Sulphamerazine [HRP]

The dehydration reaction of tetraamino porphyrin and 4,4'-biphenyldicarboxaldehyde was performed for the synthesis of a novel covalent organic framework (COF), which was decorated on magnetic Fe3O4 to obtain core-shell structured Fe3O4@COFs nanospheres for the first time, for effective extraction and enrichment of sulfonamides (SAs). The morphology and structure of the synthesized nanospheres were characterized through various methods. The extraction conditions for six SAs including sulfadiazine, sulfamerazine, sulfamethazine, sulfamonomethoxine, sulfamethoxazole, sulfadimethoxine were systematically optimized. Fe3O4@COFs nanospheres were evaluated for magnetic solid-phase extraction. By coupling with high-performance liquid chromatography, a facile and sensitive method was established for the quantitation analysis of six SAs. The method showed good linearity ranging from 1 to 500 ng mL(-1) with R-2 > 0.99, high sensitivity with LODs in the range of 0.2-1 ng mL(-1), and high precision with RSDs <= 6.3%. This method was further applied into determination of SAs in environmental water and food samples, with recoveries in the range of 65.3%-107.3% and RSDs <= 6.7%. These successful applications suggest that the core-shell structured Fe3O4@COFs nanospheres could be used as a potential adsorbent for efficient extraction and analysis of trace SAs. (C) 2019 Elsevier B.V. All rights reserved.

The aim of this work was the development and characterization of a biocompatible microemulsion (ME) containing soybean oil (O), phosphatidylcholine/sodium oleate/Eumulgin (R) HRE40 as the surfactant mixture (S) and water or buffer solution as the aqueous phase (W), for oral delivery of the poorly water-soluble drugs sulfamerazine (SMR) and indomethacin (INM). A wide range of combinations to obtain clear oil-in-water (o/w) ME was observed from pseudo-ternary phase diagrams, which was greater after the incorporation of both drugs, suggesting that they acted as stabilizers. Drug partition studies indicated a lower affinity of the drugs for the oil domain when they were ionized and with increased temperature, explained by the fact that both drugs were introduced inside the oil domain, determined by nuclear magnetic resonance. High concentrations of SMR and INM were able to be incorporated (22.0 and 62.3 mg/mL, respectively). The ME obtained presented an average droplet size of 100 nm and a negative surface charge. A significant increase in the release of SMR was observed with the ME with the highest percentage of O, because of the solubilizing properties of the ME. Also, a small retention effect was observed for INM, which may be explained by the differences in the partitioning properties of the drugs. (c) 2015 Wiley Periodicals, Inc.