Electrochemical deposition of Ni–TiN nanocomposite coatings and the effect of sodium dodecyl sulphate surfactant on the coating properties

Ni–TiN nanocomposite coatings were prepared by using electrochemical deposition in a Watt’s bath containing TiN particles to increase the hardness of Ni. The effects of deposition current density, electrolyte agitation speed and the number of particles in the solution on the amount of incorporated particles in the coating process were investigated. The optimum deposition current density of 4 A dm^?2 and agitation speed of 450 rpm were obtained. The effect of sodium dodecyl sulphate (SDS) anionic surfactant on the amount of particles in the coatings was investigated. It was observed that the maximum amount of incorporated particles, with a value of 7.5% by volume, was created in the current density of 4 A dm^?2, stirring rate of 450 rpm, 30 g l^?1 TiN particles and in the presence of 0.6 g l^?1 SDS anionic surfactant.     

Preparation and electrochemical application of a new biosensor based on plant tissue/polypyrrole for determination of acetaminophen

Banana tissue containing polyphenol oxidase was incorporated into polypyrrole matrix to make a biosensor for the analysis of acetaminophen (ACT). The electrocatalytic behaviour of oxidized acetaminophen was studied at the surface of the biosensor, using various electrochemical methods. The advantages of this biosensor for the determination of acetaminophen are excellent catalytic activity, good detection limit and high exchange current density. The electrochemical and structural properties of the electrode were assessed using cyclic voltammetry, differential voltammetry, chronoamperometric techniques. The analytical properties (sensitivity, I _p ) of this biosensor increased with plant tissue loading. Also this new biosensor was successfully applied for determination of acetaminophen in biologic samples.