RESUMO
Two derivatization regents were reacted with bisoprolol (BIS), followed by liquid-chromatography-mass spectrometric analysis. 3-Bromomethyl-propyphenazone (BMP) and dansyl-chloride (Dns-Cl) were reacted via the secondary amino group using a catalyst to accelerate the reaction progress and completeness with minimal reaction byproducts. The sensitivity and the ionization efficiency of both BIS-methyl-propyphenazone (BIS-MP) and BIS-Dns via electrospray ionization were studied. The sensitivity of BIS-MP was superior to BIS-Dns. The derivatization procedure, extraction procedure, and LC-MS method were optimized and validated to achieve the monitoring of BIS in rat serum at a picogram scale. The calibration curve showed a regression coefficient value of 0.999 within a concentration spanning a range of 10-500 pg/mL. The detection limit and quantitation were 4 and 10 pg/mL, respectively. The intraday and inter-day precision values (% relative standard deviation) ranged from 0.53 to 6.91%, whereas the accuracy values (expressed as % error) ranged from -4.20 to -0.77%. The pharmacokinetic parameters were: 15,280 pg/mL for a maximum concentration of BIS (Cmax) at the maximum time (Tmax) of 1 h. BIS's elimination half-life (t1/2) was determined to be 3 h. The value of the area under the concentration-time curve (AUC0 - t) was 34,370 pg/mL h.
RESUMO
A simple extractive spectrofluorimetric strategy for trace determination of mercury(II) ions in water employing procaine hydrochloride (PQ+) as an ion pairing fluorescent tagging reagent has been established. The method was based upon the extraction of PQ+ from aqueous iodide media onto dichloromethane as a ternary complex ion associate [(PQ+)2.(HgI4)2-] at pH 9.0-10.0 with subsequent quenching at λex/em = 268/333 nm. The developed strategy exhibited a linear range 20-140 nM with a lower limit of detection (LOD) 6.1 nM, respectively. Intra and inter-day laboratory accuracy and precision for trace analysis of mercury(II) ions in water were performed. Complexed mercury(II) species in real water samples were evaluated along with chemical speciation and successful comparison with most of the reported methods. The method was validated by standard inductively coupled plasma-optical emission spectrometry (ICP-OES) method in terms of student's t- and F tests at 95% confidence interval. The method offers rapidity, selectivity, cost-effectiveness, robustness, and ruggedness. Graphical Abstract Schematic illustration of the proposed sensing mechanism for mercury(II).
