H bonds, which creates a carboxylate-terminated surface. The Au electrode was cleaned and immersed into 1mM 11-Mercaptoundecanoic acid and 50mM phosphate buffer for about 17h to form a carboxylate-terminated self-assembled monolayer followed by the activation carboxylate groups on Si and Au electrode in 75mM N-(3-(Dimethylamino)propyl-N’-(ethylcarbodiimide hydrochloride) and 15mM N-hydroxysulfosuccinimide sodium salt in 50mM buffer solution for about 1h. The antibody coated electrodes were created by immersing for 1h into a solution of 50µg/mL antibody and 50mM Phosphate-buffered saline at pH 7.3, which results in forming of amide bonds to amine groups on the protein surface, and then it is immersed into 0.1% BSA for 1h in order to reduce the nonspecific
[1] [2] It is based on the interaction of an external field with the electric dipole moment of the sample which is represented as permittivity. [3], [4]. This method measures the impedance of a process over the different range of frequencies. The data obtained by this method is plotted and graphical data is obtained using a Bode plot or a Nyquist plot. In electrochemical impedance spectroscopy four elements are used to explain the impedance behavior: ohmic resistance, constant phase element, Warburg impedance and capacitance. To characterize a biological materials like antigen or antibodies, electrodes should be introduces into the system, thus it forms an electrochemical …show more content…
This is cleaned with water and ethanol followed by etching with 10:1 HF to remove the native oxides. This is directly dipped into 10% 10-undecanoic acid in deaerated toluene for 19h, with exposure to 352 nm ultraviolet light for photoactivated alkene insertion into Si-H bonds, which creates a carboxylate-terminated surface. The Au electrode was cleaned and immersed into 1mM 11-Mercaptoundecanoic acid and 50mM phosphate buffer for about 17h to form a carboxylate-terminated self-assembled monolayer followed by the activation carboxylate groups on Si and Au electrode in 75mM N-(3-(Dimethylamino)propyl-N’-(ethylcarbodiimide hydrochloride) and 15mM N-hydroxysulfosuccinimide sodium salt in 50mM buffer solution for about 1h. The antibody coated electrodes were created by immersing for 1h into a solution of 50µg/mL antibody and 50mM Phosphate-buffered saline at pH 7.3, which results in forming of amide bonds to amine groups on the protein surface, and then it is immersed into 0.1% BSA for 1h in order to reduce the nonspecific