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1.
A rapid and sensitive ultra-performance liquid chromatography–tandem mass spectrometry method with electrospray ionization (UPLC–ESI–MS/MS) for analysis of B-group vitamins in honey has been presented. Aim of this study is the characterization of different types of Turkish honeys according to B-group vitamins. Vitamins were determined in 17 different types of Turkish honey samples by UPLC–ESI–MS/MS. Heather honey samples were distinguished among the studied honeys with the richest vitamin content with 286.10?mg/kg, and it is followed by sunflower honey and thyme honey with the total vitamin contents of 206.01 and 163.27?mg/kg, respectively. The presence of vitamin B 1 (thiamine), vitamin B 2 (riboflavin), vitamin B 3 (nicotinamide, B 3N and nicotinic acid, B 3H), vitamin B 6 (pyridoxine), and vitamin B 9 (folic acid) was detected in all the honey samples analyzed. Moreover, vitamin B 5 (pantothenic acid) was observed in most of them. Vitamin B 12 (cyanocobalamin) and vitamin B 7 (biotine) were not detected in the studied honey samples. Turkish honey samples showed efficacious vitamin content for the consumers. 相似文献
2.
A rapid method was developed to determine both types of vitamins in Rhodiola imbricata root for the accurate quantification of free vitamin forms. Rapid resolution liquid chromatography/tandem mass spectrometry (RRLC–MS/MS) with electrospray ionization (ESI) source operating in multiple reactions monitoring (MRM) mode was optimized for the sequential analysis of nine water-soluble vitamins (B 1, B 2, two B 3 vitamins, B 5, B 6, B 7, B 9, and B 12) and six fat-soluble vitamins (A, E, D 2, D 3, K 1, and K 2). Both types of vitamins were separated by ion-suppression reversed-phase liquid chromatography with gradient elution within 30 min and detected in positive ion mode. Deviations in the intra- and inter-day precision were always below 0.6% and 0.3% for recoveries and retention time. Intra- and inter-day relative standard deviation (RSD) values of retention time for water- and fat-soluble vitamin were ranged between 0.02–0.20% and 0.01–0.15%, respectively. The mean recoveries were ranged between 88.95 and 107.07%. Sensitivity and specificity of this method allowed the limits of detection (LOD) and limits of quantitation (LOQ) of the analytes at ppb levels. The linear range was achieved for fat- and water-soluble vitamins at 100–1000 ppb and 10–100 ppb. Vitamin B-complex and vitamin E were detected as the principle vitamins in the root of this adaptogen which would be of great interest to develop novel foods from the Indian trans-Himalaya. 相似文献
3.
In this paper, the chromatographic behavior of some water-soluble vitamins was studied on a new p- tert-butyl-calix[8]arene-bonded silica gel stationary phase (CABS, 5 μm particle size, the bonded amount 0.071 mmol g −1) by using vitamin standards as probes for HPLC. The comparative study of the separation of these compounds was done by using CABS and ODS as stationary phases under the same chromatographic conditions. The better separation of six vitamins including: B 1, B 2, B 6, B 12, C, and nicotinic acid (B 5), on CABS can be achieved by using isocratic mode with methanol-phosphate buffer (25:75, (v/v)) as mobile phase within 20 min. The results show that the calix[8]arene-bonded phase exhibits high selectivity for water-soluble vitamins. We found that the elution order of B 2 (12.08 min) and B 12 (16.42 min) on CABS was very different from that of B 12 (7.76 min) and B 2 (18.47 min) on ODS, which indicate that different retention mechanisms exist in the chromatographic processes of the two stationary phases. According to the chromatographic data, it can be concluded that various chromatographic retention mechanisms are responsible for the separation of above compounds on CABS, such as hydrophobic interaction, hydrogen bonding interaction, and π-π interaction. The new packing has two advantages over ODS. On one hand, the polar and ionized analytes, such as C and B 5, exhibited stronger affinities to CABS because of hydrogen bonding interaction. On the other hand, the retention of B 2 and B 12 became shorter on CABS with weaker hydrophobicity in comparison with ODS. The new material exhibits the promising application in the separation of water-soluble vitamins. 相似文献
4.
A sensitive and selective liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the determination of several water-soluble vitamins, namely vitamins B 1, B 2, B 6 (pyridoxine, pyridoxal, and pyridoxamine), and PP (nicotinamide and nicotinic acid), pantothenic acid, and folic acid was developed and validated. The analytes were characterized by means of their electrospray (ESI) and atmospheric pressure chemical ionization (APCI) mass spectra. In general, the positive ion spectra were 100- to 1000-fold more intense than the corresponding negative ion ones. Chromatography of water-soluble vitamins was obtained by using a reversed-phase C16 Amide (15 cm, 5 μm) column and a mobile phase made of ammonium formate buffer (20 mM, pH 3.75)/methanol under gradient elution conditions. Linearity of the MS response was observed over three to four orders for both ESI and APCI, and limits of detection were in the low μg/l range for both the ionization techniques. In particular, the sensitivity of ESI was about two- to five-fold higher for all vitamins except PP vitamers, for which APCI produced a better response. Precision calculated at two concentration levels (0.05 and 1.0 mg/l) was within 0.2-7.4% for all intra- and inter-day determinations and for all analytes. The LC-ESI-MS/MS method was applied to the quantitative analysis of the natural content of vitamins in typical Italian pasta samples, as well as in fortified pasta samples produced for the US market. 相似文献
5.
A novel, simple, and effective ion‐pair cloud‐point extraction coupled with a gradient high‐performance liquid chromatography method was developed for determination of thiamine (vitamin B 1), niacinamide (vitamin B 3), pyridoxine (vitamin B 6), and riboflavin (vitamin B 2) in plasma and urine samples. The extraction and separation of vitamins were achieved based on an ion‐pair formation approach between these ionizable analytes and 1‐heptanesulfonic acid sodium salt as an ion‐pairing agent. Influential variables on the ion‐pair cloud‐point extraction efficiency, such as the ion‐pairing agent concentration, ionic strength, pH, volume of Triton X‐100, extraction temperature, and incubation time have been fully evaluated and optimized. Water‐soluble vitamins were successfully extracted by 1‐heptanesulfonic acid sodium salt (0.2% w/v) as ion‐pairing agent with Triton X‐100 (4% w/v) as surfactant phase at 50°C for 10 min. The calibration curves showed good linearity (r 2 > 0.9916) and precision in the concentration ranges of 1‐50 μg/mL for thiamine and niacinamide, 5–100 μg/mL for pyridoxine, and 0.5–20 μg/mL for riboflavin. The recoveries were in the range of 78.0–88.0% with relative standard deviations ranging from 6.2 to 8.2%. 相似文献
6.
Seven water-soluble vitamins: thiamine hydrochloride (B 1), riboflavin hydrochloride (B 2), pyridoxine hydrochloride (B 6), calcium pantotenate (B 5), ascorbic acid (C), folic acid (B 9), and biotin (H, B 7) were separated using the micellar electrokinetic chromatographic (MEKC) method in a single run with the electrolyte solution consisting of 100 mM H 3BO 3, 5 mM Na 2B 4O 7, and 30 mM sodium dodecylsulphate (SDS). The separation was achieved within 8 min. and the detection was performed at 200 nm. The calibration graphs plotted with six concentrations of each vitamin were linear with the determination coefficient r > 0.999. The method was applied for quantification of vitamins B 1, B 2, B 5, B 6, B 9, C, and H in novel feed for laboratory animals. The sample preparation involved solid-phase extraction of the vitamins, used prior to the MEKC analysis. The attained precision level was good with the recoveries between 98.4% and 105.6%. The simplicity of the procedure should make it highly useful for feed quality control in husbandry and the animal feed industry. 相似文献
7.
Titrations of commercial diaminobutane (DAB) and polyamidoamine (PAMAM) dendrimers by vitamins C (ascorbic acid, AA), B 3 (nicotinic acid), and B 6 (pyridoxine) were monitored by 1H NMR spectroscopy using the chemical shifts of both dendrimer and vitamin protons and analyzed by comparison with the titration of propylamine. Quaternarizations of the terminal primary amino groups and intradendritic tertiary amino groups, which are nearly quantitative with vitamin C, were characterized by more or less sharp variations (Δ δ) of the 1H chemical shift ( δ) at the equivalence points. The peripheral primary amino groups of the DAB dendrimers were quaternarized first, but not selectively, whereas a sharp chemical‐shift variation was recorded for the inner methylene protons near the tertiary amines, thereby indicating encapsulation, when all the dendritic amines were quaternarized. With DAB‐G5‐64‐NH 2, some excess acid is required to protonate the inner amino groups, presumably because of basicity decrease due to excess charge repulsion. On the other hand, this selectivity was not observed with PAMAM dendrimers. The special case of the titration of the dendrimers by vitamin B 6 indicates only dominant supramolecular hydrogen‐bonding interactions and no quaternarization, with core amino groups being privileged, which indicates the strong tendency to encapsulate vitamins. With vitamin B 3, a carboxylic acid, titration of DAB‐G3‐16‐NH 2 shows that only six peripheral amino groups are protonated on average, even with excess vitamin B 3, because protonation is all the more difficult due to increased charge repulsion, as positive charges accumulate around the dendrimer. Inner amino groups interact with this vitamin, however, thus indicating encapsulation presumably with supramolecular hydrogen bonding without much charge transfer. 相似文献
8.
In the paper, a new kind of vitamin B 12 (acquo-cobalamine) chemically modified electrode was fabricated and applied in capillary zone electrophoresis coupled with amperometric detection (CZE-AD) for simultaneous determination of six antioxidants in fruits and vegetables. The catalytic electrochemical properties of the chemically modified electrode could obviously enhance oxidation peak heights responses by about five times to glutathione, ascorbic acid, vanillic acid, chlorogenic acid, salicylic acid, and caffeic acid compared with common carbon disk electrode. Furthermore, the effects of working electrode potential, pH and concentration of running buffer, separation voltage and injection time on CZE-AD were investigated. Under the optimum conditions, the six analytes could be completely separated and detected in a borate-phosphate buffer (pH 8.4) within 15 min. Their linear ranges were from 2.5 × 10 −7 to 1.0 × 10 −4 mol L −1 and the detection limits were as low as 10 −8 mol L −1 magnitude ( S/ N = 3). The proposed method has been successfully employed to monitor the six analytes in practical samples with recoveries in the range 96.0-106.0% and RSDs less than 5.0%. Above results demonstrate that capillary zone electrophoresis coupled with electrochemical detection using vitamin B 12 modified electrode as detector is of convenient preparation, high sensitivity, good repeatability, and could be used in the rapid determination of practical samples. 相似文献
9.
In this work, a simple and rapid analytical procedure was applied for simultaneous determination of folic acid (vitamin B 0), thiamin (vitamin B 1), riboflavin (vitamin B 2) and pyridoxal (vitamin B 6) based on the absorbance data in the pH range 2.0‐12.0 at 25 °C using parallel factor analysis (PARAFAC). The effect of the pH as the most important factor on the sensitivity of the determination was studied. The spectral data were recorded in 400‐650 nm intervals and a 2‐12 pH range for all four vitamins. The calibration set was constructed in the concentration ranges of 4‐22, 1‐20, 6‐26, and 4‐20 μg mL ?;1 for B 6,B 2,B 1 and B 0, respectively. The root mean squares errors of prediction for the prediction set, (RMSEP), are 0.65, 0.63, 1.13 and 0.34 for B 0,B 1,B 2 and B 6, respectively. The recovery percent for the validation set are in the range of 90.6 to 107.0%. The effect of the experimental conditions and diverse species were discussed. The optimum values of these factors were searched according to the relative standard deviation of the prediction set of mixtures solutions. 相似文献
10.
Hydrophilic interaction liquid‐chromatography (HILIC) in conjunction with diode array detection has been applied for the separation of selected‐water‐soluble vitamins using an end‐capped HILIC‐diol column. Vitamins with significant biological importance, such as thiamine (B 1), riboflavin (B 2), nicotinic acid (B 3), nicotinamide (B 3), pyridoxine (B 6), folic acid (B 9), cyanocobalamin (B 12) and ascorbic acid (vitamin C) were simultaneously separated. Chromatographic conditions including type and percentage of organic modifier in the mobile phase, pH, type and concentration of buffer salt and flow rate were investigated. ACN was shown to offer superior separation for the compounds tested as compared to methanol, isopropanol and THF. Isocratic separation and analysis were achieved for six vitamins (B 1, B 2, nicotinic acid/nicotinamide, B 6 and C) at ACN–H 2O 90:10, containing ammonium acetate 10 mM, triethylamine 20 mM, pH 5.0, using a flow rate of 0.8 mL/min, while a gradient was necessary to resolve a mixture of all eight water‐soluble vitamins. The HILIC method was validated and successfully applied to the analysis of a pharmaceutical formulation and an energy drink negating the need for time consuming clean‐up steps. 相似文献
11.
An improved and simplified analytical method which offers rapid, accurate determination and identification of phenolic compounds in honey samples is reported. The honey samples were diluted by acidified water (pH 2), and analyzed by HPLC–ESI-MS/MS. Simultaneously determination of phenolic acids and flavonoids was carried out by a liquid chromatography–mass spectrometry. Comparison between atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) was performed by analysis of standards. Fragmentation of analytes for subsequent selective Multiple Reaction Monitoring (MRM) analysis was investigated in negative mode. Sample preparation without separation of sugars and clean-up procedure, followed by fast chromatographic separation using a narrow-bore column C18 (50 mm × 2.1 mm, 3 μm) allowed the analysis to be completed in a short run time. LODs were ranged between 1 and 15 ng L −1 for p-coumaric acid and naringenin, respectively. The method was applied for determination of phenolic acids and flavonoids in honey samples from different botanical origin. 相似文献
12.
Due to the importance of B 1 and B 6 vitamins for human health it is useful to develop new cheap and rapid methods for their determination. Voltammetric behavior of these vitamins on a pencil graphite electrode was investigated using cyclic voltammetry in different media. Direct quantitative determination of the two vitamins, one in the presence of the other, was done by differential pulse voltammetry. Vitamin B 1 was electroactive only in a NaOH solution generating two irreversible oxidation peaks; the first peak obtained at 250 mV is well-defined and was used in quantitative determinations. In case of vitamin B 6, a well-defined oxidation peak was observed in all investigated supporting electrolytes except for HCl. The linear concentration ranges were 10 ?5–10 ?3 M for vitamin B 1 in a NaOH solution and 5 × 10 ?6–10 ?3 M for vitamin B 6 in an acetate buffer solution. The obtained detection limits were 5.34 × 10 ?6 M and 2.81 × 10 ?6 M for vitamin B 1 and vitamin B 6, respectively. The developed method is simple and rapid and it was successfully applied in the determination of the two vitamins in pharmaceuticals. 相似文献
13.
The use of the RP-HPLC official method of the International Honey Commission (IHC) for the determination of 5-hydroxymethylfurfural (HMF) in strawberry tree honey ( Arbutus unedo, a typical Sardinian honey) has brought to light a specific and heavy chromatographic interference that prevents accurate quantification. The interference has been identified as homogentisic acid (HA), i.e. the marker of the botanical origin of the honey. For this reason, an alternative RP-HPLC method is proposed. The bias-free method allows a complete separation of HMF from HA to the baseline level and is faster and more precise than the RP-HPLC official method: the detection and quantification limits are 1.9 and 4.0 mg kg −1, respectively, whereas the repeatability is ca. 2% in the HMF concentration range of 5-140 mg kg −1. 相似文献
14.
Simultaneous determination of the fat-soluble vitamins A and E and the water-soluble vitamins B 1, B 2 and B 6 has been carried using a screening method from fluorescence contour graphs. These graphs show different colour zones in relation to the fluorescence intensity measured for the pair of excitation/emission wavelengths. The identification of the corresponding excitation/emission wavelength zones allows the detection of different vitamins in an aqueous medium regardless of the fat or water solubility of each vitamin, owing to the presence of a surfactant which forms micelles in water at the used concentration (over the critical micelle concentration). The micelles dissolve very water insoluble compounds, such as fat-soluble vitamins, inside the aggregates. This approach avoids the use of organic solvents in determining these vitamins and offers the possibility of analysing fat- and water-soluble vitamins simultaneously. The method has been validated in terms of detection limit, cut-off limit, sensitivity, number of false positives, number of false negatives and uncertainty range. The detection limit is about g L –1. The screening method was applied to different samples such as pharmaceuticals, juices and isotonic drinks. 相似文献
15.
A method to covalently attach combinations of six different B vitamins provided an avenue to new functional thermosets without multi‐step coupling reactions. The melt polymerization strategy required no organic solvent and facilitated covalent attachment of OH (B 1, B 2, B 5, B 6) or COOH (B 7, B 9) groups on B vitamins via Fischer esterification. Characterization of model reactions with LC/MS, FTIR, and GPC confirmed covalent attachment. Based on control experiments, B vitamins demonstrated unexpected thermal stability and appreciable solubility in the melt polymerization. This approach was demonstrated with citric acid and diglycerol, but has wide‐ranging potential for other polar monomers with negative octanol–water partition coefficients (LogP). © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3308–3316 相似文献
16.
The purpose of this study was to optimize chromatographic and detection conditions for the simultaneous determination of water-soluble
vitamins in multi-vitamin dietary supplements using a single chromatographic run. An approach using liquid chromatography
with diode array and/or mass spectrometry for quantitation of seven B-complex vitamins [thiamine (B 1), riboflavin (B 2), nicotinamide (B 3), pyridoxine (B 6) pyridoxine, biotin, pantothenic acid, and folic acid] in multi-vitamin/multi-mineral daily supplements is described. This
approach utilizes a reversed phase C18 column (4 μm; i.d.: 250×2.0 mm) with a gradient mobile elution profile, performed at
a flow rate of 0.25 ml/min. After a 5-min isocratic elution at 100% A (0.1% formic acid in water), a linear gradient to 50%
A and 50% B (0.1% formic acid in acetonitrile) at 15 min and then to 5% A and 95% B at 17 min was employed. Detection was
performed with a photodiode array detector (DAD) in sequence with a triple-quad mass spectrometer in the multiple reaction
mode (MS-MRM). Although good chromatographic separation of ascorbic acid was also obtained in extracts from multi-vitamin/multi-mineral
supplements, the ascorbic acid could not be quantified properly due to rapid oxidation catalyzed by the minerals. This method
was initially applied to determine water-soluble vitamins in representative multi-vitamin/multi-mineral tablets following
the extraction of ground samples with a phosphate buffer (10 m M, pH 2.5). For multi-vitamin supplement tablets, this approach does not require any sample clean-up/pre-concentration steps
except for centrifugation and filtration of the extract.
相似文献
17.
In this article, we describe a dipstick based immunochemiluminescence (immuno-CL) biosensor for the detection of vitamin B 12 in energy drinks. The method is a direct competitive type format involving the immobilization of vitamin B 12 antibody on nitrocellulose membrane (NC) followed by treatment with vitamin B 12 and vitamin B 12–alkaline phosphatase conjugate to facilitate the competitive binding. The dipstick was further treated with substrate disodium 2-chloro-5-(4-methoxyspiro {1,2-dioxetane-3,2¢-(5¢-chloro)tricyclo[3.3.1.13,7]decan}-4-yl)-1-phenyl phosphate (CDP-Star) to generate chemiluminescence (CL). The number of photons generated was inversely proportional to the vitamin B 12 concentration. After systematic optimization, the limit of detection was 1 ng mL −1. The coefficient of variation was below 0.2% for both intra- and inter-assay precision. Vitamin B 12 was extracted from energy drinks with recovery ranged from 90 to 99.4%. Two different energy drinks samples were analyzed, and a good correlation was observed when the data were compared with a reference enzyme linked immuno sorbent assay (ELISA) method. The developed method is suitable for an accurate, sensitive, and high-throughput screening of vitamin B 12 in energy drinks samples. The dipstick technique based on immuno-CL is suitable for the detection of several analyte in food and environmental samples. 相似文献
18.
An LC–UV screening method for simultaneous determination of ascorbic acid (C), and the free forms of thiamine (B1) riboflavin (B2), niacin (B3), pyridoxine (B6) in enriched food products was developed and validated. The chromatographic separation was accomplished within 18 min using a gradient of water with 0.1% formic acid (pH 2.5) and methanol with 0.1% formic acid on a C18 reverse phase column (5 μm, 150 × 3.2 mm) while detection was performed at two wavelengths (266 and 290 nm). Sample preparation was based on an extraction method originally developed for vitamin C. This procedure besides extracting vitamin C was extended to the extraction of the free forms of vitamins B1, B2, B3, B6 and B9. The developed analytical method was successfully applied for the simultaneous determination of the vitamin C content along with the free vitamin B forms of three different enriched food products. 相似文献
19.
An LC–UV screening method for simultaneous determination of ascorbic acid (C), and the free forms of thiamine (B 1) riboflavin (B 2), niacin (B 3), pyridoxine (B 6) in enriched food products was developed and validated. The chromatographic separation was accomplished within 18 min using a gradient of water with 0.1% formic acid (pH 2.5) and methanol with 0.1% formic acid on a C 18 reverse phase column (5 μm, 150 × 3.2 mm) while detection was performed at two wavelengths (266 and 290 nm). Sample preparation was based on an extraction method originally developed for vitamin C. This procedure besides extracting vitamin C was extended to the extraction of the free forms of vitamins B 1, B 2, B 3, B 6 and B 9. The developed analytical method was successfully applied for the simultaneous determination of the vitamin C content along with the free vitamin B forms of three different enriched food products. 相似文献
20.
In this paper is described the applicability of a flow injection system, operating with an amperometric detector, for measurement in rapid and simple way the antioxidant power of honey, propolis and royal jelly. The proposed method evaluates the reducing power of selected antioxidant compounds and does not require the use of free radicals or oxidants. Twelve honey, 12 propolis and 4 royal jelly samples of different botanical and geographical origin were evaluated by the electrochemical method and the data were compared with those obtained by the DPPH assay. Since a good correlation was found ( R2 = 0.92) the proposed electrochemical method can be successfully employed for the direct, rapid and simple monitoring of the antioxidant power of honeybee products. Furthermore, the total phenolic content of samples was determined by the Folin-Ciocalteau procedure and the characteristic antioxidant activities showed a good correlation with phenolics ( R2 = 0.96 for propolis and 0.90 for honey). 相似文献
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