scholarly journals A Rapid, Sensitive Thin Layer Chromatography Procedure for the Detection of Fumonisin B1 and B2

1992 ◽  
Vol 4 (3) ◽  
pp. 326-329 ◽  
Author(s):  
George E. Rottinghaus ◽  
Charles E. Coatney ◽  
Harry C. Minor
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Fumonisin B1 ◽  
Sodium Borate ◽  
Reverse Phase ◽  
University Of Missouri ◽  
Tlc Plates ◽  
Green Fluorescent ◽  
Sodium Borate Buffer ◽  
Layer Chromatography

A thin layer chromatography (TLC) method was developed for the detection of fumonisin B1 and B2 in corn and corn-based feedstuffs. Finely ground samples were extracted with acetonitrile: water (1: 1), filtered, and applied to C18 cleanup columns. The columns were washed with 1% aqueous KCl followed by acetonitrile: 1% aqueous KC1 (1:9), and the fumonisins were eluted with acetonitrile: water (7:3). The eluants were concentrated and spotted on reverse-phase C18 TLC plates along with fumonisin B1 and B2 standards, and the plates were developed in methanol: 4% aqueous KCl (3:2). The fumonisins were visualized by spraying the TLC plates successively with 0.1 M sodium borate buffer, fluorescamine, and 0.01 M boric acid. The plates were then dried and examined under longwave ultraviolet light. Fumonisin B1 and B2 appeared as bright yellowish-green fluorescent bands at Rfs of 0.5 and 0.1, respectively. The detection limit for the fumonisins on the TLC plate was 0.1 ppm in corn. Recoveries from spiked samples averaged >80%. The identification of the fumonisins was confirmed by hydrolyzing the parent compounds of B1 and B2 to their respective C22 amino-alcohols and reexamining by TLC with the same visualizing reagents. This procedure was used to survey 193 corn samples collected from University of Missouri test plots in 1990 for fumonisin B,. Fumonisin B1 was detected in 15% of the corn samples.

scholarly journals identification of phylloquinone in cattle samples using T.L.C. method

2010 ◽  
pp. 75-78
Author(s):  
Lucian Bara
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Mass Spectroscopy ◽  
Vitamin K ◽  
Direct Method ◽  
Unknown Origin ◽  
Reverse Phase ◽  
Tlc Plates ◽  
Layer Chromatography

A case of hemorrhage of unknown origin was observed in cattle and liver samples were submitted for assay of Vitamin K orpossible cuomarol. After evaluating normal and reverse phase Thin Layer Chromatography (TLC) plates and different solvents,reverse phase TLC plate with indicator and methylene chloride:methanol 70:30 were chosen for direct method of detection andindication of Vitamin K.Gass Chromatography and Densitometry were used to quantitate the Vitamin K present in liver samples andconfirmation of Vitamin K was done by Mass Spectroscopy.

Analysis of Dairy Products for Chlorinated Insecticide Residues by Thin Layer Chromatography

1966 ◽  
Vol 49 (4) ◽  
pp. 795-800
Author(s):  
William A Moats
Keyword(s):  
Aluminum Oxide ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Silica Gel ◽  
Color Development ◽  
Tlc Plates ◽  
One Step ◽  
Rf Values ◽  
Tlc Analysis ◽  
Layer Chromatography

Abstract Butterfat and milk samples were analyzed for chlorinated insecticides by thin layer chromatography (TLC) on aluminum oxide or silica gel plates containing a small amount of silver nitrate. The adsorbent was washed with distilled water before preparing the plates. A one-step cleanup on a partially inactivated Florisil column was performed prior to TLC analysis. For color development, the TLC plates were sprayed lightly with hydrogen peroxide to suppress possible interference from fat and then steamed before exposure to ultraviolet light to accelerate and intensify the color reaction. Rf values for a number of solvent systems on aluminum oxide and silica gel plates are given. With this procedure, 0.05 μg or less of insecticide can be detected in a 0.4 g butterfat sample or the extract from 10 ml milk.

Simplified Method for Microscale Production and Quantification of Aflatoxin in Broth1

1984 ◽  
Vol 47 (7) ◽  
pp. 526-529 ◽  
Author(s):  
WEI-YUN J. TSAI ◽  
JIMMY D. LAMBERT ◽  
LLOYD B. BULLERMAN
Keyword(s):  
Solvent Extraction ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Frozen Storage ◽  
Aflatoxin Production ◽  
Production Studies ◽  
Simplified Method ◽  
Tlc Plates ◽  
Layer Chromatography ◽  
Yeast Extract Sucrose

A simplified method for aflatoxin production studies is described. The mold was cultured in 4-dram (15 ml) vials containing 5 ml of yeast extract sucrose broth, and aflatoxin levels were determined by direct spotting of the broth on thin layer chromatography (TLC) plates and quantitating by spectrodensitometry. Equivalent levels of aflatoxins were produced in vials as compared to flasks. When compared to conventional TLC after solvent extraction, direct spotting was rapid, economical and statistically equivalent. Heating broth cultures (121°C, 15 s) before TLC improved the release of aflatoxin from mycelial mats. Aflatoxins were unstable in YES broth during 3 months of frozen storage.

Detection of Ochratoxin A in Barley, Using Silica Gel Minicolumns

1975 ◽  
Vol 58 (1) ◽  
pp. 156-158
Author(s):  
Benedicte Hald ◽  
Palle Krogh
Keyword(s):  
Sodium Bicarbonate ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Ochratoxin A ◽  
Silica Gel ◽  
Fluorescent Band ◽  
Contamination Levels ◽  
Simplified Procedure ◽  
Green Fluorescent ◽  
Layer Chromatography

Abstract A simplified procedure has been developed to detect ochratoxin A in cereals which can be used in the field where equipment for thin layer chromatography is not available. The procedure includes extraction of the acidified sample with chloroform, purification over sodium bicarbonate, and minicolumn chromatography. Under longwave ultraviolet light ochratoxin A appears as a blue-green fluorescent band at the lower end of the column. Contamination levels as low as 12 ppb can be detected by this method.

scholarly journals Determination of New Antidepressants in Pharmaceuticals by Thin-Layer Chromatography with Densitometry

2010 ◽  
Vol 93 (3) ◽  
pp. 778-782 ◽  
Author(s):  
Tatána Gondová ◽  
Iveta Petríková
Keyword(s):  
Thin Layer ◽  
Stationary Phase ◽  
Thin Layer Chromatography ◽  
Mobile Phase ◽  
Pharmaceutical Formulations ◽  
Simultaneous Separation ◽  
Tlc Plates ◽  
Precision And Accuracy ◽  
Layer Chromatography

Abstract A new and simple TLC-densitometry method has been developed for the simultaneous separation of the two noradrenergic and specific serotonergic antidepressants mirtazapine and mianserine and validated for their determination in commercially available tablets. The method used TLC plates precoated with silica gel 60F254 as the stationary phase, and the mobile phase consisted of hexaneisopropanol25 ammonia (70 + 25 + 5, v/v/v). Densitometric analysis was carried out in the absorbance mode at 280 nm. The method was validated in accordance with International Conference on Harmonization guidelines in terms of linearity, LOD, LOQ, precision, and accuracy. Calibration curves were linear (R2 > 0.9970) with respect to peak area in the concentration range of 5002500 and 5005000 ng/spot for mirtazapine and mianserine, respectively. The LODs were 20 and 35 ng/spot for mirtazapine and mianserine, respectively. The described method was successfully applied to the determination of mirtazapine and mianserine in their pharmaceutical formulations with recovery ranging from 99.83 to 101.20 of the labeled amount of the compounds. The proposed method can be used in routine QC of these drugs in pharmaceutical formulations.

Computerized System to Quantify Aflatoxin Using Thin Layer Chromatography1

1990 ◽  
Vol 17 (2) ◽  
pp. 96-100 ◽  
Author(s):  
T. B. Whitaker ◽  
J. W. Dickens ◽  
A. B. Slate
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Measurement Errors ◽  
Regression Equation ◽  
Fluorescent Intensity ◽  
Percent Error ◽  
Sample Extract ◽  
Tlc Plates ◽  
Layer Chromatography ◽  
Computerized System

Abstract A microcomputer was interfaced to an instrument (spotmeter) previously designed to measure the fluorescent intensity of aflatoxin spots on thin layer chromatography (TLC) plates. Software was developed that uses a cubic regression equation to describe the relationships between the spotmeter readings and the known quantities of aflatoxin in standard spots on TLC plates. The regression technique also provides methods to detect spotting and/or measurement errors. Based on the regression equation and measurements of sample extract spots on the same TLC plate, the system computes and records the amount of aflatoxin in the sample extract spots and the concentration of aflatoxin that was in the extracted sample. The percent error associated with computed amounts of aflatoxin in sample extract spots is affected by the amount of aflatoxin in the sample extract spots and standard spots on the plate. The average percent error ranged from 14.9% for a 2.6 ng spot of 4.1% for a 13 ng spot.

Separation of Barbiturates Using Reverse-Phase Thin-Layer Chromatography

1980 ◽  
Vol 16 (2) ◽  
pp. 219-221 ◽  
Author(s):  
William Bress ◽  
Kenneth Ziminski ◽  
Walter Long ◽  
Thomas Manning ◽  
Leslie Lukash
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Reverse Phase ◽  
Layer Chromatography
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