scholarly journals Determination of Formaldehyde by HPLC with Stable Precolumn Derivatization in Egyptian Dairy Products

2018 ◽  
Vol 2018 ◽  
pp. 1-5 ◽  
Author(s):  
Ahmed Salem Sebaei ◽  
Ahmed M. Gomaa ◽  
A. A. El-Zwahry ◽  
E. A. Emara

Formaldehyde is one of the most dangerous chemical compounds affecting the human health; exposure to it from food may occur naturally or by intentional addition. In this study a high performance liquid chromatography method for determination of formaldehyde in dairy products was described. The dairy samples were reacted and extracted with a warmed organic solvent in the presence of derivatizing agent 2,4-dinitrophenylhydrazine (DNPH) and formaldehyde; the mixture was centrifuged and followed by diode array detection. The method is validated and gives average recovery of formaldehyde at the three different levels 0.1, 5.0, and 10.0 mg/kg varied between 89% and 96%. The method is linear from the limit of quantification 0.1 mg/kg up to 10 mg/kg levels. This method is intended for formaldehyde analyses in dairy products simply with stable derivatization, minimum residue loss, excellent recovery, and accurate results with a sensitive limit of detection 0.01 mg/kg. 90 dairy samples from milk, cheese, and yogurt were investigated from seven Egyptian governorates and all samples were free from formaldehyde.

INDIAN DRUGS ◽  
2019 ◽  
Vol 56 (09) ◽  
pp. 68-73
Author(s):  
K Vijaya Sri ◽  
M. Shiva Kumar ◽  
M. A. Madhuri ◽  
Suresha K. ◽  

In this study, a high-performance liquid chromatographic method (HPLC) was developed, validated and applied for the determination of raltegravir in biological sample like saliva. Liquid- liquid extraction was performed for isolation of the drug and elimination of saliva interferences. Samples of saliva was extracted with 50µL of ortho phosphoric acid and 3ml of methanol was added and spiked with raltegravir. The chromatographic separation was performed on Agilent Eclipse C18 (100 mm × 4.6 mm, 3.5µm) column, by using 80:20 v/v acetonitrile: water as a mobile phase under isocratic conditions at a flow rate of 1.0 mL/min for UV detection at 240 nm. Retention time of raltegravir was found to be 1.030 min. Linearity was found to be in the range of 25-1000 ng/mL with regression equation y = 13864x + 40495 and correlation coefficient 0.999. The low % RSD value indicates the method is accurate and precise. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.76 and 2.28 ng/mL, respectively. It can be concluded that this validated HPLC method is easy, precise, accurate, sensitive and selective for determination of raltegravir in saliva.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Mostafa M. H. Khalil ◽  
Ahmed M. Gomaa ◽  
Ahmed Salem Sebaei

Aflatoxin M1 is the foremost metabolite of aflatoxin B1 in humans and animals, which may be present in animal products from animals fed with aflatoxin B1 contaminated feed. In this study a high performance liquid chromatography method for determination of aflatoxin M1 in eggs was described. The egg samples were diluted with warmed water and the toxin was immunoextracted followed by fluorescence detection. The average recovery of aflatoxin M1 at the three different levels 0.05, 0.1, and 0.5 μg/kg varied between 87% and 98%. The method is linear from the limit of quantification 0.05 μg/kg up to 3 μg/kg levels. This method is intended for aflatoxin M1 analyses in eggs simply with minimum toxin lose, excellent recovery, and accurate results with the limit of detection 0.01 μg/kg.


INDIAN DRUGS ◽  
2018 ◽  
Vol 55 (10) ◽  
pp. 56-62
Author(s):  
A Anerao ◽  
◽  
V. Dighe ◽  
A Gupta ◽  
C. Patil ◽  
...  

N-Methylethanolamine is the side chain of the drug diphenhydramine hydrochloride. A sensitive high performance liquid chromatography method with pre-column derivatization was developed and validated for the determination of N-methylethanolamine impurity in diphenhydramine hydrochloride active pharmaceutical ingredient. HPLC method on column Cosmosil MS-II, C-18, 250 mm X 4.6 mm, particle size 5 μm with UV detector was used. The proposed method is specific, linear, accurate, rugged and precise. The calibration curves showed good linearity over the concentration range of 0.03 mg/g to 1.5 mg/g and the correlation coefficient was 0.999. Method had very low limit of detection (LOD) and limit of quantification (LOQ) as 0.01 mg/g and 0.03 mg/g, respectively, of the analyte. Accuracy was observed within 94.4% to 96.2%.


Author(s):  
Revathi Naga Lakshmi Ponnuri ◽  
Prahlad Pragallapati ◽  
Mastanamma Sk ◽  
Ravindra N ◽  
Venkata Basaveswara Rao Mandava ◽  
...  

ABSTRACTObjective: The objective of present work was to develop and validate a simple, fast, precise, selective, and accurate reverse phase high-performanceliquid chromatography method for the simultaneous determination of Clindamycine, Metronidazole and Clotrimazole in a pharmaceutical dosageform.Methods: The separation of these three drugs was achieved on ODS 250×4.6 mm, 5 mm C column. Mobile phase containing 0.1% ortho phosphoricacid buffer and acetonitrile in the ratio of 55:45 v/v was pumped through column at a flow rate of 1 ml/minute. Temperature was maintained at 30°Cand ultraviolet detection at 238 nm.18Results: The retention times were observed to be 2.591, 3.584, and 4.221 minutes for Clindamycine, Metronidazole, and Clotrimazole, respectively.Linearity was found to be 25-150 μg/ml Clindamycine, Metronidazole, and Clotrimazole, respectively. The method was statistically validated forlinearity, recovery, the limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision. The stress testing of the drugs individually andtheir mixture are carried out under acidic, alkaline, oxidation, photostability, and thermal degradation conditions and its degradation products arewell resolved from the analyte peaks.Conclusion: This method was successfully validated for accuracy, precision, and linearity, LOD, and LOQ.Keywords: Clindamycine, Metronidazole, Clotrimazole, Reverse phase-high performance liquid chromatography, Simultaneous determination,Degradation studies.


Author(s):  
Kamran Ashraf ◽  
Syed Adnan Ali Shah ◽  
Mohd Mujeeb

<p><strong>Objective: </strong>A simple, sensitive, precise, and accurate stability indicating HPTLC (high-performance thin-layer chromatography) method for analysis of 10-gingerol in ginger has been developed and validated as perICH guidelines.</p><p><strong>Methods: </strong>The separation was achieved on TLC (thin layer chromatography) aluminum plates pre-coated with silica gel 60F<sub>254</sub> using n-hexane: ethyl acetate 55:45 (%, v/v) as a mobile phase. Densitometric analysis was performed at 569 nm.</p><p><strong>Results: </strong>This system was found to have a compact spot of 10-gingerol at <em>R</em><sub>F</sub> value of 0.57±0.03. For the proposed procedure, linearity (<em>r</em><sup>2</sup> = 0.998±0.02), limit of detection (18ng/spot), limit of quantification (42 ng/spot), recovery (ranging from 98.35%–100.68%), were found to be satisfactory.</p><p><strong>Conclusion: </strong>Statistical analysis reveals that the content of 10-gingerol in different geographical region varied significantly. The highest and lowest concentration of 10-gingerol in ginger was found to be present in a sample of Patna, Lucknow and Surat respectively which inferred that the variety of ginger found in Patna, Lucknow are much superior to other regions of India.</p>


2013 ◽  
Vol 57 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Anna Gajda ◽  
Andrzej Posyniak ◽  
Andrzej Bober ◽  
Tomasz Błądek ◽  
Jan Żmudzki

Summary A liquid chromatography method with UV detection for determination of oxytetracycline (OTC) in honey has been developed. The samples were extracted with the solution of oxalic acid. The clean-up procedure was performed by solid phase extraction (SPE) using polymeric Strata X and carboxylic acid cartridges. Chromatographic separation was carried out on the Luna C8 analytical column with mobile phase consisting of acetonitrile-0.02 M oxalic acid. The method has been successfully validated according to the requirements of the European Decision 2002/657/EC and this method is used in routine control of oxytetracycline in honey samples. The limit of detection (LOD) and limit of quantification (LOQ) of the presented method were 10 and 12.5 μg/kg, respectively. The developed method has also been verified in quantitative determination of oxytetracycline residues in honey after experimental treatment with this product in bee colonies.


Author(s):  
Gudipally. Mounika ◽  
K. Bhavya Sri ◽  
R. Swethasri ◽  
M. Sumakanth

To develop an accurate, precise, specific high performance liquid chromatography method for quantification of Canagliflozin in bulk and dosage forms. A C18 column (250mm X 4.6mm; 5μm phenomenex) was used with mobile phase containing Acetonitrile-0.1% sodium acetate buffer (pH-4.6), (20:80) in isocratic mode. The flow rate maintained was 1.0ml/min and the U.V detector was operated at 291nm. The retention time of Canagliflozin was 3.307min and showed a good linearity in concentration range of 2-14μg/ml with correlation coefficient of 0.999. The average percent recovery was found to be 99.98%. The developed method follows validation parameters such as system suitability, linearity, precision, accuracy, limit of detection and limit of quantification and robustness as per ICH guidelinesQ2(R1). The proposed method was found to provide faster retention time with sharp resolution with linearity at a lowest concentration as compared to previous methods and this method is validated as per International conference on harmonization guidelines and successfully applied for bulk and pharmaceutical dosage form.


2012 ◽  
Vol 56 (3) ◽  
pp. 329-333 ◽  
Author(s):  
Ewelina Patyra ◽  
Ewelina Kowalczyk ◽  
Krzysztof Kwiatek

Abstract High performance liquid chromatography method with diode array detection (HPLC-DAD) was developed and optimised for the determination of tetracyclines (TCs) in medicated feedingstuffs. The extraction of the analyte from feedingstuffs was performed with Na2EDTA-McIlvaine buffer (pH 2.5 and pH 4). The extracts were cleaned up by solid phase extraction using octadecyl cartridges (C18). The samples were dried up and redissolved in the mixture of oxalic acid and methanol. Separation was performed on reserved phase column (Phenomenex C18, 250 x 4.6 mm, 5 μm) by multistep gradient elution, which provided better chromatographic separation. The analysis was performed at a wavelength of 390 nm. Validation study of the method revealed that all obtained calibration curves showed good linearity R= 0.9985 for doxycycline (DC) and R= 0.9981 for chlorotetracycline (CTC) over the range of 25-2,000 mg/kg. The analytical procedure was successfully adapted for quantitative determination of DC and CTC in medicated feedingstuff samples. Validation included determination of specificity, linearity, and repeatability. Mean recovery for spiked samples was 93.1% for CTC and 93.2% for DC. The results of validation of the analytical procedure proved that presented method is efficient, precise and useful for quantification of DC and CTC in medicated feedingstuffs.


2020 ◽  
Vol 8 (2) ◽  
pp. 1-7
Author(s):  
Ihsan M. Shaheed ◽  
Saadiyah A. Dhahir

The quinolizindine alkaloid compound, oxymatrine pesticide, was analysis in the river water samples collected from different agriculture areas in the Iraqi city of Kerbala and also in its formulation using developed reverse-phase high-performance liquid chromatography method. Acetonitrile:methanol (60:40 v/v) was chosen as mobile phase at pH (7.0), flow rate 0.5 mL/min, and 20 µL as volume injection. Modified ecological-friendly method, dispersive liquid-liquid microextraction, was used for the extraction of oxymatrine from water samples. Linearity study was constructed from 0.1 to 70 μg/mL at λmax 205 nm. The limit of detection and limit of quantification were 0.025 and 0.082 μg/mL, respectively, and the relative standard deviation (RSD) % was 0.518%. Three spiked levels of concentration (20.0, 40.0, and 70.0 μg/mL) were used for the validation method. The percentage recovery for the three spiked samples was ranged between 98.743 and 99.432 and the RSD% was between 0.051 and 0.202%, the formulation studies of oxymatrine between 99.487 and 99.798, and the RSD% was ranged from 0.045 to 0.057%. The developed method can be used accurately and selectively for the determination of oxymatrine in environmental samples and in the formulation.


2020 ◽  
Vol 17 (34) ◽  
pp. 1046-1054
Author(s):  
Ihsan Mahdi SHAHEED ◽  
Saadiyah Ahmed DHAHIR

The triazole, tebuconazole pesticide, was determined in its formulation and also in the river water samples collected from different agriculture areas in the Iraqui city of Kerbala using developed high-performance liquid chromatography method(HPLC) with UV-visible detection, The mobile composition phase was a mixture of acetonitrile:methanol (50:50 v/v) and the column was C18 (250 cm x 4.6 mm,5μm). Also modified dispersive liquidliquid microextraction (DLLME), which is regarded as an ecological -friendly method, was used for the extraction of tebuconazole from water samples using acetonitrile and chloroform as solvents extraction and dispersive agent, respectively. Linearity to maintain the calibration curve was achieved from (0.1-70) μg.mL-1 with a limit of detection(0.053) μg.mL-1 and limit of quantification (0.174) μg.mL-1. Three spiked levels of concentration (1.0, 5.0, and 10) μg.mL-1 were used for the validation of the method. The relative standard deviation (RSD%) was (0.294- 0.813)%, and the percentage recovery was (100.001-100.005). The formulation studies for two different concentrations (10 and 40) μg.mL-1, which prepared from tebuconazole formulation (Raxil ODS2 2%), gave acceptable percentage recovery between (98.956-99.833). The developed method can be used accurately for the determination of tebuconazole in water samples and in the formulation of tebuconazole effectively.


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