scholarly journals Rapid and Specific Measurements of Superoxide Using Fluorescence Spectroscopy

2012 ◽  
Vol 18 (4) ◽  
pp. 498-503 ◽  
Author(s):  
Rafal R. Nazarewicz ◽  
Alfiya Bikineyeva ◽  
Sergey I. Dikalov
Keyword(s):  
Superoxide Dismutase ◽  
Fluorescence Spectroscopy ◽  
High Performance ◽  
Hplc Analysis ◽  
Cultured Cells ◽  
Oxidation Products ◽  
Specific Detection ◽  
Intact Cells ◽  
Specific Product ◽  
Plate Reader

Superoxide plays a key role in many pathological processes; however, detection of superoxide by one of the most common methods using dihydroethidium (DHE) may be unspecific because of overlapping fluorescence of the superoxide-specific product, 2-OH-ethidium (2OH-E), and the unspecific oxidation product, ethidium. Here, we show a new optimized fluorescence spectroscopy protocol that allows rapid and specific detection of superoxide in cell-free systems and intact cells using DHE. We defined new optimized fluorescent settings to measure the superoxide-specific product and minimize the interference of unspecific DHE oxidation products. Using this protocol, we studied real-time superoxide production by xanthine oxidase– and menadione-treated cultured cells. Specificity of the plate reader–based superoxide measurements was confirmed by the inhibition of fluorescence with superoxide dismutase and high-performance liquid chromatography (HPLC) analysis. We show that limitations of the HPLC-based analysis can be overcome by the optimized fluorescence spectroscopy.

The Dtermination of Paracetamol by HPLC Validation of the Method and Application on Serum Samples

2018 ◽  
Vol 69 (3) ◽  
pp. 627-631 ◽  
Author(s):  
Viorica Ohriac (Popa) ◽  
Diana Cimpoesu ◽  
Adrian Florin Spac ◽  
Paul Nedelea ◽  
Voichita Lazureanu ◽  
...  
Keyword(s):  
Mobile Phase ◽  
High Performance ◽  
Hplc Analysis ◽  
Emotional Experience ◽  
Optimum Conditions ◽  
Serum Samples ◽  
Liquid Chromatograph ◽  
Mobile Phase Flow Rate ◽  
Quantification Limit

Pain is defined as a disagreeable sensory and emotional experience related to a tissue or potential lesion. Paracetamol (Acetaminophen) is the most used non-morphine analgesic. For the determination of paracetamol we developed and validated the high performance liquid chromatography (HPLC) analysis using a Dionex Ultimate 3000 liquid chromatograph equipped with a multidimensional detector. After determining the optimum conditions of analysis (80/20 water / acetonitrile mobile phase, flow rate 1.0 mL / min, detection wavelength 245 nm) we validated the method following the following parameters: linearity of response function, linearity of results, limit (LD = 0.66 mg / mL) and quantification limit (LQ = 2.00 mg / mL), and precision. The method of determining paracetamol by HPLC was applied to 30 samples of serum collected from patients who had pain and were treated with paracetamol.

scholarly journals Simple HPLC-PDA Analysis to Determine Illegal Synthetic Dyes in Herbal Medicines

2021 ◽  
Vol 11 (14) ◽  
pp. 6641
Author(s):  
Kyung-Yuk Ko ◽  
Eun-Young Choi ◽  
Se-Hee Jeong ◽  
Sohwa Kim ◽  
Choon-Kil Lee ◽  
...  
Keyword(s):  
High Performance ◽  
Hplc Analysis ◽  
Ammonium Acetate ◽  
Herbal Medicines ◽  
Positive Sample ◽  
Array Detector ◽  
Synthetic Dyes ◽  
Sunset Yellow ◽  
Herbal Medication ◽  
Relative Standard

Various synthetic dyes are artificially added to herbal medicines for the purpose of visual attraction. In order to monitor the illegal usage of synthetic dyes in herbal medication, a rapid and straightforward analysis method to determine synthetic dyes is required. The study aimed to develop and validate a high-performance liquid chromatography (HPLC) analysis to determine ten synthetic dyes in Hawthorn fruit, Cornus fruit, and Schisandra fruit. Ten synthetic dyes such as Tartrazine, Sunset yellow, Metanil yellow, Auramine O, Amaranth, Orange II, Acid red 73, Amaranth, New Coccine, Azorubine, and Erythrosine B, were extracted using 50 mM ammonium acetate in 70% MeOH; then separated by gradient elution with a mobile phase consisting of acetonitrile and 50 mM ammonium acetate in distilled water using a photodiode array detector (PDA) at 428 nm or 500 nm. In addition, this study established the LC-MS/MS method to confirm the existence of synthetic dyes in the positive sample solution. The HPLC analysis had good linearity (r2 > 0.999). The recoveries of this method ranged from 74.6~132.1%, and the relative standard deviation (RSD) values were less than 6.9%. Most of the samples fulfilled the acceptance criteria of the AOAC guideline. This study demonstrates that the HPLC analysis can be applied to determine ten synthetic dyes in herbal medication.

HPLC Analysis of Oxytetracycline Residues in Honey

1986 ◽  
Vol 49 (5) ◽  
pp. 383-388 ◽  
Author(s):  
PETER SPORNS ◽  
SUET KWAN ◽  
LAWRENCE A. ROTH
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Aqueous Solutions ◽  
High Performance ◽  
Hplc Analysis ◽  
Extraction Procedure ◽  
Hplc Method ◽  
Limits Of Detection ◽  
Ph Values ◽  
Double Extraction

Oxytetracycline (OTC), also known commercially as Terramycin, was determined to be more stable in honey than in buffered aqueous solutions at similar pH values and temperatures. A rapid high performance liquid chromatography (HPLC) method was developed to detect and quantitate OTC using a 1:1 dilution (wt/wt) of honey samples in water. Using 355 nm as the wavelength of detection, amounts as low as 0.5 μg/ml could be detected in the above solution. The limits of detection were lowered considerably by a double extraction procedure.

scholarly journals Determination of amino acids in human biological fluids by high-performance liquid chromatography: critical review

Amino Acids ◽  
2021 ◽  
Author(s):  
Grażyna Gałęzowska ◽  
Joanna Ratajczyk ◽  
Lidia Wolska
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
High Performance ◽  
Hplc Analysis ◽  
Limit Of Detection ◽  
Biological Fluids ◽  
Analytical Techniques ◽  
Epidemiological Studies ◽  
Preparation Conditions

AbstractThe quantitation and qualification of amino acids are most commonly used in clinical and epidemiological studies, and provide an excellent way of monitoring compounds in human fluids which have not been monitored previously, to prevent some diseases. Because of this, it is not surprising that scientific interest in evaluating these compounds has resurfaced in recent years and has precipitated the development of a multitude of new analytical techniques. This review considers recent developments in HPLC analytics on the basis of publications from the last few years. It helps to update and systematize knowledge in this area. Particular attention is paid to the progress of analytical methods, pointing out the advantages and drawbacks of the various techniques used for the preparation, separation and determination of amino acids. Depending on the type of sample, the preparation conditions for HPLC analysis change. For this reason, the review has focused on three types of samples, namely urine, blood and cerebrospinal fluid. Despite time-consuming sample preparation before HPLC analysis, an additional derivatization technique should be used, depending on the detection technique used. There are proposals for columns that are specially modified for amino acid separation without derivatization, but the limit of detection of the substance is less beneficial. In view of the fact that amino acid analyses have been performed for years and new solutions may generate increased costs, it may turn out that older proposals are much more advantageous.

Impurities from polypropylene microcentrifuge tubes as a potential source of interference in simultaneous analysis of multiple lipid-soluble antioxidants by HPLC with electrochemical detection

2004 ◽  
Vol 42 (4) ◽  
Author(s):  
Hsiu-Chuan Yen ◽  
Yi-Tzu Hsu
Keyword(s):  
High Performance Liquid Chromatography ◽  
Electrochemical Detection ◽  
High Performance ◽  
Hplc Analysis ◽  
Coenzyme Q ◽  
Retinyl Palmitate ◽  
Plasma Samples ◽  
Potential Source ◽  
Effect Of Impurities ◽  
Β Carotene

AbstractHigh-performance liquid chromatography (HPLC) with electrochemical detection was used to analyze lipidsoluble antioxidants and micronutrients in plasma. Small amounts of plasma samples are often extracted in polypropylene (PP) microcentrifuge tubes before HPLC analysis due to its convenience. We therefore investigated the effect of impurities released from different PP tubes during extraction on the electrochemical detection of retinol, lutein, α-tocopherol, γ-tocopherol, retinyl palmitate, β-carotene and total coenzyme Q

scholarly journals Production of free radicals by the Co2+/Oxone system to carry out diclofenac degradation in aqueous medium

2018 ◽  
Vol 78 (10) ◽  
pp. 2131-2140 ◽  
Author(s):  
Oscar M. Rodríguez-Narváez ◽  
Oracio Serrano-Torres ◽  
Kazimierz Wrobel ◽  
Enric Brillas ◽  
Juan M. Peralta-Hernandez
Keyword(s):  
Free Radicals ◽  
High Performance ◽  
Hplc Analysis ◽  
Apparent Rate Constant ◽  
Oxygen Demand ◽  
Co2 Concentration ◽  
Oh Radicals ◽  
Order Kinetic ◽  
Kinetic Reaction ◽  
Ion Exclusion

Abstract This paper reports the degradation of a solution of 0.314 mM diclofenac (DCF), while using 5–15 mM Oxone as oxidizing agent with the catalytic action of 0.05–0.2 mM Co2+. The best performance was obtained for 10 mM Oxone and 0.2 mM Co2+, achieving the total DCF abatement and 77% removal of chemical oxygen demand after 30 min. Oxidizing of sulfate () and hydroxyl (•OH) radicals was formed by the Co2+/Oxone system. Oxone was firstly oxidized to persulfate ion that was then quickly converted into the above free radicals. For Oxone contents ≥10 mM, the decay of DCF concentration followed a second-order kinetic reaction, but the apparent rate constant changed with the Co2+ concentration used. High-performance liquid chromatography (HPLC) analysis of treated solutions showed the formation of some intermediates, whereas oxalic acid was identified as the prevalent final short-linear carboxylic acid by ion-exclusion HPLC.

scholarly journals Health benefits of new symbiotic “NAR”

2014 ◽  
Vol 2 ◽  
Author(s):  
Saule Saduakhasova ◽  
Almagul Kushugulova ◽  
Samat Kozhakhmetov ◽  
Gulnara Shakhabayeva ◽  
Adil Supiyev ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Superoxide Dismutase ◽  
Glutathione Reductase ◽  
Inflammatory Mediators ◽  
Antioxidant Activities ◽  
Reductase Activity ◽  
Protein A ◽  
Intact Cells ◽  
Total Antioxidant

Introduction: The immune-modulatory effects of synbiotics and their ability to reduce free radical levels may be useful for functional food that is able to be active throughout whole period of colonization of the gastrointestinal tract.The aim of the present study was to investigate the immune-modulatory and antioxidant effects of the synbiotic product "NАR," a probiotic beverage.Methods: The presence of IL-2, IL-4, IL-6, IL-8, IL-10, αTNF, γIFN, Ig A, Ig M, and Ig E was studied in vitro using a solid immunosorbent analysis. The total antioxidant activities of superoxide dismutase and glutathione reductase were determined by a spectrophotometry using the Sigma-Aldrich sets.Results: Studies of the immune-modulatory properties of the synbiotic product NAR showed 1.7 fold increase of γINF levels (p<0.01) in blood after consumption of the synbiotic product “NAR” in comparison to control values, whereas the concentrations of IL-4 and Ig E decreased 2.0 times (treatment: 9.3; control: 18.7; p<0.01) and 1.3 times (p<0.1), respectively. The consumption of the synbiotic product “NAR” caused an increase in the proportion of γINF/IL 4 (treatment: 15.4; control: 4.4; p<0.01), which indicates a reduction in functional activity of Th2-type lymphocytes in comparison with the function of Th1 cells.Our study showed a high level of the total antioxidant activity of the synbiotic product (67.4 mmol/ml). The antioxidant activity of the intact cells of consortium (15.3 mM/ml), which was the basis for the preparation of the symbiotic product, is several times lower than the activity observed in the symbiotic samples.Expression of SOD is one of the mechanisms of antioxidant stress radicals inactivation by bacteria. The analysis identified a superoxide dismutase activity of synbiotic product (1.42 U/mg protein). A glutathione reductase activity of the synbiotic product was elevated (0.06 U/ml). Conclusion: The majority of the inflammatory mediators found in the blood after the consumption of symbiotic product NAR were inflammatory mediators that activate a cellular component of the resistance. Moreover, the symbiotic product has a high antioxidant activity. 

ANTHOCYANIN, AGLYCONE AND AGLYCONE-SUGAR CONTENT OF FRUITS OF TEMPERATE NORTH AMERICAN SPECIES OF Gaylussacia (ERICACEAE)

1988 ◽  
Vol 68 (1) ◽  
pp. 247-253 ◽  
Author(s):  
J. R. BALLINGTON ◽  
W. E. BALLINGER ◽  
E. P. MANESS
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
North American ◽  
High Performance ◽  
Hplc Analysis ◽  
Sugar Content ◽  
North American Species ◽  
The Other ◽  
Phylogenetic Implications

HPLC analysis of the true huckleberry species Gaylussacia baccata, G. dumosa, G. frondosa, G. mosieri, and G. ursina identified the 3-monoarabinosides, 3-monogalactosides, and 3-monoglucosides of cyanidin, delphinidin, malvidin, peonidin, and petunidin. Gaylussacia brachycera contained all anthocyanins, except peonidin-3-arabinoside. Gaylussacia brachycera differed from other species in percent delphinidin-3-arabinoside. It was higher than the other species in percent of the aglycone delphinidin and lower in cyanidin, and also higher in percent of the sugar arabinose. There were no detectable differences among the other species for anthocyanins, aglycones, or aglycone-sugars. The phylogenetic implications of the similarities among species of Gaylussacia and Vaccinium in anthocyanins, aglycones, and aglycone-sugars of the fruit were discussed.Key words: High-performance liquid chromatography, huckleberries, blueberries, chemotaxonomy, taxonomy, biosystematics

scholarly journals Forskolin refractoriness. Exposure to the diterpene alters guanine nucleotide-dependent adenylate cyclase and calcium-uptake activity of cells cultured from the rat aorta

1987 ◽  
Vol 241 (2) ◽  
pp. 463-467 ◽  
Author(s):  
J F Krall ◽  
N Jamgotchian
Keyword(s):  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Cultured Cells ◽  
Rat Aorta ◽  
Cyclase Activity ◽  
Adenylate Cyclase Activity ◽  
Morphological Properties ◽  
Guanine Nucleotide ◽  
Intact Cells ◽  
Uptake Activity

Cells with the morphological properties of endothelial cells were cultured from the rat aorta. The cultured cells accumulated 45Ca2+ from the medium in a manner which was stimulated by forskolin and by 8-bromo-cyclic AMP. Pretreating the cultures for 20 h with forskolin diminished forskolin-dependent Ca2+-uptake activity. Adenylate cyclase activity of cultured cell homogenates was stimulated by guanosine 5′-[beta, gamma-imido]triphosphate (p[NH]ppG) and forskolin, and by isoprenaline in the presence, but not in the absence, of guanine nucleotide. p[NH]ppG increased forskolin sensitivity and caused a leftward shift in the forskolin dose-response curve. Pretreating the cultured cells with forskolin for 20 h, conditions that decreased forskolin-dependent Ca2+ uptake, increased basal and guanine nucleotide-dependent adenylate cyclase activity, but not forskolin-dependent activity determined in the absence of p[NH]ppG. Forskolin pretreatment diminished p[NH]ppG's capacity to increase forskolin sensitivity, but did not have a significant effect on either the sensitivity of adenylate cyclase to p[NH]ppG or its responsiveness to isoprenaline. These results suggest that the Ca2+-uptake mechanism is cyclic AMP-dependent and that guanine nucleotides mediated forskolin-dependent cyclic AMP production by the intact cells. In addition, there may be different guanine nucleotide requirements for hormone-receptor coupling and forskolin activation.

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