Cartridge column

Sample extracts are cleaned up with a cartridge column before the acetylation of E-2 to E-16 and of E-1 to E-15. The final cleanup, plant material and soil samples are analyzed by gas chromatography (GC)/MSD. The GC/NPD method is applicable to water samples. 

Adjust to pH 2 by addition of concentrated HCl to 500 mL of water sample. Apply this acidic water to the Bond Elut LRC Cig (500-mg) cartridge column. Pass the elution solvent (2 mL of acetonitrile) through the cartridge and collect in a test-tube. Concentrate the eluate under an N2 gas flow at about 40 °C. 

Pass 0.5 mL of the suspended acetone solution through the Bond Elut SCX (100-mg) cartridge and collect in an Eppendorf tube. Wash the cartridge column with two portions of 0.5 mL of acetone and combine all of the eluates (total volume ca 1.5 mL). This step is omitted for water. 

Add 2 X 0.5 mL of n-hexane-ethyl acetate (9 1, v/v) to the residue and apply to the Bond Elut SI (100-mg) cartridge column. Pass the elution solvent [1 mL of n-hexane-ethyl acetate (3 2, v/v)] through the cartridge and collect in an Eppendorf tube. Concentrate the eluate under an N2 gas flow at about 40 °C and dissolve the residue in 0.5 mL of acetone. Dilute an aliquot of the acetone solution twofold with acetone and adjust the amount of impurities in both the standard and sample solutions for high reliability of GC analyses [details are shown in Section 3.3.4(1)]. 

Cartridge column chromatography (rice grain and rice straw)... 

Measure a 1000 mL aliquot of sample solution and transfer to the top of the Cig SPE cartridge column which was conditioned with 5 mL of ethyl acetate, 5 mL of methanol and 10 mL of distilled water in advance at an elution rate of 10 mL min . After washing the column with 10 mL of distilled water, dry the column with suction for 30 min, then elute with 0.5 mL of acetone and then 5 mL of ethyl acetate. Dry the eluates using a rotary evaporator at 35 °C and by N2 purging. 

SPE cartridge column Mega Bond Elut Cig, lO-g/60-mL (Varian). The SPE cartridge column is rinsed with 100 mL of methanol and 100 mL of distilled water Rotary vacuum evaporator, 40 °C bath temperature Water-bath, electrically heated, temperature 80 °C Mechanical shaker (universal shaker)... 

Multiple choice of media and phases (including cartridges, columns and discs)... 

Column systems are basically classified into two groups conventional and cartridge columns. A conventional column usually demonstrates better column efficiency than does a cartridge column due to a higher column packing pressure, but its usefulness depends on the quality control system of the manufacturer and the skill of their technicians. A cartridge column is economical, but its theoretical performance and lifetime can be less than a conventional column. 

Aspirin and salicylic acid were eluted with a mobile phase of aqueous acetonitrile, acidified to pH 2.6, using orthophosphoric acid, at a flow rate of 1.5 ml/min. A UVA is detector was employed with a wavelength of 295 nm, 0.1 aufs sensitivity and a response time of 0.5sec. A 25 cm x 4 mm Lichrocart Cl 8 cartridge column with a guard column of the same material was used and the column temperature was maintained at 40 °C. 

Fig. 45 Reversed-phase HPLC of autoxidized trilinolenin (peroxide value = 236.4 meq/kg). Nova-Pak C18 cartridge column (Waters, Milford, MA) (3.9 X 150 mm, 60 A, 4 yam), mobile phase acetonitrile/ dichloromethane/methanol (80 10 10). Ultraviolet (UV) detector (235 nm) and evaporative light-scattering detector (ELSD). Primary oxidation products, double peak at 3.6 min secondary oxidation products elute before primary oxidation products.

Table 2 Recoveries of Various Lipid Classes (in %) After SPE Using Bond Elut-Aminopropyl Disposable Cartridge Column...

Imazalil, OPP, and TBZ residues were determined using an HPLC system, consisting of a ternary HPLC pump attached to 250 X 4.6-mm-ID Hichrom RPB 5-/tm column with a 10 X 3.2-mm-ID guard cartridge column. The packing material of both columns was base-deactivated silica, fully endcapped with a bonded phase of Cg/C]8. The mobile phase was methanol/water at a flow rate of 1 ml/min at ambient temperature. Imazalil in the eluate was detected with UV detector at 204 nm a fluorescence detector was used to monitor OPP (excitation 285 nm, emission 350 nm) and TBZ (excitation 296 nm, emission 350 nm) (47). 

Preconcentration on Cl 8 cartridge column, elution with MeOH, H,0. Dilution. pH adjustment to 2.1-2.6 with H2S04. Na2S204 addition. pH adjustment to 8.5 with NaOH. NaCl addition, CHCI3 extraction, H2S04 addition, diazoti-zation and coupling reaction with disodium-2-naphthol-3,6-disulfonate. Dissolution in MeOH. 

Cartridge columns consist of 0.5-1 g of 40- m particles sandwiched between 30-jUm frits. The column s body may be a tube shrunk around a sandwich of bed support frits and packing. In another type, the frits and packing may be pushed into a small syringe barrel. The 0.5-g SFE has a sample capacity of about 25 mg and a void volume of about 1.5 mL. 

You decide to do windowing on a C18 SFE cartridge column. You take a mixture of the four original standards, dilute it 5-fold with water to increase the compound s k s, and pass it through the MeOH and water-wetted SPE... 

Cartridge Column—Disposable off-line tube packed with >1 g of packing used for sample and solvent preparation. (See SFE and Windowing.)... 

SFE—Separation and filtration cartridge column. Also referred to as a SPE (solid phase extraction column). (See windowing in Chapter 12.)... 

Windowing—A technique using cartridge columns (SFE) to speed chromatography by first removing polar and nonpolar impurities, leaving only a solvent fraction containing the compounds of interest. 

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