ABSTRACT
A gas chromatographic (GC) procedure has been developed for the determination of fluorouracil (5-FU) after pre-column derivatization with hexafluoroacetylacetone. GC separation was from column DB-1 (30 m × 0.32 mm id) and the determination was by flame-ionization detection. The derivatization conditions were optimized at pH 4, heating at 90°C for 40 min and extraction of the derivative was in chloroform. Using the conditions nucleobases cytosine, uracil, thymine, adenine and guanine separated completely from fluorouracil. The linear calibration range and LOD for 5-fluorouracil were 0.5-40.0 and 0.2 µg/mL, respectively. The derivatization, elution and separation were repeatable in terms of retention time and peak height/peak area (n = 5) and relative standard deviations (RSD) were within 3.5%. The method was applied for the analysis of serum spiked with 5-FU with recovery of 95.5-97.5% with RSD 1.5-3.1%.
Subject(s)
Fluorouracil , Calibration , Chromatography, Gas/methods , Flame Ionization , Indicators and ReagentsABSTRACT
In present study, we proposed the application of a deep eutectic solvent (DES) made up of choline chloride (ChCl) and oxalic acid (Ox) for the dissolution of different edible mushroom samples for the determination of selenium (Se) and arsenic (As) ions. Therefore, an innovative, green, novel, and inexpensive method based on ChCl-Ox as the DES was developed for the determination of Se and As ions in mushroom species by graphite furnace-atomic absorption spectrometry. The important analytical parameters were also optimized. The LODs for Se and As ions were found to be 0.32 and 0.50 µg/L, respectively. The LOQs for Se and As ions were found to be 1.06 and 1.65 µg/L, respectively. The RSD was observed to be less than 5% for both analyte ions. The accuracy of the developed method was confirmed by analyzing mushroom powder Certified Reference Material CS-M-3 (Boletus edulis). The developed technique was effectively useful for the determination of Se and As ions in different species of mushroom samples from Turkey.
Subject(s)
Arsenic/analysis , Chemical Fractionation/methods , Selenium/analysis , Solvents/chemistry , Agaricales/chemistry , Choline/chemistry , Food Analysis/methods , Green Chemistry Technology/methods , Ionic Liquids/chemistry , Limit of Detection , Oxalic Acid/chemistry , Spectrophotometry, Atomic/methodsABSTRACT
A simple, fast, green, sensitive and selective ultrasonic assisted deep eutectic solvent liquid-phase microextraction technique was used for preconcentration and extraction of cadmium (Cd) in water and food samples by electrothermal atomic absorption spectrometry (ETAAS). In this technique, a synthesized reagent (Z)-N-(3,5-diphenyl-1H-pyrrol-2-yl)-3,5-diphenyl-2H-pyrrol-2-imine (Azo) was used as a complexing agent for Cd. The main factors effecting the pre-concentration and extraction of Cd such as effect of pH, type and composition of deep eutectic solvent (DES), volume of DES, volume of complexing agent, volume of tetrahydrofuran (THF) and ultrasonication time have been examined in detail. At optimum conditions the value of pH and molar ratio of DES were found to be 6.0 and 1:4 (ChCl:Ph), respectively. The detection limit (LOD), limit of quantification (LOQ), relative standard deviation (RSD) and preconcentration factor (PF) were observed as 0.023â¯ngâ¯L-1, 0.161â¯ngâ¯L-1, 3.1% and 100, correspondingly. Validation of the developed technique was observed by extraction of Cd in certified reference materials (CRMs) and observed results were successfully compared with certified values. The developed procedure was practiced to various food, beverage and water samples.
Subject(s)
Cadmium/analysis , Cadmium/isolation & purification , Food Analysis/methods , Liquid Phase Microextraction/methods , Spectrophotometry, Atomic , Ultrasonic Waves , Water/chemistry , Cadmium/chemistry , Food Contamination/analysis , Hydrogen-Ion Concentration , Limit of Detection , Solvents/chemistryABSTRACT
An improved GC method in terms of sensitivity and decrease in the analysis time has been developed for the analysis of eight guanidino compounds: guanidine (G), methylguanidine (MG), creatinine (CTN), guanidinoacetic acid (GAA), guanidinobutyric acid (GBA), guanidinopropionic acid (GPA), argenine (Arg), and guanidinosuccinic acid (GSA), using isovaleroylacetone (IVA) and ethyl chloroformate (ECF) as derivatizing reagents. The separation was obtained from column HP-5 (30 m × 0.32 mm i.d.) with film thickness of 0.25 µm within 11 min. The linear calibrations were obtained with 0.5 to 50 µg/mL with coefficient of determination (R(2)) within 0.9969 - 0.9998. Limits of detections (LODs) were within 5 - 140 ng/mL. The derivatization, separation and determination was repeatable (n = 6) with relative standard deviation (RSD) within 1.2 - 3.1%. The guanidino compounds were determined in deproteinized serum of healthy volunteers and uremic patients within below LOD to 8.8 µg/mL and below LOD to 43.99 µg/mL with RSD within 1.4 - 3.6%. The recovery of guanidino compounds calculated by standard addition from serum was within 96.1 - 98.9%, with RSD 1.4 - 3.6%.
Subject(s)
Arginine/analysis , Butyric Acid/analysis , Chromatography, Gas/methods , Creatinine/analysis , Guanidine/analysis , Uremia/blood , Acetone/chemistry , Boric Acids/chemistry , Butyrates/analysis , Calibration , Formic Acid Esters/chemistry , Glycine/analogs & derivatives , Glycine/analysis , Guanidines/analysis , Healthy Volunteers , Humans , Hydrogen-Ion Concentration , Ketones/chemistry , Limit of Detection , Methylguanidine/analysis , Propionates/analysis , Reference Values , Reproducibility of Results , Succinates/analysisABSTRACT
A sensitive and simple spectrofluorimetric method has been developed for the analysis of famotidine, from pharmaceutical preparations and biological fluids after derivatization with benzoin. The reaction was carried out in alkaline medium with measurement of fluorescence intensity at 446 nm with excitation wavelength at 286 nm. Linear calibration was obtained with 0.5-15 µg/ml with coefficient of determination (r(2)) 0.997. The factors affecting the fluorescence intensity were optimized. The pharmaceutical additives and amino acid did not interfere in the determination. The mean percentage recovery (n=4) calculated by standard addition from pharmaceutical preparation was 94.8-98.2% with relative standard deviation (RSD) 1.56-3.34% and recovery from deproteinized spiked serum and urine of healthy volunteers was 98.6-98.9% and 98.0-98.4% with RSD 0.34-0.84% and 0.29-0.87% respectively.