Electrochemical Immunosensing Platform for the Determination of the 20S Proteasome Using an Aminophenylboronic/Poly-indole-6-carboxylic Acid-Modified Electrode

Abstract

The first electrochemical immunosensor for the determination of the 20S proteasome (P20S) was developed, entailing the immobilization of an antibody on an aminophenylboronic/poly-indole-6carboxylic acid-modified electrode. The proposed electrochemical bioplatform is a simple and feasible analytical tool applicable for the determination of P20S in human plasma, considering its high clinical and biological relevance. Cyclic voltammetry, electrochemical impedance spectroscopy, and square wave voltammetry (SWV) were used to determine the optimal step-by-step process to obtain the electrochemical immunosensor. The interaction of P20S with the recognition layer of the immobilized antibody on the nanostructured surface took place by incubating the electrode in a P20S solution at 20 °C for 2 h. Using SWV as an electro-analytical technique, this immunosensor can quantify P20S. The current was linear with the P20S concentration within two dynamic concentration ranges from 20.0 to 80.0 and 80.0 to 200.0 ng•mL −1 (r 2 = 0.992 and 0.98, respectively) with a limit of detection and quantification of 6 and 18 ng•mL −1 , respectively. Moreover, the immunosensor showed considerable repeatability and reproducibility, when the determination was done in human serum, which confirms that it is a promising alternative for direct detection of P20S in biological fluids with minimal interference.

Immobilized Antibodies on Mercaptophenylboronic Acid Monolayers for Dual-Strategy Detection of 20S Proteasome

“…A comparison was also performed in relation to the only electrochemical immunosensor described in the scientific literature whose detection principle is based on the inhibition of the polymer electroactivity. Although this type of immunosensor allowed very low detection limits [ 18 ], its limited dynamic range makes difficult the precise detection of 20S in a relevant biological sample without intensive sample pretreatment.…”

“…The present study reports the development and application of an immunosensor for the electrochemical detection of 20S proteasome (20S). To our knowledge, only one electrochemical immunosensor for 20S has been reported previously, based on an electroactive polymer responsible for the detection principle, with the decrease in the polymer peak currents being correlated to the linkage of 20S to an immobilized 20S antibody [ 18 ].…”

Capacitors Based on Polypyrrole Nanowire Electrodeposits

“…In recent decades, conducting polymers (CP) have occupied an important place in the study of new types of materials, due to their different properties, which has led to the development of a wide range of electronic devices, such as electrochemical sensors [1,2], OLED (organic light emitting diodes) [3], photovoltaic cells [4,5], rechargeable batteries [6][7][8] and capacitors [9,10]. In the case of these last devices, conducting polymers stand out in comparison with inorganic compounds due to their high specific capacity, which can reach up to 2000 F g −1 in the case of polyaniline in sulfuric acid [11].…”