Fabrication of Chitosan‐Multiwall Carbon Nanotube Nanocomposite Containing Ferri/Ferrocyanide: Application for Simultaneous Detection of D‐Penicillamine and Tryptophan

Abstract

We report a simple and effective strategy for fabrication of the nanocomposite containing chitosan (CS) and multiwall carbon nanotube (MWNT) coated on a glassy carbon electrode (GCE). The characterization of the modified electrode (CS‐MWNT/GC) was carried out using scanning electron microscopy (SEM) and UV–vis absorption spectroscopy. The electrochemical behavior of CS‐MWNT/GC electrode was investigated and compared with the electrochemical behavior of chitosan modified GC (CS/GC), multiwalled carbon nanotube modified GC (MWNT/GC) and unmodified GC using cyclic voltammetry (CV) and electron impedance spectroscopy (EIS). The chitosan films are electrochemically inactive; similar background charging currents are observed at bare GC. The chitosan films are permeable to anionic Fe(CN)63−/4− (FC) redox couple. Electrochemical parameters, including apparent diffusion coefficient for the Fe(CN)63−/4− redox probe at FC/CS‐MWNT/GC electrode is comparable to values reported for cast chitosan films. This modified electrode also showed electrocatalytic effect for the simultaneous determination of D‐penicillamine (D‐PA) and tryptophan (Trp). The detection limit of 0.9 μM and 4.0 μM for D‐PA and Trp, respectively, makes this nanocomposite very suitable for determination of them with good sensitivity.

Magnesium oxide as a heterogeneous catalyst support

“…Typical inorganic precursors, including metal alkoxides and a metal chloride, coincidentally undergo hydrolysis and polycondensation reactions to afford a colloid and gel (Chekin et al 2012d). The basic structure of the solid phase includes from discrete colloidal particles to polymeric networked gel ( Figure 1).…”

“…Then, MgO materials having superb specific surface area have been synthesized by the sol-gel method, combining a hypercritical drying process ( Figure 4) (Chekin et al 2012d). For example, some research interest has progressed on a chemical method of dispersing precipitated Mg(OH) 2 in a polymer matrix (such as PVA, citric acid, glycine, urea, hydrazine, polyethylene glycol, or polyacryslic acid) and managed to obtain nanosized MgO (Minami et al 2012, Sui and Charpentier 2012, Mastuli et al 2014.…”

“…The sol-gel process is one of wet chemistry reactions for the synthesis of metal oxide catalysts through the polymerization of inorganic precursors, including metal alkoxide, metal halide, and colloidal solution (Chekin et al 2012d, Mirzaei and Davoodnia 2012, Tang et al 2012. Typical inorganic precursors, including metal alkoxides and a metal chloride, coincidentally undergo hydrolysis and polycondensation reactions to afford a colloid and gel (Chekin et al 2012d).…”

TiO2 hybrid photocatalytic systems: impact of adsorption and photocatalytic performance

“…These hybrid systems are expected to be industrially effective because nanocarbon material can act as support for tight immobilization by preventing the loss of TiO 2 nanoparticles in a flowing fluid stream (Xu et al 2010, Chekin et al 2012c). Therefore, not only is TiO 2 /nanocarbon hybrid used to remove organic pollutants in aqueous solutions, but it could also remove contaminants from vapors such as NO, CO, and acetyldehyde, decompose biological pollutants, produce hydrogen via photocatalytic splitting of water and photoelectrochemical electrodes (dye-sensitized solar cells), and act as antibiotic catalysts ).…”

Spectrophotometric Determination of Penicillamine in Pharmaceutical Sample using Fe(III)-Tiron System

“…It is of great importance and significance for life science. Up till now, various different methods have already been applied for the determination of penicillamine, such as spectrophotometry [1,2], fluorescence spectrophotometry [3,4], flow injection analysis [5,6], voltammetry [7,8], capillary electrophoresis [9], HPLC method [10], HPLC-UV method [11], LC-UV method [12], chemiluminescence-LC method [13], electrochemical analysis [14], etc. However, most of the methods mentioned above need either complicated and expensive equipment or tedious procedures.…”