Extraction of Lipids from Raw Beef Lean by Using Various Solvent Systems

1967 ◽  
Vol 50 (2) ◽  
pp. 250-255 ◽  
Author(s):  
Susie N Hagan ◽  
Elizabeth W Murphy ◽  
Lydia M Shelley
Keyword(s):  
Sample Preparation ◽  
Drying Method ◽  
Preparation Methods ◽  
Drying Procedures ◽  
Aoac Method ◽  
Solvent Systems ◽  
Total Fat ◽  
Layer Chromatography ◽  
Chloroform Methanol

Abstract Study shows that chloroform-methanol extraction to remove lipids from beef yielded percentages of total fat equal to or greater than those obtained by the AOAC method. The ratio of phospholipid to triglyceride was always higher in the chloroform-methanol extracted samples. Six extraction methodsolvent system combinations, three drying procedures, and two sample preparation methods were compared. Tlie extracted lipids were separated by thin layer chromatography. The ratio of phospholipid to triglyceride was calculated after the spectrophotometric determination of the ester groups present. Acid-hydrolysis-Rohrig gave the lowest yield of total lipid and of phospholipid. Sample preparation method or drying method caused few significant dif. ferenccs in the proportions of total solids and of total lipids in the beef cuts analyzed

Two Validated Chromatographic Methods for Determination of Ciprofloxacin HCl, One of its Specified Impurities and Fluocinolone Acetonide in Newly Approved Otic Solution

2021 ◽  
Author(s):  
Mahmoud A Tantawy ◽  
Israa A Wahba ◽  
Samah S Saad ◽  
Nesrin K Ramadan
Keyword(s):  
High Performance ◽  
Fluocinolone Acetonide ◽  
Ultraviolet Detection ◽  
Chromatographic Methods ◽  
Bulk Powder ◽  
Developing System ◽  
Layer Chromatography ◽  
Chloroform Methanol ◽  
Linear Regressions

Abstract Two sensitive, selective and precise chromatographic methods have been established for concomitant quantification of ciprofloxacin HCl (CIP), fluocinolone acetonide (FLU) along with ciprofloxacin impurity A (CIP-imp A). The first method was thin-layer chromatography (TLC-densitometry) where separation was accomplished using TLC silica plates 60 G.F254 as a stationary phase and chloroform–methanol–33%ammonia (4.6:4.4:1, by volume) as a developing system. The obtained plates were scanned at 260 nm over concentration ranges of 1.0–40.0, 0.6–20.0 and 1.0–40.0 μg band−1 for CIP, FLU and CIP-imp A, respectively. The second method was based on high-performance liquid chromatography using a Zorbax ODS column (5 μm, 150 × 4.6 mm i.d.) where adequate separation was achieved through a mobile phase composed of phosphate buffer pH 3.6–acetonitrile (45:55, v/v) at flow rate 1.0 mL min−1 with ultraviolet detection at 254 nm. Linear regressions were obtained in the range of 1.0–40.0 μg mL−1 for CIP, 0.6–20.0 μg mL−1 for FLU and 1.0–40.0 μg mL−1 for CIP-imp A. The suggested methods were validated in compliance with the International Conference on Harmonization guidelines and were successfully applied for determination of CIP and FLU in bulk powder and newly marketed otic solution.

scholarly journals Overview of the analytical methods for vancomycin and/or teicoplanin determination in biological matrices

2017 ◽  
Vol 71 (2) ◽  
pp. 87-97 ◽  
Author(s):  
Ana Stajic ◽  
Biljana Jancic-Stojanovic
Keyword(s):  
Sample Preparation ◽  
Bacterial Infections ◽  
Multidrug Resistant ◽  
Glycopeptide Antibiotics ◽  
Biological Matrices ◽  
Preparation Methods ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Improved Methods

Background. Teicoplanin and vancomycin are glycopeptide antibiotics currently in use for treatment of multidrug-resistant bacterial infections. Scope and Approach. Severe undesirable effects, such as ototoxicity, nephrotoxicity and neutropenia have been reported for vancomycin and teicoplanin, which necessitates monitoring the concentration of these two drugs in different biological samples. In order to obtain precise and accurate results, sensitive, reliable and fast methods are necessary. The main aim of this mini review is to give a clear and concise overview of the recently developed, validated, novel and improved methods for glycopeptide antibiotic analyses in various biological matrices. Also, the variability of the matrices requires optimal and effective sample preparation procedures to be developed, and so these are discussed. Key Findings and Conclusions. Different liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods have been described for quantitative determination of glycopeptide antibiotics in various biological matrices. It was shown that protein precipitation was a convenient method for sample preparation despite the high number of novel sample preparation methods.

Sample Preparation Optimization for EDXRF Analysis of Portland Cement

1988 ◽  
Vol 32 ◽  
pp. 221-226
Author(s):  
Wayne Watson ◽  
Jim Parker ◽  
Anthony R. Harding
Keyword(s):  
Sample Preparation ◽  
Portland Cement ◽  
Preparation Methods ◽  
X Ray ◽  
Accuracy And Precision ◽  
Edxrf Analysis ◽  
Analytical Accuracy ◽  
Minimum Detection Limits ◽  
Sample Preparation Methods

AbstractVarious sample preparation methods for Energy Dispersive X-ray Fluorescence (EDXRF) analysis of Portland cement were compared in order to evaluate improvement in analytical accuracy and precision. Sample preparation requirements for EDXRF are slightly different than for Wavelength Dispersive X-ray Fluorescence (WDXRF), and the methods commonly used in WDXRF are not optimized for EDXRF. Primarily, the work focuses on techniques for producing a fused sample with the lowest practical concentration of lithium borate flux. Determination of minimum detection limits were made from samples with varying proportions of flux in order to evaluate analytical optimization. Ease and reproducibility of preparation of the sample was also considered.

Comparison of Sample Preparation Methods for Phosphorus in Grains and Stock Feeds

1968 ◽  
Vol 51 (4) ◽  
pp. 771-773
Author(s):  
Aaron E Rash
Keyword(s):  
Sample Preparation ◽  
Perchloric Acid ◽  
Sodium Molybdate ◽  
The Other ◽  
Acid Digestion ◽  
Preparation Methods ◽  
Commercial Feeds ◽  
Sample Preparation Methods ◽  
Good Agreement

Abstract The nitric-perchloric acid digestion, 22.070(b) and 22.073, for the determination of phosphorus in grains and stock feeds was compared with three other methods of sample preparation (destruction of organic material) : quinoline molybdate precipitation, perchloric-sulfuric-sodium molybdate digestion, and the plant method. The values obtained by the nitric-perchloric acid method were not in good agreement with those obtained by the other methods studied. Six samples of commercial feeds and one barley sample were analyzed. The barley sample gave very poor recoveries by method 22.073.

Comparison of QuEChERS with Traditional Sample Preparation Methods in the Determination of Multiclass Pesticides in Soil

2019 ◽  
Vol 102 (1) ◽  
pp. 46-51 ◽  
Author(s):  
Rada D Ðurović-Pejčev ◽  
Vojislava P Bursić ◽  
Tijana M Zeremski
Keyword(s):  
Sample Preparation ◽  
Organophosphorus Pesticides ◽  
Soxhlet Extraction ◽  
Soil Samples ◽  
Gas Chromatography Mass Spectrometry ◽  
Quechers Method ◽  
Preparation Methods ◽  
Soxhlet Method ◽  
Solid Liquid

Abstract Background: The increased use of pesticides leads to permanent pollution of soil, and there is a need for continuous monitoring of these agrochemicals in soil. Objective: Three methods for the simultaneous determination of 12 pesticides belonging to eight chemical groups in soil samples were tested and compared based on analytical parameters. Methods: The quick, easy, cheap, effective, rugged, and safe (QuEChERS); traditional solid–liquid extraction (SLE); and Soxhlet extraction were used for soil sample preparation, while detection and quantification of pesticides were performed using gas chromatography–mass spectrometry (GC-MS). Results: The tested methods featured good sensitivity, and with the exception for carbofuran (Soxhlet method, LOD = 29 μg/kg), for the rest of the pesticides, the studied LODs were less than 12 μg/kg. Except for simazine and carbofuran, LODs obtained by Soxhlet extraction were lower than values obtained by other two methods, whereas QuEChERS gave lower LODs than the traditional SLE method for all compounds except atrazine and acetochlor. The recoveries obtained applying QuEChERS, traditional SLE, and Soxhlet methods for multiple analyses of soil samples fortified at 10, 75, and 200 μg/kg of each pesticide were in the ranges 54–103, 40–91, and 12–92%, respectively. Except for chlorothalonil, the highest recoveries were obtained by the QuEChERS method. Soxhlet was better than traditional SLE method for chlorothalonil, heptachlor, and aldrin; organophosphorus pesticides (fenitrothion and diazinon) and trifluralin, gave similar recoveries for both methods. All three methods were proven to be repeatable, with RSDs lower than 19%. Conclusions: Although all tested methods showed as satisfactory regarding most analytical parameters, QuEChERS method showed much better results in terms of confidence, indicating that traditional SLE and Soxhlet extraction still need improvements for determination of multiclass pesticides in soil samples.

Method for the Detection and Estimation of Ochratoxin A in Some Cereal Products

1967 ◽  
Vol 50 (2) ◽  
pp. 366-370
Author(s):  
P M Scott ◽  
T B Hand
Keyword(s):  
Ochratoxin A ◽  
Aqueous Methanol ◽  
Whole Wheat Flour ◽  
Cereal Products ◽  
Whole Wheat ◽  
Sample Extract ◽  
Final Sample ◽  
Aoac Method ◽  
Layer Chromatography

Abstract A method for the detection and semiquantitative estimation of ochratoxin A in flour and other cereal products is described which can be used in conjunction with analysis of the foodstuff for aflatoxins. The sample is extracted with aqueous methanol and n-hexane and the toxin is partitioned on a Celite column, as in the AOAC method for determination of aflatoxins in peanut products. Ochratoxin A is separated by thin layer chromatography and estimated by the intensity of fluorescence compared with that of a reference standard. By this procedure, 0.01 μg ochratoxin A can be detected in 10 μl final sample extract, corresponding to a detection limit of about 25 μg/kg cereal foodstuff. The method is applicable to whole wheat flour, corn meal, barley cereal, and rice cereal. Recoveries of 80—100% of added ochratoxin A were obtained

Simultaneous Extraction and Fractionation and Thin Layer Chromatographic Determination of 14 Mycotoxins in Grains

1979 ◽  
Vol 62 (3) ◽  
pp. 573-578 ◽  
Author(s):  
Yuiko Takeda ◽  
Etsuko Isohata ◽  
Ryuji Amano ◽  
Mitsuru Uchiyama
Keyword(s):  
Thin Layer ◽  
Chromatographic Determination ◽  
Chloroform Extract ◽  
Simultaneous Extraction ◽  
Polished Rice ◽  
Rough Rice ◽  
The Individual ◽  
Layer Chromatography ◽  
Chloroform Methanol

Abstract A simple, systematic analytical method for multiple mycotoxins was developed for detecting 14 mycotoxins: aflatoxins Bl, B2, G1, and G2, sterigmatocystin, T-2 toxin, diacetoxyscirpenol, neosolaniol, fusarenon X, zearalenone, ochratoxin A, citrinin, luteoskyrin, and rugulosin. These mycotoxins were extracted with 20% H2SO4-4% KCl-acetonitrile (2+20+178), defatted with isooctane, and transferred to chloroform. The chloroform extract was cleaned up by silica gel column chromatography; the first 10 toxins were eluted with chloroform-methanol (97+3) and the remaining 4 toxins with benzene-acetone-acetic acid (75+20+5). Each fraction was analyzed by thin layer chromatography for the final determination. The method has been applied to polished rice, rough rice, corn, wheat, and peanuts as an analytical screening procedure. The detection limits in these commodities ranged from 10.0 to 800.0 μg/kg, depending on the mycotoxin, but all limits were superior to those obtained for the individual mycotoxins by using other methods.

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