Analysis of the main conjugated linoleic acid (CLA) precursors (C18:2 n-6 and C18:3 n-3) in Brachiaria ruzizienses by capillary zone electrophoresis

AbstractAn alternative method for extraction optimization of C18:2 n-6 and C18:3 n-3, the main precursors for the synthesis of conjugated linoleic acid (CLA), in Brachiaria ruzizienses forages was proposed. Three methods of lipid extraction were tested: 1. Hara & Radin, 2. Micro Folch and 3. Bligh & Dyer. The preliminary test showed the Hara & Radin method as the most promising procedure. Then, a 33 Box Behnken design with triplicate in the central point was applied in Hara & Radin method in order to optimize the extraction procedure. The optimization extraction was monitored by quantification of C18:2 n-6 and C18:3 n-3 through capillary zone electrophoresis (CZE). The results obtained by CZE were compared to gas chromatography (AOCS official method) in real samples using the paired t-test. No significant difference between methods was found within a 95% confidence interval (p-value= 0.937). The alternative CZE method for Brachiaria ruzizienses forages analysis has some advantages in comparison with official GC method such as, short analysis time (10 min), no derivatization step for sample preparation, absence of specific separation columns, lower analytical cost and high throughput.

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A Rapid Method for Determination of the Main Conjugated Linoleic Acid Precursors (C18:2 n-6 and C18:3 n-3) in Forage by Capillary Zone Electrophoresis with Ultraviolet Detection Using Gas Chromatography with Flame Ionization Detection as a Comparative Method

Journal of AOAC International ◽

10.5740/jaoacint.15-076 ◽

2015 ◽

Vol 98 (6) ◽

pp. 1591-1597

Author(s):

Renata de Jesus Coelho Castro ◽

Fausto Souza Sobrinho ◽

Marco Antônio Sundfeld da Gama ◽

Renata Takabayashi Sato ◽

Larissa Lavorato Lima ◽

...

Keyword(s):

Linoleic Acid ◽

Conjugated Linoleic Acid ◽

Rapid Method ◽

Capillary Zone Electrophoresis ◽

Official Method ◽

Improvement Program ◽

Flame Ionization ◽

Zone Electrophoresis ◽

Capillary Zone

Abstract A rapid method has been proposed for determination of the main conjugated linoleic acid precursors such as linoleic (C18:2 n-6) and linolenic (C18:3 n-3) acids in forages by capillary zone electrophoresis (CZE) with direct UV detection at 200 nm. Among the fatty acids found in forages, C18:2 n-6 and C18:3 n-3 have received particular attention due to their roles as precursors for the synthesis of conjugated linoleic acid, a class of health-enhancing compounds that is predominantly found in dairy products. The electrolyte background consisted of 12.0 mmol/L tetraborate buffer (pH 9.2) added to 12.0 mmol/L Brij 35®, 17% acetonitrile, and 33% methanol. Under the optimized conditions, the baseline separation of C18:2 n-6 and C18:3 n-3 was achieved within 4 min. The CZE-UV method was compared to GC with a flame ionization detector, which is the American Oil Chemists' Society (AOCS 996.06) official method for fatty acid analysis. The methods did not show any evidence of significant differences within 95% confidence interval (P > 0.05). The CZE-UV method was successfully applied to the analysis of 80 genotypes of Brachiaria ruzizienses clones submitted to a genetic improvement program in agricultural research.

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Simultaneous Determination of Sitagliptin and Metformin in Pharmaceutical Preparations by Capillary Zone Electrophoresis and its Application to Human Plasma Analysis

Analytical Chemistry Insights ◽

10.4137/aci.s9940 ◽

2012 ◽

Vol 7 ◽

pp. ACI.S9940 ◽

Cited By ~ 25

Author(s):

Mohamed Salim ◽

Nahed El-Enany ◽

Fathallah Belal ◽

Mohamed Walash ◽

Gabor Patonay

Keyword(s):

Simultaneous Determination ◽

Human Plasma ◽

Capillary Zone Electrophoresis ◽

Pharmaceutical Preparations ◽

Effective Length ◽

Relative Standard ◽

Significant Difference ◽

Zone Electrophoresis ◽

Capillary Zone

A novel, quick, reliable and simple capillary zone electrophoresis CZE method was developed and validated for the simultaneous determination of sitagliptin (SG) and metformin (MF) in pharmaceutical preparations. Separation was carried out in fused silica capillary (50.0 cm total length and 43.0 cm effective length, 49 μm i.d.) by applying a potential of 15 KV (positive polarity) and a running buffer containing 60 mM phosphate buffer at pH 4.0 with UV detection at 203 nm. The samples were injected hydrodynamically for 3 s at 0.5 psi and the temperature of the capillary cartridge was kept at 25 °C. Phenformin was used as internal standard (IS). The method was suitably validated with respect to specificity, linearity, limit of detection and quantitation, accuracy, precision, and robustness. The method showed good linearity in the ranges of 10-100 μg/mL and 50-500 μg/mL with limits of detection of 0.49, 2.11 μm/mL and limits of quantification of 1.48, 6.39 μg/mL for SG and MF, respectively. The proposed method was successfully applied for the analysis of the studied drugs in their synthetic mixtures and co-formulated tablets without interfering peaks due to the excipients present in the pharmaceutical tablets. The method was further extended to the in-vitro determination of the two drugs in spiked human plasma. The estimated amounts of SG/MF were almost identical with the certified values, and their percentage relative standard deviation values (% R.S.D.) were found to be ≤1.50% (n = 3). The results were compared to a reference method reported in the literature and no significant difference was found statistically.

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Simultaneous analysis of first-line anti-tuberculosis drugs in tablets by UV spectrophotometry compared to capillary zone electrophoresis

Open Chemistry ◽

10.2478/s11532-012-0102-6 ◽

2012 ◽

Vol 10 (6) ◽

pp. 1808-1816 ◽

Cited By ~ 2

Author(s):

Luiza Marcellos ◽

Adriana Faria ◽

Marcus Souza ◽

Mariana Almeida ◽

Guilherme Sabin ◽

...

Keyword(s):

Capillary Zone Electrophoresis ◽

Latent Variables ◽

Multivariate Calibration ◽

Least Squares Method ◽

Simultaneous Analysis ◽

Fixed Dose ◽

Uv Spectrophotometry ◽

Significant Difference ◽

Zone Electrophoresis ◽

Capillary Zone

AbstractThe development and optimization of a novel UV spectrophotometric methodology was proposed for simultaneous analysis of ethambutol (ETB), isoniazid (ISO), rifampicin (RIF) and pyrazinamide (PYR), using multivariate calibration based on the partial least squares method (PLS). The methodology was successfully applied for analysis of four-drug fixed dose combination (4-FDC) tablets used for tuberculosis treatment. A 34 Box-Behnken design, with triplicate in central point, was used for sample preparation in the calibration step. In the present case, nine latent variables were chosen for the model development that presented the smallest RMSECV and explain 98.76% of data variance in Y block (concentrations of ETB ISO, RIF and PYR) and 99.93% of data variance in X block (spectral data). PLS models for ETB, ISO, RIF and PYR presented RMSEP and R2 values of 0.23 mg L−1 and 0.971; 0.14 mg L−1 and 0.731; 0.11 mg L−1 and 0.990 and 0.57 mg L−1 and 0.972, respectively. A validation step was performed based on the comparison between the UV spectrophotometric proposed methodology and capillary zone electrophoresis (CZE) in 4-FDC real samples and no significant difference was found between two methodologies at 95% of confidence level.

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A NEW CAPILLARY ZONE ELECTROPHORESIS METHOD FOR THE SCREENING OF CONGENITAL DISORDERS OF GLYCOSYLATION (CDG)

Clinical & Investigative Medicine ◽

10.25011/cim.v32i6s.11144 ◽

2009 ◽

Vol 32 (6S) ◽

pp. 7

Author(s):

F Parente ◽

N Ah Mew ◽

J Jaeken ◽

B M Gilfix

Keyword(s):

Capillary Zone Electrophoresis ◽

Metabolic Diseases ◽

Clinical Syndrome ◽

Congenital Disorders ◽

Congenital Disorders Of Glycosylation ◽

Serum Samples ◽

Significant Difference ◽

Zone Electrophoresis ◽

Capillary Zone ◽

Guthrie Cards

Background: The Congenital Disorders of Glycosylation (CDG) are an expanding group of metabolic diseases with a broad clinical presentation. We sought to validate a new Capillary Zone Electrophoresis (CZE) method (Sebia CAPILLARYS™ CDT) to screen for CDG. Methods: We analyzed 119 serum samples from children of varying ages and of both sexes to establish a reference range of transferrin glycoforms including CDT (Carbohydrate Deficient Transferrin). We then studied serums from 8 known CDG patients and compared the CZE results to the isoelectric focusing (IEF) profiles. We also analyzed serums after extraction from spotted Guthrie cards. Results: The mean (SD) percentage of transferrin glycoforms is 18.5 (4.4), 78.5 (4.2), 2.5 (1.3) and 0.6 (0.3) for penta-, tetra-, trisialotransferrin and CDT, respectively. There is no statistically significant difference between the different age groups analyzed (0-5, 6-11, 12-15, 16-18, and > 18 years) or between sexes. We observed a good correlation between the CZE and IEF profiles with both fresh serum and serum extracted from Guthrie cards. Conclusions: The Sebia CAPILLARYS™ CDT system is a simple and reliable method to screen for CDG in pediatric and adult patients with an unexplained clinical syndrome, particularly when the nervous system is involved.

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The non-destructive separation of diverse astrobiologically relevant organic molecules by customizable capillary zone electrophoresis and monolithic capillary electrochromatography

International Journal of Astrobiology ◽

10.1017/s1473550419000065 ◽

2019 ◽

Vol 18 (6) ◽

pp. 562-574

Author(s):

Kosuke Fujishima ◽

Szymon Dziomba ◽

Hajime Yano ◽

Seydina I. Kebe ◽

Mohamed Guerrouache ◽

...

Keyword(s):

Capillary Zone Electrophoresis ◽

Capillary Electrochromatography ◽

Organic Molecules ◽

Extraction Procedure ◽

Building Blocks ◽

Hypervelocity Impact ◽

Analytical Strategy ◽

Zone Electrophoresis ◽

Capillary Zone ◽

The Impact

AbstractThe in situ detection of organic molecules in space is key to understanding the variety and the distribution of the building blocks of life, and possibly the detection of extraterrestrial life itself. Gas chromatography mass spectrometry (GC-MS) has been the most sensitive analytical strategy for organic analyses in flight, and was used on missions from NASA's Viking, Phoenix, Curiosity missions to ESA's Rosetta space probe. While pyrolysis GC-MS revealed the first organics on Mars, this step alters or degrades certain fragile molecules that are excellent biosignatures including polypeptides, oligonucleotides and polysaccharides, rendering the intact precursors undetectable. We have identified a solution tailored to the detection of biopolymers and other biomarkers by the use of liquid-based capillary electrophoresis and electrochromatography. In this study, we show that a capillary electrochromatography approach using monolithic stationary phases with tailor-made surface chemistry can separate and identify various polycyclic aromatic hydrocarbons, nucleobases and aromatic acids that could be formed under astrophysically relevant conditions. In order to simulate flyby organic sample capture, we conducted hypervelocity impact experiments which consisted of accelerating peptide-soaked montmorillonite particles to a speed of 5.6 km s−1, and capturing them in an amorphous silica aerogel of 10 mg cm−3 bulk density. Bulk peptide extraction from aerogel followed by capillary zone electrophoresis led to the detection of only two stereoisomeric peptide peaks. The recovery rates of each step of the extraction procedure after the hypervelocity impact suggest that major peptide loss occurred during the impact. Our study provides initial exploration of feasibility of this approach for capturing intact peptides, and subsequently detecting candidate biomolecules during flight missions that would be missed by GC-MS alone. As the monolith-based electrochromatography technology could be customized to detect specific classes of compounds as well as miniaturized, these results demonstrate the potential of the instrumentation for future astrobiology-related spaceflight missions.

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