l‐Cysteine‐modified silver‐functionalized silica‐based material as an efficient solid‐phase extraction adsorbent for the determination of bisphenol A

Abstract

A new silver-functionalized silica-based material with a core-shell structure based on silver nanoparticle-coated silica spheres was synthesized, and silver nanoparticles were modified using strongly bound l-cysteine. l-Cysteine-silver@silica was characterized by scanning electron microscopy and FTIR spectroscopy. Then, a solid-phase extraction method based on l-cysteine-silver@silica was developed and successfully used for bisphenol A determination prior to HPLC analysis. The results showed that the l-cysteine-silver@silica as an adsorbent exhibited good enrichment capability for bisphenol A, and the maximum adsorption saturation was 20.93 mg/g. Moreover, a short adsorption equilibrium time was obtained due to the presence of silver nanoparticles on the surface of the silica. The extraction efficiencies were then optimized by varying the eluents and pH. Under the optimized conditions, good linearity for bisphenol A was obtained in the range from 0.4 to 4.0 μM (R > 0.99) with a low limit of detection (1.15 ng/mL). The spiked recoveries from tap water and milk samples were satisfactory (85-102%) with relative standard deviations below 5.2% (n = 3), which indicated that the method was suitable for the analysis of bisphenol A in complex samples.

Process Intensification in Gas–Liquid Mass Transfer by Modification of Reactor Design: A Review

“…Balamurugan et al [ 78 ] investigated the effects of operating parameters, such as gas velocity, liquid level in the suction chamber, nozzle diameter, and throat diameter on the mass transfer characteristics of gas–liquid ejectors. In addition, an increase in the nozzle velocity and power input per unit volume (P/V) had shown a positive impact on the mass transfer coefficient and interfacial area.…”

Ion-Trap Mass Spectrometric Analysis of Bisphenol A Interactions With Titanium Dioxide Nanoparticles and Milk Proteins

“…It has been reported that either ethanol solution (75%) or ammonium hydroxide solution (0.5 M) is capable of desorbing BPA off carbon adsorbents [36]. Indeed, the BPA recovery rate increased with increasing solvent polarity, indicating a stronger interaction with BPA when the number of available polar sites in the solvent molecule became greater [39]. At pH ≤ 8, most of the BPA (pK a 9.7) present is neutral, resulting in decreased binding.…”