A novel and sensitive biosensor employing immobilized DNA on a pencil graphite electrode modified with polypyrrole/functionalized multiwalled carbon nanotubes for the determination of 6-mercaptopurine (6-MP) is presented. In the first step, we modified the pencil graphite surface with polypyrrole and functionalized multiwalled carbon nanotubes (MWCNT/ COOH). The developed electrode was characterized by scanning electron microscopy, atomic force microscopy, reflection− absorption infrared spectroscopy, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy. In the other step, we used decreases in the oxidation responses of guanine and adenine as a sign of the interaction of 6-MP with salmon sperm double-stranded DNA using differential pulse voltammetry. The signal of guanine oxidation was linear with respect to the 6-MP concentration in the range of 0.2−100 μmol L −1 with a detection limit of 0.08 μmol L −1 . The modified electrode was utilized for the determination of 6-MP in real samples.

No abstract

No abstract

No abstract

No abstract

The peak potentials recorded were 170, 500 and 830 mV vs. Ag/AgCl/KCl sat for AA, NADH and FA, respectively. The peak currents were linearly dependent on AA, NADH and FA concentrations using square wave voltammetry (SWV) method at the ranges of 0.008-251, 1.0-650, and 3.0-700 mmol L À1 , with detection limits of 0.005, 0.5, and 1.0 mmol L À1 , respectively.

In this research, we report the preparation of a high sensitive voltammetric sensor for electrocatalytic determination of hydroxylamine (HX) in the presence of thiosulfate (TS). We describe the synthesis and characterization of CdO nanoparticles (CdO/NPs) with transmission electron microscopy (TEM) and X‐ray diffraction (XRD) methods. At an optimum condition, the two peaks are separated ca. 0.58 and 0.92 V for HX and TS at the surface of the proposed sensor. Square wave voltammetry (SWV) of HX exhibited two linear dynamic ranges with a detection limit (3σ) of 0.06 µmol L−1. The propose sensor was used for determination of HX in water samples.

Dasatinib or sprycel is an anticancer drug for treatment of chronic myelogenous leukemia, prostate cancer, and some of the other cancers with several adverse effects.