The Adsorption Study Of Skimmed Milk At Electrode By Electrochemical And QCM

The study on the interfacial adsorption behavior between milk and the surface of electrode can provide theoretical basis for electronic tongue. In the study, interfacial double layer capacitance information of Pt electrode and Au electrode was explored by electrochemical method and the law of adsorption of skimmed milk on the surface of Au electrode on different conditions was researched with quartz crystal microbalance.In low concentration of skimmed milk, the adsorption behavior of milk on the Pt and Au electrode was characterized by cyclic voltammetry and electrochemical impedance spectroscopy. Without adding skimmed milk in, the surface of the electrode was mainly involves diffusion, and kinetically controlled with skimmed milk, respectively. Open circuit potential and differential capacitance were used to study different concentration of skimmed milk dispersion adsorption property on the surface of Pt and Au electrode, the results show that adsorption rate of skimmed milk on the surface of two electrodes were quickly increase at first and gradually slow down and then become balanced. Within a certain concentration range, skimmed milk dispersion was monomolecular layer adsorbed on the surface of the two electrodes, and in line with the Langmuir adsorption isotherm equation.The effects of concentration, pH and ionic strength on the adsorption behavior of skimmed milk dispersion on gold crystal surface were researched in different adsorption conditions by quartz crystal microbalance. The results were as follows: skimmed milk on the adsorption of gold crystal surface gradually reached saturation with the increase of skimmed milk concentration; in different pH buffer solution, the adsorption quantity of milk on the surface of electrode is different, in the pH of 5 reached the maximum adsorption; at the same concentration and p H, adsorption capacity increase firstly and then decreased with the increase of ionic strength.