On the basis of previously established mechanism of cefetamet (CEF) reduction, two methods were suggested for CEF determination-differential pulse polarographic and differential pulse adsorptive stripping voltammetric method. Two pH values were chosen, 2.0 and 8.4, where the electrochemical process was defined as one four-electron and two two-electron processes, respectively. The methods were performed in Britton-Robinson (BR) buffer and the corresponding calibration graphs were constructed and statistical parameters were evaluated. Applying the AdSV method at pH 2.0 linearity was achieved from 2 x 10(-8) to 2 x 10(-7) M with limit detection and limit determination of 4 x 10(-9) and 1.4 x 10(-8) M, respectively. At pH 8.4, the linearity was obtained between 6 x 10(-8) and 6 x 10(-7) M, with limit detection and limit determination of 1.5 x 10(-8) and 5 x 10(-8) M, respectively. Since the AdSV method enabled lower concentrations of CEF to be determined, this method was tested for CEF determination in spiked urine samples, and DPP method was used as a comparative one.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/s0731-7085(03)00197-3 | DOI Listing |
Adv Mater
January 2025
Department of Chemistry, University College London, London, WC1E 7JE, UK.
Long-standing challenges including notorious side reactions at the Zn anode, low Zn anode utilization, and rapid cathode degradation at low current densities hinder the advancement of aqueous zinc-ion batteries (AZIBs). Inspired by the critical role of capping agents in nanomaterials synthesis and bulk crystal growth, a series of capping agents are employed to demonstrate their applicability in AZIBs. Here, it is shown that the preferential adsorption of capping agents on different Zn crystal planes, coordination between capping agents and Zn ions, and interactions with metal oxide cathodes enable preferred Zn (002) deposition, water-deficient Zn ion solvation structure, and a dynamic cathode-electrolyte interface.
View Article and Find Full Text PDFSmall Methods
January 2025
Hunan Provincial Key Laboratory of Chemical Power Sources, College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, P. R. China.
Anode-less sodium metal batteries (SMBs) suffer from the formation of Na dendrites and inactive Na on an anode substrate though showing advantages of high energy densities and low costs. Herein, N,O co-doped carbon spheres (NOCS), which are synthesized via a scalable polymerization and pyrolysis method, are employed as a thin and stable sodiophillic nucleation layer on the Cu foil. Combined with electrochemical measurements, Na deposition morphology observations and density functional theory calculations, it is revealed that the introduced N and O heteroatoms can greatly enhance the adsorption of Na on the carbon substrate and reduce the nucleation overpotential, thus forming sufficient seeding sites and guiding homogeneous Na deposition.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Huazhong University of Science and Technology, School of Chemistry and Chemical Engineering, CHINA.
Porous organic polymers have shown great potential in photocatalytic CO2 reduction due to their unique tunable structure favoring gas adsorption and metal sites integration. However, efficient photocatalysis in porous polymers is greatly limited by the low surface reactivity and electron mobility of bulk structure. Herein, we incorporate TiO2 nanoparticles and Ni(II) sites into a layered cationic imidazolium polymer (IP), in which the imidazolium moieties and free anions can stabilize the key intermediates and enhance the reaction kinetics of CO2 reduction.
View Article and Find Full Text PDFMikrochim Acta
December 2024
Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt.
The detection of 4-chloro-2-methylphenoxyacetic acid (CMPA) herbicide is crucial due to the potential health risks linked to exposure through drinking water, air, and food, which may adversely affect liver and kidney functions. To address this environmental concern and promote sustainable agriculture, a sensitive carbon paste sensor incorporating a composite material was developed. The composite sensor is based on porous cobalt-1,4-benzenedicarboxylate metal-organic framework and exfoliated montmorillonite nanolayers (Co-OF/MMt).
View Article and Find Full Text PDFTalanta
December 2024
São Carlos Institute of Chemistry, University of São Paulo, Av. João Dagnone, 1100, 13566-590, São Carlos, SP, Brazil. Electronic address:
This study reports the development and implementation of a straightforward, rapid, and cost-effective voltammetric technique for piroxicam (PIR) detection at nanomolar concentrations in biological and environmental samples. The method involved the use of a screen-printed electrode (SPE) enhanced with a combination of Printex L6 carbon (PL6C) and polyaniline-based activated carbon (PAC) on a chitosan film crosslinked with epichlorohydrin (CTS:EPH). The detection was carried out using square-wave adsorptive anodic stripping voltammetry (SWAdASV) in a 0.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!