No abstract

Synthesis of zirconium oxide (zirconia) (ZrO2) nanoparticles (ZNPs) through gel combustion technique as well as their structural and morphological characterization using XRD, SEM and TEM forms the central theme of this work. Along with structural and morphological characterization, an electrochemical detection of Serotonin (5-HT) is described using ZNPs Modified Carbon Paste Electrode (ZMCPE). The XRD results confirms that particles are well crystallized in tetragonal phase with average particle size of 35 nm. From SEM it can be observed that, the materials formed is porous in nature and the particles are seems to be uniform in size. HRTEM reveals that, the particles size in the order of 30–40 nm and the crystallinity was supported by SAED pattern of the ZNPs and these results are in close agreement with the results obtained through XRD. The Electrochemical detection of Serotonin (5-HT) was performed through cyclic voltammetric and differential pulse voltammetric method at different circumstances like concentration of the analyte, applied potentials and pH of the medium. The DPV experiments shows that ZMCPE displays high sensitivity for the quantification of serotonin (5-HT) in the range 10–50 μM and the limit of detection is 0.585 μM. The ZMCPE gives good reproducibility, high catalytic activity and sensitivity for the electrochemical quantification of Serotonin.

In this investigation, SnO2 nanoparticles are prepared through environmental benign method using Nelumbo nucifera (lotus leaf) leaves extract as a reducing agent without any other reagents. The phase formation and the morphology of the as-synthesized SnO2 nanoparticles are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The nanoparticle size is obtained using selected area diffraction patterns of transmission electron microscope (TEM). The synthesized material modified glassy carbon electrode (GCE) is used for electrochemical detection of the dopamine (DA). In cyclic voltammetry (CV), the modified GCE shows effective electrochemical sensing performance than the bare GCE electrode. The limit of detection (LOD) and limit of quantification (LOQ) of DA were calculated by differential pulse voltammetry (DPV). Aforementioned material has high sensitivity and selectivity towards DA oxidation through electrochemical sensing.

Cerium doped zirconia (ZrO2) nanoparticles are used in the electrochemical investigation of one of the important neurotransmitter Dopamine. Cerium doped ZrO2 nanoparticles finds an interesting application for the electrochemical detection of Dopamine. These cerium doped zirconia nanoparticles were synthesized by environmental benign co‐precipitation method. The phase formation and the crystallinity of the synthesized nanoparticles were characterized by X‐ray diffraction and it was in cubic phase. The morphology of the nanoparticles was characterized by field‐emission scanning electron microscopy and the particle size was measured by using high resolution transmission microscopy. The average particle size was measured to be 18 nm. Additionally, the effectiveness of cerium doped zirconia nanoparticles modified carbon paste electrode (Ce‐ZrO2/MCPE) was evaluated by using cyclic voltammetric technique, to assess the application as electrochemical sensor for Dopamine. Differential pulse voltammetry method is used for the detection of Dopamine, the limit of detection was found to be 3.6 μmol L−1 based on (S/N=3). This shows high stability and low detection level at modified electrode. In addition, modified electrodes are also been used the detection of Dopamine in real time sample analyses with satisfactory results.