Applying resonance Rayleigh scattering and spectrofluorimetric techniques for the selective determination of neomycin sulfate using Congo red as a probe: Applications for wastewater analysis.

Two simple, sensitive, and low-cost fluorescence spectroscopy methods for neomycin (NEO) detection were developed. Both methods were based on the interaction between NEO and Congo red (CR) in acidic buffer medium to form an ion-association complex. The quenching effect of the formed ion-association complex on the fluorescence of CR at 421 nm is a basic principle of fluorescence analysis, whilst the resonance Rayleigh scattering (RRS) method was used to enhance the resonance Rayleigh scattering spectrum at 384 nm by adding NEO.

Enhancement of Congo Red-Neomycin Resonance Rayleigh Scattering by Dodecyl Trimethyl Ammonium Bromide and its Application.

A simple, rapid, and convenient method for the determination of neomycin based on the ion association method was proposed. In Britton-Robinson buffer solution, neomycin could react with Congo red to form an ionic association, which in turn reacted with dodecyl trimethyl ammonium bromide to form a ternary ionic association. The three were combined in a 1 : 1 : 1 ratio, which significantly enhanced the resonant Rayleigh scattering intensity at 468 nm.

Hydrolysis of norfloxacin in the hyporheic zone: kinetics and pathways.

Understanding the hydrolysis behavior and pathway of norfloxacin (NOR) in the hyporheic zone (HZ) is important for predicting its environmental persistence. Therefore, the effects of different environmental factors on NOR hydrolysis were investigated, and the hydrolysis pathway of NOR in the HZ was determined by DFT calculations and UPLC/TOF-MS. The hydrolysis process of NOR was consistent with the first-order kinetic.