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Columns, cleaning

Total surface area MW lOOA /molecule 6 x 10 molecules/ mol 9 mg 300m lOOg/mol [Pg.127]

Therefore about 20% of the stationary phase surface could potentially be covered with these impurities. [Pg.127]


Sharman, M. and Gilbert, J., Automated aflatoxin analysis of foods and animal feeds using immunoaffinity column clean-up and high-performance liquid chromatographic determination, /. Chromatogr., 543, 220, 1991. [Pg.195]

Human adipose tissue Homogenization solvent extraction GPC and Florisil column clean-up Capillary GC/NPD confirmation by GC/MS Low ng/g 69-104% LeBel and Williams 1983... [Pg.323]

It is absolutely crucial that you preclean your sample. Any decomposed or insoluble material will stick to the top of the column and can continually poison further runs. There are a few ways to keep your column clean. [Pg.247]

The sample extract from the soil sample is dissolved in 20ml of chloroform, using an ultrasonic cleaner to facilitate solution. This and a 10ml chloroform rinse are added to a dry lOg Florisil chromatographic column and eluted with an additional 110ml of chloroform. All the eluate is collected in a Kuderna-Danish unit and evaporated just to dryness, then the first 5g Florisil column clean-up procedure is followed. [Pg.288]

Tsuda et al. [16] determined NP and OP in bioaccumulation experiments with freshwater fish. The analytes were extracted with acetonitrile and the lipid in the sample extract was eliminated by partitioning between hexane and acetonitrile. After Florisil PR column clean-up, the sample extract was analysed by GC-MS in the SIM mode. [Pg.460]

Sulfuric acid optional sillica gel blood) column clean-up if PCBs are present... [Pg.203]

Ai r Collection on particulate filter and polyurethane foam Soxhlet extraction alumina column clean-up GC/ECD 0.1 ng/m3 >95... [Pg.211]

Indoor air Collection on filter and PUF plug solvent extract optional alumina column clean-up (ASTM D 4861) GC/ECD or GC/ECD confirmation on second GC column. 01 ng/m3a 90-110... [Pg.211]

Waste water Solvent extraction column clean-up (EPA Method 617) GC/ECD confirmation by GC/MS 0.15 ng/L 89.1 EPA 1992b... [Pg.212]

Milk Solvent extaction Florisil column clean-up... [Pg.215]

Milk Oxalate/solvent extraction GPC separation optional clean-up on alumina Florisil column clean-up, if needed... [Pg.215]

Lipid extraction with acetone-hexane fractionation from fat by gel permeation chromatography Florisil column clean-up. [Pg.99]

Methods are available for monitoring 1,4-dichlorobenzene in urine and tissues, particularly adipose tissue and mother s milk. Solvent extraction, silica gel column clean-up, and GC/ECD or GC/PID analysis has been used for urine (Langhorst and Nestrick 1979), mother s milk (Jan 1983), and adipose tissue (Jan 1983). Recovery is good (>80% recovery) and detection limits are in the low-ppb range (Jan 1983 Langhorst and Nestrick 1979). Headspace purge, followed by capillarity GC/MS analysis has been utilized for urine (Michael et al. 1980), mother s milk (Erickson et al. 1980), and tissue (Pellizzari et al. 1985). Recovery, where reported, is adequate (>60%) (Erickson et al. 1980), and detection limits are in the low-ppb range (Erickson et al. 1980). [Pg.216]

Waste water Solvent extraction optional Florisil column clean-up GC/ECD 1.34 g/L 89 Method 612 EPA 1984c... [Pg.219]

Extract with dichloromethane on chromatography column clean-up using GPC fractionation using silica gel column... [Pg.394]

Table F4.4.5 Step Gradient Conditions for C18 Column Clean-Up ... Table F4.4.5 Step Gradient Conditions for C18 Column Clean-Up ...
Fig. 44 Reverse-phase HPLC analysis of purified regioselective product triacylglycerols. Sample size 0.5-1.0 mg 5 fi C-18 column (0.49 X 50 cm) 120-min solvent gradient acetonitrile/methylene chloride (70 30 to 40 60, v/v) flow rate, 0.8 ml/min flame ionization detector. Column cleaned with methylene chloride after analysis. L, linoleic Ln, linolenic O, oleic P, palmitic S, stearic. Fig. 44 Reverse-phase HPLC analysis of purified regioselective product triacylglycerols. Sample size 0.5-1.0 mg 5 fi C-18 column (0.49 X 50 cm) 120-min solvent gradient acetonitrile/methylene chloride (70 30 to 40 60, v/v) flow rate, 0.8 ml/min flame ionization detector. Column cleaned with methylene chloride after analysis. L, linoleic Ln, linolenic O, oleic P, palmitic S, stearic.
PN after enzy- PNP with potato ODS2 (300 X Columns cleaned adjust the pH LoD = 0.2-0.4 ng/L. [Pg.436]

A Patey, M Sharman, J Gilbert. Liquid chromatographic determination of aflatoxins level in peanut butter using an immunoaffinity columns clean-up. method international collaborative trials. J Ass Off Anal Chem 74(1) 76-81, 1991. [Pg.518]

M Sharman, S Mac Donald, J Gilbert. Automated liquid chromatographic determination of ochratoxin A in cereals and animal products using immunoaffinity column clean-up. J Chiom 603 285-289, 1992. [Pg.522]

Using separation-optimized SI with 0.05 M HN03 as the eluent and 1-octanol saturated solutions, 90Sr recoveries were 96%, and carryover from one sample into a subsequent blank run was typically 1-2% 47 Blank runs or column clean-up procedures can be used to reduce or eliminate carryover between samples. Recoveries were not sensitive to elution flow rates, and columns could be used repeatedly. There were no significant performance differences between Sr-Resin materials with 20-50... [Pg.533]

Following this procedure, recovery of greater than 80% was obtained from DBA-spiked urines at levels of from 0.05 ppm to 100 ppm. The electron capture detector was linear for chloro-benzilate from 0.1 yg/ml to 2 yg/ml and for DBP from 0.005 yg/ml to 0.5 yg/ml. The lowest concentrations which produced reasonably good peak shapes (relative to noise) were 0.2 yg/ml for CB and 0.02 yg/ml for DBP. Background at the retention time of DBP averaged 0.014 ppm for control rat urines. Although this is a low value, it is highly recommended that further application of this method should include an adsorption column clean-up step such as the alumina column used by Bartsch and coworkers (3). [Pg.108]


See other pages where Columns, cleaning is mentioned: [Pg.276]    [Pg.215]    [Pg.110]    [Pg.112]    [Pg.215]    [Pg.176]    [Pg.215]    [Pg.141]    [Pg.823]    [Pg.202]    [Pg.206]    [Pg.209]    [Pg.212]    [Pg.213]    [Pg.214]    [Pg.214]    [Pg.215]    [Pg.218]    [Pg.218]    [Pg.72]    [Pg.98]    [Pg.103]    [Pg.410]    [Pg.41]    [Pg.1087]    [Pg.921]    [Pg.953]    [Pg.519]   
See also in sourсe #XX -- [ Pg.82 , Pg.210 ]




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Cleaning procedure, capillary column

Column chromatographic clean-up

Normal phase column cleaning

Reversed-phase chromatography cleaning columns

Size exclusion chromatography cleaning columns

Stationary phase column cleaning

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