Fully automated and simplified radiosynthesis of [18F]-3′-deoxy-3′-fluorothymidine using anhydro precursor and single neutral alumina column purification

2009 ◽  
Vol 283 (3) ◽  
pp. 741-748 ◽  
Author(s):  
S. K. Nandy ◽  
M. G. R. Rajan
Keyword(s):  
Alumina Column ◽  
Neutral Alumina

Gas Chromatographic/Mass Spectrometric Confirmation of Leucomalachite Green in Catfish (Ictalurus punctatus) Tissue

1995 ◽  
Vol 78 (4) ◽  
pp. 971-977 ◽  
Author(s):  
Sherri B Turnipseed ◽  
José E Roybal ◽  
Jeffrey A Hurlbut ◽  
Austin R Long
Keyword(s):  
Solid Phase Extraction ◽  
Ictalurus Punctatus ◽  
Solid Phase ◽  
Mass Spectrometric ◽  
Phase Extraction ◽  
Neutral Alumina ◽  
Ms Analysis ◽  
Solid Phase Extraction Cartridge ◽  
Leucomalachite Green ◽  
Chromatographic Mass

Abstract A gas chromatographic/mass spectrometric (GC/MS) method was developed to confirm the presence of leucomalachite green (LMG), a metabolite of the triphenylmethane dye malachite green (MG), in catfish tissue. Residues were isolated according to a previously described liquid chromatographic (LC)A/IS spectrometric analysis of MG and LMG in fish. In our isolation procedure, analytes are extracted from tissue with acetonitrile–buffer, partitioned into CH2CI2, and applied to neutral alumina and propylsulfonic acid solid-phase extraction cartridges. Before GC/MS analysis, extracts prepared for the LC determinative method are eluted from a cyano solid-phase extraction cartridge, extracted into organic solvent, and concentrated for GC/MS analysis. Selected ion monitoring was performed by using 5 diagnostic ions (m/z 330,329,253,210, and 165) of LMG. The method was validated by confirming LMG in tissue fortified with mixtures of MG and LMG (5 and 10 ng/g each) and in tissue from fish that had been exposed to low levels of MG.

Liquid Chromatographic Determination of Sulfamoyldapsone in Swine Tissues

1987 ◽  
Vol 70 (6) ◽  
pp. 1031-1032
Author(s):  
Yuuko S Endoh ◽  
Ryozo Yamaoka ◽  
Nobuo Sasaki
Keyword(s):  
Detection Limit ◽  
Quantitative Determination ◽  
Chromatographic Determination ◽  
Alumina Column ◽  
Average Recovery ◽  
Diaminodiphenyl Sulfone ◽  
Alumina Column Chromatography ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A liquid chromatographic (LC) method is described for the quantitative determination of sulfamoyldapsone (2-sulfamoyl-4,4'-diaminodiphenyl sulfone) in swine muscle, liver, kidney, and fat. Sulfamoyldapsone was extracted from tissues with acetonitrile saturated with n-hexane. The extract was washed with n-hexane saturated with acetonitrile, concentrated, and cleaned up by alumina column chromatography. Sulfamoyldapsone was separated on an ODS column by using acetonitrile-methanol-water (6 + 18 + 76) and was detected at 292 nm. Overall average recovery of sulfamoyldapsone added to tissues at levels of 0.1 and 0.5 /μg/g was 93.3% ± 6.0. Detection limit was 0.02 μg/g in these tissues.

FURTHER INVESTIGATIONS INTO THE CHEMICAL BASIS OF INSECT–HOST PLANT RELATIONSHIPS IN AN OLIGOPHAGOUS INSECT, PLUTELLA MACULIPENNIS (CURTIS) (LEPIDOPTERA: PLUTELLIDAE)

1963 ◽  
Vol 41 (6) ◽  
pp. 923-929 ◽  
Author(s):  
J. K. Nayar ◽  
A. J. Thorsteinson
Keyword(s):  
Activated Carbon ◽  
Mustard Oil ◽  
Plant Tissues ◽  
Cellulose Powder ◽  
Insect Host ◽  
Feeding Stimulants ◽  
Neutral Alumina ◽  
Powder Activated Carbon ◽  
Layer Chromatography ◽  
Relative Palatability

Samples of nine crystalline mustard oil glucosides including sinigrin were isolated from plant tissues of species in the families Cruciferae and Tropaeolaceae. The isolations were achieved by the use of column chromatography on neutral alumina, cellulose powder, activated carbon; by paper and thin-layer chromatography; and by crystallization from methanol–water mixtures.Feeding responses of fifth instar larvae of Plutella maculipennis (Curtis) were tested on agar–cellulose diets containing individual glucosides at various concentrations in the presence or absence of 0.1 M glucose. The amount of feeding was measured by counts of frass pellets produced by the larvae during the test period. All the above-mentioned glucosides were found to act as feeding stimulants for the larvae of P. maculipennis. However, the relative palatability of these glucosides at the same concentration (20 mg per 10 ml of water in the diet) was found to be in the following order: progoitrin > glucocheirolin = glucoconringiin = glucoerucin > glucotropaeolin = sinigrin = sinalbin > gluconasturtiin = gluconapin. Higher concentrations of the glucosides, gluconasturtiin, and gluconapin were toxic to the larvae.

Rapid GLC Method for Determining Residues of Fenthion, Disulfoton, and Phorate in Corn, Milk, Grass, and Feces

1969 ◽  
Vol 52 (6) ◽  
pp. 1231-1237
Author(s):  
M C Bowman ◽  
Morton Beroza
Keyword(s):  
Alumina Column ◽  
Flame Photometric Detector ◽  
Detector Sensitivity ◽  
Oxygen Analog ◽  
Photometric Detector

Abstract Residues of fenthion, disulfoton, and phorate may each consist of the parent insecticide and five metabolites formed by oxidation of the thionophosphate and sulfide groups in each molecule. The analysis of these residues has been simplified and speeded by oxidizing the insecticide and its metabolites to the oxygen analog sulfone with m-chloroperbenzoic acid. After removal of the acid on an alumina column, the compound is determined by GLC with a flame photometric detector. Sensitivity (twice noise) is at least 0.001 ppm. When equal amounts of the six compounds were added to corn, milk, grass, and feces at levels of 0.2 to 5.0 ppm, the recoveries were 95–96% for fenthion and 74–82% for disulfoton and phorate. In analyses of field-treated samples, recoveries were 89–92% of those obtained by previous procedures, which are much more time-consuming.

Quantitative Determination of Thiourea in Citrus Fruits

1977 ◽  
Vol 60 (3) ◽  
pp. 699-701
Author(s):  
Bernadette Mandrou ◽  
Suzanne Brun ◽  
Amara Kingkate
Keyword(s):  
Colorimetric Assay ◽  
Colorimetric Method ◽  
Extraction Technique ◽  
Citrus Fruits ◽  
Alumina Column ◽  
Orange Peels ◽  
Ultraviolet Reflectance ◽  
Spectrometric Measurements ◽  
Colorimetric Reaction

Abstract A quantitative method for thiourea determination in orange peels is proposed, with direct reflectance spectrometric measurements on chromatoplates. Thiourea is separated on a silica gel plate with methanol-chloroform (10+90), and the spots are characterized with 2,6-dichloroquinone chloroimide; this colorimetric reaction is unstable, so thiourea is quantitated on the chromatogram by direct ultraviolet reflectance spectrometric measurements at 240 nm. Comparison between this method and the AOAC colorimetric method shows interferences and higher results in the colorimetric assay. By slightly modifying the extraction technique, such as purifying the extract on an alumina column, it is possible to decrease these interferences and to avoid erroneous results with the AOAC colorimetric method. For both methods, colorimetry in solution and reflectometry on chromatoplates, applied after the proposed extraction technique, the sensitivity is about 1 ppm and the reliabilities are similar.

Development of a Method for the Determination of Pyrimethamine Concentrations in Feeds by Ion-Pairing High-Performance Liquid Chromatography

2002 ◽  
Vol 65 (4) ◽  
pp. 688-691 ◽  
Author(s):  
P. S. GONG ◽  
S. L. JENG ◽  
Y. F. HSU ◽  
C. C. LIN ◽  
S. Y. LIN
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Ion Pairing ◽  
Reversed Phase ◽  
Hplc Method ◽  
Alumina Column ◽  
Tetramethylammonium Chloride ◽  
Array Detection

An ion-pairing reversed-phase high-performance liquid chromatography (HPLC) method with diode array detection at 280 nm was developed to determine pyrimethamine concentrations in feed for laying hens. Pyrimethamine was extracted with a mixture of 5% isobutanol and 95% benzene, and the extract was cleaned up on an alumina column. The drug was eluted from an Intersil ODS-3V column (250 by 4.6 mm) with a mixture of 25% acetonitrile and 75% water (vol/vol) containing 0.01 M tetramethylammonium chloride as an ion-pairing agent and adjusted with acetic acid to pH 3.5. The flow rate was 1.0 ml/min. Mean recovery of pyrimethamine from supplemented feeds at concentrations of 2, 4, and 5 μg/g of feed were 100.5, 103.5, and 100.8%, respectively. Precision within a day ranged from 4.3 to 7.0% for the three concentrations, and day-to-day precision was 5.3% for feed supplemented at a concentration of 4 μg/g. No chromatographic interference was detected from other 2,4-diaminopyrimidine compounds or other major drugs used in poultry.

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