Capillary electrophoresis of wheat gliadin proteins and its potential for wheat varietal identification using pattern matching software

Gliadins from 11 wheat flours were extracted with 30% ethanol and fractionated by capillary electrophoresis on a 20-µm i.d. untreated fused silica capillary using 0.1 M phosphate buffer (pH 2.5) containing polymer modifier. Capillary electrophoresis conducted at a constant current provided very good resolution and reproducibility (relative standard deviation <0.5) in mp;lt;15 min. Pattern matching of the profiles was performed with the PatMatch program to provide quantitative comparisons, using the relative mobility and intensity data for each gliadin protein. Data processing parameters, including the integration of the electrophoregram, were optimised for separation of gliadins extracted from either whole-grain or flour samples. The reproducibility and repeatability were compared using peak height and/or area percentages. The optimal window width for identifying matching gliadin peaks was 0.80–1.20% relative mobility units. Using these conditions, it was concluded that unknown varieties could be identified with a confidence level of 90–95%.

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Analysis of Synthetic Antioxidant in Food by Capillary Electrophoresis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.361-363.1855 ◽

2011 ◽

Vol 361-363 ◽

pp. 1855-1858 ◽

Cited By ~ 1

Author(s):

Qian Xiang ◽

Ying Gao

Keyword(s):

Capillary Electrophoresis ◽

Amperometric Detection ◽

Peak Height ◽

Butylated Hydroxyanisole ◽

Applied Potential ◽

Synthetic Antioxidant ◽

Separation Potential ◽

Relative Standard ◽

Capillary Electrophoretic

A capillary electrophoretic assay for determining synthetic antioxidant butylated hydroxyanisole in food has been developed. The extraction with 70% (v/v) methanol quantitatively extracted synthetic antioxidant. The separation was carried out by CZE using phosphate at a separation potential of 18 kV. Amperometric detection was achieved with an applied potential of 0.60 V. A linear relationship between the peak height and the concentration of the analyte was found in the range 1.8-180 µg/mL for BHA, with correlation coefﬁcient of 0.994. The relative standard deviations of migration time and peak height were 0.19 and 5.3 %, respectively. The method developed was successfully applied for the determination of synthetic antioxidant butylated hydroxyanisole in food. Recovery of butylated hydroxyanisole was 93%.

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Development of a Capillary Electrophoresis Method for the Enantioselective Estimation of Primaquine in Pharmaceutical Formulations

Journal of AOAC International ◽

10.1093/jaoac/91.3.536 ◽

2008 ◽

Vol 91 (3) ◽

pp. 536-541 ◽

Cited By ~ 1

Author(s):

Abdalla A Elbashir ◽

Bahruddin Saad ◽

Abdussalam Salhin Mohamed Ali ◽

Muhammad Idiris Saleh

Keyword(s):

Capillary Electrophoresis ◽

Applied Voltage ◽

Pharmaceutical Formulations ◽

Fused Silica ◽

Chiral Selector ◽

Effective Length ◽

Racemic Mixture ◽

Injection Time ◽

Relative Standard ◽

Capillary Temperature

Abstract A capillary electrophoresis (CE) method has been developed that allows the separation and estimation of primaquine enantiomers using hydroxypropyl--cyclodextrin (HP--CD) as a chiral selector. The influence of chemical and instrumental parameters on the separation, such as type and concentration of CD, buffer concentration, buffer pH, applied voltage, capillary temperature, and injection time, were investigated. Good separation of the racemic mixture of primaquine was achieved using a fused-silica capillary (52.5 cm effective length 50 m id) and a background electrolyte composed of tris-phosphate buffer solution (50 mM, pH 2.5) containing 15 mM HP--CD as a chiral selector. The recommended applied voltage, capillary temperature, and injection time were 15 kV, 25C, and 6 s, respectively. Within-day and interday reproducibility of peak area and migration time gave relative standard deviation values ranging from 1.053.30. Good recoveries (range of 96.8104.9) were obtained from the determination of placebos that were spiked with 0.251.00 mg/L primaquine. The proposed CE method was successfully applied to the assay of primaquine diphosphate in pharmaceutical formulations (tablets).

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A Friendly Environmental CE Method to Determine Doxycycline Hyclate in Suppositories and Application to Tablet Assay

Current Analytical Chemistry ◽

10.2174/1573411014666180131162033 ◽

2019 ◽

Vol 15 (5) ◽

pp. 531-539 ◽

Cited By ~ 1

Author(s):

Ana P. Christ ◽

Sulen L. Burin ◽

Andréa I.H. Adams

Keyword(s):

Degradation Products ◽

Fused Silica ◽

Effective Length ◽

Official Method ◽

Good Resolution ◽

Doxycycline Hyclate ◽

Related Substance ◽

Relative Standard ◽

Fused Silica Capillary ◽

Electrophoresis Method

Background: The demand for green analytical methods is rising, mainly due its impact on the reduction of waste generation. The official method to assay Doxycycline Hiclate (DOXH) is HPLC, using an unusual column and a multi-component mobile phase. Objective: To develop a capillary electrophoresis method (CZE) to assay DOXH in suppositories and tablets. Methods: Doxycycline was analyzed in a CZE system using a fused silica capillary silica (effective length 40 cm), voltage 25kV, temperature 24°C, detection at 260 nm and hydrodynamic injection of 50mBar/5s. The electrolyte was a mixture of acetonitrile and aqueous solution composed of 25 mM sodium carbonate and 5mM EDTA, pH 10.6. Results: The method was validated according to ICH requirements and DOXH detection was achieved at around 5 min. A linear relationship was observed in the range of 20 to 160 µg.mL-1, the method was precise, showing values of relative standard deviation below 2%. Accuracy was demonstrated by DOXH recovery values ranging from 98.0 to 102.0%, for all the formulations. The specificity was studied by the peak purity evaluation and by the good resolution between peaks of DOXH, degradation products and a related substance intentionally added to the sample solution. Robustness was evaluated by 23 full factorial design, and no effect on DOXH assay was observed under simultaneous variation in significant analytical parameters. Conclusion: This simple and inexpensive method may be used to determine DOXH in suppositories as well tablets, under identical analytical conditions and can be a green alternative to the HPLC official method.

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Capillary Electrophoresis Method for Fexofenadine Hydrochloride in Capsules

Journal of AOAC International ◽

10.1093/jaoac/88.4.1059 ◽

2005 ◽

Vol 88 (4) ◽

pp. 1059-1063 ◽

Cited By ~ 14

Author(s):

Ana R Breier ◽

Sílvia S Garcia ◽

André Jablonski ◽

Martin Steppe ◽

Elfrides E S Schapoval

Keyword(s):

Capillary Electrophoresis ◽

Potential Temperature ◽

Fused Silica ◽

System Control ◽

Chromatography Method ◽

Limits Of Detection ◽

Capillary Electrophoresis Method ◽

Relative Standard ◽

Significant Difference ◽

Electrophoresis Method

Abstract A simple, accurate, and effective capillary electrophoresis method with ultraviolet absorbance detection was developed and validated for the quantitation of the antihistamine fexofenadine in capsules. The separation was performed with an uncoated fused-silica capillary (47 cm × 75 μm id) and was operated at 20 kV potential. Temperature was maintained at 25°C. The run buffer was prepared with 20mM Na2B4O7 × 10 H2O. Software was used for system control, data acquisition, and analysis. Method validation was performed by evaluation of the analytical parameters linearity, precision, accuracy, limits of detection and quantitation, and specificity. The method was linear (r = 0.9999) at concentrations ranging from 20 to 100 μg/mL, precise (relative standard deviation intra-assay = 1.2, 1.6, and 1.8% and interassay = 1.5%); accurate (recovery = 98.1%); and specific. The limits of detection and quantitation were 0.69 and 2.09 μg/mL, respectively. The method was compared to the liquid chromatography method developed previously by the authors for the same drug, and no significant difference was found between the 2 methods in fexofenadine hydrochloride quantitation.

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Validation of a Capillary Electrophoresis Method for Analysis of Rabeprazole Sodium in a Pharmaceutical Dosage Form

Journal of AOAC International ◽

10.1093/jaoac/88.4.1081 ◽

2005 ◽

Vol 88 (4) ◽

pp. 1081-1085 ◽

Cited By ~ 11

Author(s):

Cássia V Garcia ◽

Juliana Sippel ◽

Leticia L Sfair ◽

Silvia S Garcia ◽

André Jablonski ◽

...

Keyword(s):

Capillary Electrophoresis ◽

Fused Silica ◽

Array Detector ◽

System Control ◽

Fast Analysis ◽

Pharmaceutical Dosage Form ◽

Capillary Electrophoresis Method ◽

Relative Standard ◽

Rabeprazole Sodium ◽

Electrophoresis Method

Abstract Rabeprazole sodium is an antisecretory agent that inhibits the enzyme H+/K+ ATPase present in the stomach parietal cells. There are few data about its quantitative determinations in laboratorial routines. Capillary electrophoresis is a method being used increasingly for analysis of pharmaceutical compounds, the main advantages of which are the simplicity of instrumentation, low consumption of sample and reagents, and fast analysis. The aim of this study was to develop and validate a capillary electrophoresis method for determination of rabeprazole sodium in coated tablets. The conditions used were a bare fused silica capillary with 48.0 cm length (39.5 cm effective) and 75 μm id; a 10mM, pH 9.0, sodium tetraborate run buffer; a diode array detector set at 291 nm; hydrodynamic injection (50 mbar/5 s); and a voltage of 20 kV. HP Chemstation CE rev. A.06.03 software was used for system control, data acquisition, and analysis. The method was demonstrated to be linear in the concentration range of 5.0–40.0 μg/mL (r = 0.9993), precise (interday relative standard deviation = 0.49), accurate (mean recovery = 103.1%), and specific. The limits of detection and quantitation were 1.29 and 3.91 μg/mL, respectively.

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The determination of coumestrol in alfalfa (Medicago sativa) by capillary electrophoresis

Plant Soil and Environment ◽

10.17221/4230-pse ◽

2011 ◽

Vol 48 (No. 5) ◽

pp. 224-229 ◽

Cited By ~ 1

Author(s):

J. Moravcová ◽

T. Kleinová ◽

R. Loučka

Keyword(s):

Capillary Electrophoresis ◽

High Performance ◽

Solid Phase ◽

Internal Standard ◽

Fused Silica ◽

Detector Response ◽

Acid Extraction ◽

Relative Standard ◽

Fused Silica Capillary

High performance capillary electrophoresis (HPCE) on an uncoated fused-silica capillary column using a borate buffer at pH 9.2 as electrolyte and diode-array detection was developed for the determination of coumestrol in alfalfa. The linear detector response was established in the concentration range 0.76–140 mg.dm–3, the minimum detectable limit was 0.39 mg.dm–3, and migration time of coumestrol was 5 min. 3-Isobutyl-1-methylxanthin was used as an internal standard. Coumestrol was isolated by acid extraction employing a mixture hydrochloric acid-acetonitrile at 95°C for 30 min followed by solid phase extraction. Relative standard deviations of reproducibility and repeatability were 1.77% and 5.49%, respectively. Spiking recovery value of 92% was achieved. Alfalfa, variety Morava, contains 148–248 mg.kg–1 coumestrol in dry matter. The proposed method is useful for routine analyses.

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Validated Stability Indicating HPTLC Method for the Estimation of Amoxapine in Different Stress Conditions

Current Pharmaceutical Analysis ◽

10.2174/1573412914666171228163122 ◽

2019 ◽

Vol 15 (3) ◽

pp. 273-279

Author(s):

Shweta G. Rangari ◽

Nishikant A. Raut ◽

Pradip W. Dhore

Keyword(s):

High Performance ◽

Limit Of Detection ◽

Degradation Products ◽

Analysis Data ◽

Peak Height ◽

Good Resolution ◽

Stability Indicating ◽

Limit Of Quantitation ◽

Wide Range ◽

Hptlc Method

Background:The unstable and/or toxic degradation products may form due to degradation of drug which results into loss of therapeutic activity and lead to life threatening condition. Hence, it is important to establish the stability characteristics of drug in various conditions such as in temperature, light, oxidising agent and susceptibility across a wide range of pH values.Introduction:The aim of the proposed study was to develop simple, sensitive and economic stability indicating high performance thin layer chromatography (HPTLC) method for the quantification of Amoxapine in the presence of degradation products.Methods:Amoxapine and its degraded products were separated on precoated silica gel 60F254 TLC plates by using mobile phase comprising of methanol: toluene: ammonium acetate (6:3:1, v/v/v). The densitometric evaluation was carried out at 320 nm in reflectance/absorbance mode. The degradation products obtained as per ICH guidelines under acidic, basic and oxidative conditions have different Rf values 0.12, 0.26 and 0.6 indicating good resolution from each other and pure drug with Rf: 0.47. Amoxapine was found to be stable under neutral, thermal and photo conditions.Results:The method was validated as per ICH Q2 (R1) guidelines in terms of accuracy, precision, ruggedness, robustness and linearity. A good linear relationship between concentration and response (peak area and peak height) over the range of 80 ng/spot to 720 ng/spot was observed from regression analysis data showing correlation coefficient 0.991 and 0.994 for area and height, respectively. The limit of detection (LOD) and limit of quantitation (LOQ) for area were found to be 1.176 ng/mL and 3.565 ng/mL, whereas for height, 50.063 ng/mL and 151.707 ng/mL respectively.Conclusion:The statistical analysis confirmed the accuracy, precision and selectivity of the proposed method which can be effectively used for the analysis of amoxapine in the presence of degradation products.

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Terahertz and Microwave Optical Properties of Single-Crystal Quartz and Vitreous Silica and the Behavior of the Boson Peak

Applied Sciences ◽

10.3390/app11156733 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6733

Author(s):

Mira Naftaly ◽

Andrew Gregory

Keyword(s):

Single Crystal ◽

Silica Glass ◽

Broad Band ◽

Peak Frequency ◽

Vitreous Silica ◽

Peak Height ◽

Fused Silica ◽

Boson Peak ◽

Single Crystal Quartz ◽

Crystal Quartz

Z-cut single-crystal quartz and vitreous silica (silica glass or fused silica) were evaluated for use as reference materials for terahertz and microwave measurements of complex permittivity, with Z-cut quartz confirmed as being suitable. Measurements of refractive indices and absorption coefficients for o-ray and e-ray in quartz and for vitreous silica are reported at frequencies between 0.2 and 6 THz and at 36 and 144 GHz, and compared with data reported in the literature. A previously unreported broad band was seen in the extraordinary absorption of quartz. The Boson peak in silica glass absorption was examined, and for the first time, two negative relationships have been observed: between the refractive index and the Boson peak frequency, and between the Boson peak height and its frequency.

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