Adsorption and Interaction of Bovine Serum Albumin and Pluronic P103 Triblock Copolymer on a Gold Electrode: Double-Layer Capacitance Measurements

Abstract

The interactions of proteins and other molecules and their adsorption onto substrates is a fascinating topic that has been applied to surface technologies, biosensors, corrosion studies, biotechnologies, and other fields. The success of these applications requires a previous characterization using some analytical techniques that, ordinarily, are not electrochemical. This work proposes analyzing the variation of the double-layer capacitance obtained through impedance electrochemical spectroscopy as an alternative strategy to show evidence of the interactions between proteins and triblock copolymers. The proposal is supported through the study of the interaction and adsorption of bovine serum albumin (BSA) and a commercial triblock copolymer (P103) in phosphate buffer on a gold electrode. The double-layer capacitance and the apparent interface thickness vs polarization potential curves as well as the potential of zero charge for pure P103 (0.6 wt %, corresponding to 6 g L –1 ), pure BSA (3 mg mL –1 ), and P103-BSA solutions (0.6 wt % and 3 mg mL –1 , respectively) are sensitive enough to show not only the interaction and the adsorption of the species but also the polarization potential where these interactions are taking place. A qualitative and quantitative analysis concerning the double-layer capacitance behavior is given. The significance and impact of this work is also presented.

A Comparison between Silver Nanosquare Arrays and Silver Thin-Films as a Blood Cancer Prognosis Monitoring Electrode Design Using Optical and Electrochemical Characterization

“…The presence of BSA may hinder the oxidation reaction of the solution due to BSA decreasing the balance of the solution. Furthermore, BSA also has blocking effect on the surface of electrodes and is able to experience adsorption on the surface of metal electrodes [20]. Therefore, the presence of higher serum albumin within the blood may shift the peak of the oxidation and reduction current to a smaller value.…”

“…A nanostructure is a form of electrode that has the potential to become a biosensor due to its high sensitivity and accuracy in detecting cancer biomarkers and its nature attractiveness with molecules [19]. Gold (Au) is commonly used as a biosensor [20][21][22]. However, Ag is also a good candidate for biosensors.…”

Synthesis and characterization of a nanostructure conductive copolymer based on polyaniline and polylactic acid as an effective substrate in proteins impedimetric biosensing

“…15,16 Biomolecules such as protein and cells can attach to the surface of amphiphilic block copolymer, and due to the ability of the amphiphilic copolymer to form micelles, they can be used in the construction of biosensors. 17 Nowadays, for the development of new biosensors, many studies have been conducted on the interaction of proteins with polymer surfaces. One of these proteins is BSA, which is commonly used as a model protein for electrochemical sensor studies.…”

Ionic Strength Effect in the Equilibrium and Rheological Behavior of an Amphiphilic Triblock Copolymer at the Air/Solution Interface

“…One of the most fascinating features of Pluronics is their capacity to reduce protein adsorption on solid surfaces. This has significant implications, notably in biomedical applications where avoiding undesired protein adsorption (biofouling) is critical for implantable devices, biosensors, and drug delivery systems [12,13].…”