Protein immobilization on electrodes is a key concept in exploiting enzymatic processes for bioelectronic devices. For optimum performance, an in-depth understanding of the enzyme-surface interactions is required. Here, we introduce an integral approach of experimental and theoretical methods that provides detailed insights into the adsorption of an oxygen-tolerant [NiFe] hydrogenase on a bioco...

The inhibitory effect of nine phenylcarbamates with various substituents was studied. For this purpose, electrochemical sensors were applied under two different conditions: if an enzyme was present in the solution or if the enzyme was immobilized onto the electrode surface. In both cases, 3-[(ethoxycarbonyl)amino]phenyl (4-chlorophenyl)carbamate was found as the most effective inhibitor for but...

Hydrogen peroxide sensors where horseradish peroxidase (HRP) is incorporated into pyrrole/3-alkylsulfonate pyrrole copolymer films deposited on an SnO2 electrode (HRP/Py-PS electrode) were investigated with regard to the effects of the fabrication parameters (electropolymerization charge, deposition current density, and electrodeposition solution pH) on the amount of surface-immobilized enzyme ...

The aim of this work is to develop a method for ascorbic acid determination in some fruit juices, by using an ascorbate oxidase-based amperometric enzyme electrode. The enzyme was immobilized on a nylon (Biodyne A) membrane by glutaraldehyde linking. The enzyme-membrane was consecutively attached to the polyethylene membrane of a Clark oxygen electrode, which functioned as transducer. The analy...

The simplest transducer in the development of potentiometric biosensors is the glass pH electrode. Glucose oxidase immobilization was achieved using cellophane [1], nylon [1-6] or nitrocellulose [5,7] membranes that are subsequently fixed on the sensitive bulb of the pH electrode that senses the pH diminution, as a result of the biocatalytical reaction occurring in the enzyme layer (glucose oxi...

We present a novel and efficient nanoporous microfluidic biochip consisting of a functionalized chitosan/anatase titanium dioxide nanoparticles (antTiO2-CH) electrode integrated in a polydimethylsiloxane (PDMS) microchannel assembly. The electrode surface can be enzyme functionalized depending on the application. We studied in detail cholesterol sensing using the cholesterol esterase (ChEt) and...

A novel biosensor for l-ascorbic acid determination in different beverages was elaborated. The ascorbate oxidase enzyme (AAO) from Cucurbita sp., EC 1.10.3.3, was immobilized on a screen-printed carbon electrode with poly(ethylene glycol) (400) diglycidyl ether (PEGDGE) as a crosslinking agent. The standards and samples were measured first with a blank electrode. An inert protein, bovine serum ...

A DNA/chitosan-Fe₃O₄ magnetic nanoparticle bio-complex film was constructed for the immobilization of horseradish peroxidase (HRP) on a glassy carbon electrode. HRP was simply mixed with DNA, chitosan and Fe₃O₄ nanoparticles, and then applied to the electrode surface to form an enzyme-incorporated polyion complex film. Scanning electron microscopy (SEM) was used to study the surface features of...