Florisil column chromatography

Florisil column chromatography is effective in eliminating interfering substances in soil. The organic solvent extracts from soil samples are charged to a column plugged with Florisil which has been activated at 130 °C overnight before use. The effluents from the column with a mixed solvent such as n-hexane-acetone are concentrated to... 

Residues of flumioxazin are extracted from plant matrices with aqueous acetone. The extracted residues are partitioned into dichloromethane. The dichloromethane is removed through rotary evaporation. Partitioning between hexane-acetonitrile followed by Florisil column chromatography purifles the plant extract. Residues of flumioxazin are quantitated by gas chromatography GC. 

Residues of flumioxazin in/on soil are extracted with acetone-0.1 N HCl (5 1, v/v), partitioned into dichloromethane, cleaned up with Florisil column chromatography and quantitated by GC. 

Flumioxazin is extracted from water with dichloromethane. If needed, the sample is cleaned with Florisil column chromatography prior to quantitation by GC. 

A method for food (fish) has been reported. The sample is ground with sodium sulfate and extracted with petroleum ether. The extract is cleaned up by liquid-liquid partition, followed by Florisil column chromatography. Analysis is performed by GC/NPD. Detection limits are 0.1 ppm recovery was not reported (Lombardo and Egry 1979). 

Food (fish) Grinding with petroleum ether solvent extraction clean-up by liquid-liquid partition, Florisil column chromatography GC/NPD 0.1 ppm Not specified Lombardo and Egry 1979... 

Numerous non-fatty crops Extraction with acetonitrile and partition into petroleum ether. Concentration using K-D and purification using Florisil column chromatography. GC/KCI thermionic detector identifications by combinations of gas, thin layer, and paper chromatography No data >80 AOAC 1990... 

Three standardized methods were found in the Official Methods ofAnalysis of the Association of Official Analytical Chemists (AOAC 1990). The first of these methods is based on the extraction of crops (kale, endive, carrots, lettuce, apples, potatoes, and strawberries) with ethyl acetate and isolation of the residue followed by a sweep codistillation cleanup prior to GC/thermionic detection (Method 968.24). The second of these methods utilizes Florisil column chromatography clean-up followed by GC/FPD (Method 970.53). In the third method (Method 970.52), the sample is extracted with acetonitrile, and the residue is partitioned into petroleum ether followed by Florisil clean-up and GC/KC1 thermionic detection. Identifications are based on combinations of gas, thin-layer, and paper chromatography. The recovery for diazinon in this method is stated to be greater than 80% no data on limits of detection were given. 

Koistinen et al. [98], who studied the induction of EROD activity of 29 PCDE congeners in vitro using H4IIE rat hepatoma cells, have reported that PCDEs are inactive as inducers of EROD. A similar type of activity as that reported by Howie et al. [88] was only seen with PCDE congeners before cleanup by Florisil column chromatography. After the removal of PCDD and PCDF impurities using Florisil the activity was lost, except for PCDE 156 which was a weak inducer (TEF 1.2 x 10-5). It is possible that effects such as chloroacne reported for higher chlorinated PCDEs [12], could be due to toxic PCDF impurities. 2,3,7,8-Substituted PCDFs have been measured at ng ml-1 levels in 10 pg ml-1 PCDE solutions [98]. 

Chromatography on an alumina micro column [67] and a Florisil column [134] can be used to separate PCDEs from PCDFs. PCBs are also separated from PCDDs and PCDFs on Florisil and alumina [111, 112]. Group separation on these materials can be achieved by using sequential elution with solvents of increasing polarity. Florisil column chromatography technique has been used in mostPCDE studies [33,57,58,113,114,120,123-126,128,130,131] and alumina chromatography less [120]. Fractionation has also been performed on silica gel [51,119] and carbon [116,131,132]. 

Bulk matrix removal by liquid-solid chromatography has been performed on Florisil, silica, modified silica gel, and modified celite [51,108,115,116,121,126, 128, 132]. Silica gel (activated) [51] and the Florisil column chromatography technique [108,121,126,128] have been used to remove lipids from fish muscle, bird eggs and tissues (muscle, liver, fat), and rat tissues (muscle, liver, blood, skin) and for bulk matrix removal of sediment extracts. Extracts have been elut-... 

In addition to lipid removal, Florisil column chromatography can be used for chromatographic cleanup and to separate PCDEs from other compounds such as PCBs, PCDDs, and PCDFs. Florisil has been used activated and after deactivation with water. An activated Florisil column has been reported to separate PCDEs... 

Tomy et al. [ 14] extracted PCAs from fish and sediments by using DCM extraction, lipid removal by SX-3 Biobeads gel permeation chromatography (GPC) [53], and cleanup with Florisil column chromatography. Fractionation on Florisil was achieved by eluting with hexane (FI), which eluted all the PCBs, chlorinated benzenes, 4,4 -DDE, then with (15 85) DCM/hexane (F2), and finally with (1 1) DCM/hexane (F3). Fractions F2 and F3 contained PCAs along with 4,4 -DDT, toxaphene, cis- and frans-chlordane and other more polar organics, such as heptachlor epoxide and dieldrin. The mean percentage recovery of PCAs for this method was 85 %. 

Sample mixed with formic acid extracted with hexane cleaned up by Florisil column chromatography extract concentrated... 

Dissolve sample in a solvent/solvent mixture filter if necessary clean up by GPC Florisil column chromatography and alkali concentrate extract... 

Roelofs et al. (74, 75) obtained the crude sex pheromone by passing air over scale-infested potatoes and through a Porapak Q trap, and then extracting the absorbent with pentane. Two active compounds were isolated by Florisil column chromatography followed by HPLC on two different columns and preparative GC. 

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