Different artificial sweeteners were studied in blood medium as electrolyte by cyclic voltammetric technique using modified glassy carbon electrode with carbon nanotubes to determine the diffusion coefficient for the redox current peaks of artificial sweetener by Randles-Sevcik equation. It was determined the viscosity of the blood medium after the addition of the artificial sweetener to find the relationship between the viscosity and the diffusion of sweetener ions in blood medium and reach to the electrode. The high viscosity of blood and addition of the sweetener compound which causes impedes of diffusion the ions for redox current of the reaction on the surface of the sensor. So, the results of diffusion coefficient values depended on the viscosity of blood medium. Sorbitol compound has a higher viscosity in blood medium with lower diffusion coefficient values of redox current peaks and mannitol has lower viscosity in the series of the sweetener compounds in blood medium with high values of diffusion coefficient for the redox current peaks.

Gold coated mesoporous silica magnetic nanocomposite (mSiO2@Fe3O4 @Au) was synthesized using ethylene glycol (EG) as template at two different ratios of EG: TEOS of 0.1 and 0.6. The chemistry, morphology, optical and magnetic properties of the obtained nanocomposites were characterized by Fourier Transform (FTIR), Scanning Electron Microscopy (SEM), Transverse Electron Microscopy (TEM), Atomic Force Microscopy (AFM), X-ray Diffractometry (XRD), Vibrating Sample Magnetometry (VSM) and UV-Vis absorption spectroscopy. The mean diameter of amino-functionalized SiO2 NPs was measured 70 nm. The range of porosity ranged from 10 to 100 nm, with larger distribution of pore size of less than 20 nm. The average radius of pores on SiO2 NPs calculated by BJH method is approximately 15.5 nm. Magnetic nanoparticles (MNPs) with the average diameter of 34 nm were synthesized and then coated by AuNPs with an average size of 25 nm synthesized via a two-step process of dative and reduction method. The average size distribution of mSiO2@Fe3O4@Au nanocomposite was measured about 157 nm. The nanocomposite exhibited a significant red-shift in surface plasmon resonance wavelength (?SPR ˜ 800 nm), which coincides with NIR biomedical applications.