A Disposable Carbon Nanotubes‐screen Printed Electrode (CNTs‐SPE) for Determination of the Antifungal Agent Posaconazole in Biological Samples

Abstract

For the first time, the use of carbon nanotubes was exploited for the development of a sensitive electrochemical method for determination of the newly antifungal posaconazole (POS). The electrochemical activity of POS was investigated at the surface of multi‐walled nanotubes (MWNTs) modified electrode. The cyclic voltammograms showed a sharp oxidation peak at potential around 671 mV vs. Ag/AgCl. To reach the assay optimization, factors affecting the method sensitivity have been investigated, such as types of carbon nanotubes and its concentration in the electrode matrix, type of supporting electrolyte, pH, accumulation time and scan rate. A good linear relationship was obtained within the concentration range from 32–1280 ng/ml with the limit of detection and quantification of 11 ng/ml and 33 ng/ml, respectively. The proposed method was successfully applied for the determination of POS in its commercial dosage form, spiked human plasma samples, and dried blood spots. The in vivo results obtained were also used to study the pharmacokinetics of POS in human plasma. The results obtained were validated and found to be in accordance with those obtained by the reference methods.

Electromembrane Extraction of Posaconazole for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometric Detection

“…Compared with previous methods for posaconazole quantification in human plasma or serum samples, the LOD of posaconazole obtained here was lower. In particular, our result was lower than the voltammetric method using a carbon nanotube-screen printed electrode [35] and comparable to those reported using CE coupled to SPE, sample stacking techniques [36,37], and LC coupled to fluorescence detection [38]. Although LC/MS and LC/MS/MS provided relatively low LODs for posaconazole, elaborate sample preparation procedures and sophisticated instrumentation were required [39,40].…”

Microbial Electrochemical Systems: Principles, Construction and Biosensing Applications

“…Electrochemical biosensors are the most common biosensing techniques due to their high specificity and sensitivity, and their ease of use. Also, their use allows the on-line detection of a broad spectrum of analytes in complex matrices (e.g., blood, serum, urine or food) [ 113 , 114 ]. Moreover, the advanced miniaturization of modern microelectronics allows building micro/and nano-electrodes, which are suited for detection of very small volumes of samples (microliters to nano-liters) [ 115 ].…”

New sensing platform of poly(ester-urethane)urea doped with gold nanoparticles for rapid detection of mercury ions in fish tissue

“…In electrochemical systems, studying electron transfer rate at the electrode/solution interface provides information to understand the role of electrode composition(s) in the studied electrochemical process. [46][47][48][49] Here, using cyclic voltammetry, redox reactions of ferricyanide, as a standard redox probe was studied at the modied electrodes with the PUU and PUUnanocomposites (i.e. the PUU doped with each of these nanostructures: (Ag, Au, Pt, Cu, ZnO, CoO 3 , MnO 2 , Al 2 O 3 , and MWCNTs).…”