In this paper we present results of detecting

In this paper, we present results of detecting mercury at rotating silver electrode (RSE) in a mixture of 0.1molL−1 HCl and 0.2molL−1 KNO3 solution. This method features fast experimentation time, good suitability for field trace mercury analysis and an acceptable electrode lifetime. Analytical performances of the method and the silver interaction were investigated using square wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS).
Experimental
Results and discussion
Conclusion A silver electrode was successfully applied in quantifying mercury in milk matrices using square wave voltammetric procedure. In the present work, the primary goal, on using electrodes, was to verify the possibility of obtaining responses using SWV in the cathodic sweep which are much more convenient since at this level. The novelty of the proposed methodology is rooted in the use of electrodes in breast milk without any pre-treatment or extraction procedure. The reproducibility, sensitivity and accuracy are good, provided the proper instrumental parameters and supporting electrolyte are used. The use of the rotating silver electrode makes the direct analysis of the milk samples possible without any necessity of pre-treatments or chemical preparation stages. The observed recovery percentage values were exceeded 94.0%, which is considered very satisfactory for analytic applications. Adsorption of Hg(II) on the electrodes solid rotating silver (RSE) obeyed to the Langmuir adsorption isotherm. The calculated ΔG°ads value showed that the attack of the RSE in electrolyte (HCl and KNO3) is mainly controlled by a chemisorption process.
Conflict of interest
Acknowledgments The authors wish to express their appreciation to the Hassan 1er University. This study could not have been conducted without their financial supports.
Introduction Being able to rapidly and accurately detect glucose levels in biological environments is of crucial importance to human health, especially in the condition of faah inhibitor [1,2]. In the past several decades, various methods have been developed to measure glucose concentrations, including optical approaches (infrared (IR) spectroscopy, fluorescence spectroscopy, Raman spectroscopy, optical polarization rotation measurement, photo-acoustic probes, and surface plasmon resonance) [3,4], MEMS affinity sensing [5] and electrochemical methods [6,7]. Optical measurement approaches normally require very expensive instruments, significant processing time and highly trained professions; and affinity sensing method can run into nonspecific binding issues. It is the electrochemical glucose sensing that is most studied and demonstrated with high sensitivity, good accuracy, high selectivity, fast response time, low cost and many other outstanding properties [6,8]. Glucose sensing dates back to 1841 when glucose levels were measured through urine, but the correlation between urine and plasma glucose was later found inconsistent [9]. Until now, the monitoring of blood glucose levels has been the only recognized and widely used method for diagnosis and management of diabetes. However, users have to prick their fingers multiple times a day to use these devices, which are a major problem for young children and result in negative consequences for disease management. Finger pricking can also cause transient discomfort, bruise, fainting and blood-borne infection. A noninvasive and simple technique for diagnosis and monitoring of diabetes is thus very desirable. With a direct correlation between blood glucose and salivary glucose, it is possible to simply apply salivary glucose measurements to monitor individual’s health conditions [10,11]. Hence, monitoring of salivary glucose levels can be an alternative prediagnostic method for diabetics and a health indicator for any individuals. The effective immobilization of enzymes onto the electrode surface has been one of the main factors that affect the sensing performance of an enzyme biosensor [12]. LBL assembly technique, among many enzyme immobilization methods, is proven to be a simple and effective method to prepare multilayer films containing the enzymes enabling good uniformity, stability, reproducibility and remarkable sensitivity [13,14].