Vortex glass phase

Lipid extraction 200 pL of plasma sample is mixed by brief vortexing with 200 pL of ethanol followed 1 min of vortexing with 800 pL hexane. After centrifugation for 5 min at 5000 rpm, 400 pL of upper (hexane) phase is transferred to a glass tube with screwed cap, dried under nitrogen, and kept at - 60°C until PCL analysis. For PCL analysis the sample is dissolved in 400 pL of MeOH by 30 s of vortexing, and 100 pL aliquots are taken for ACL assay. 

In the method, soil samples are extracted by shaking or vortexing with the solvent. Water samples are extracted by shaking in a separatory funnel. If there is a potential for the presence of compounds that interfere with the method and make the data suspect, silica gel can be added to clean the extract. Sample extract aliquots are placed close to the bottom of a glass plate coated with a stationary phase. The most widely used stationary phases are made of an organic hydrocarbon moiety bonded to a silica backbone. 

An aliquot of 250 pi of plasma to be analysed and 250 pi of the standard solution were pipetted in an 11.5 ml glass tube. Then, 250 pi of acetate buffer solution was added and mixed for ten seconds on a vortex mixer. 9 ml of extraction liquid was added and the solution in the tubes was extracted on a Heidolph tumble mixer. A potential problem is present if the solvents used are mixed in different compositions a composition can possibly be selected that has a density equal to the density of the aqueous layer. This may give rise to problems with the phase separation. 

Add 1 ml dichloromethane (DCM) to extract the alditol acetates. Vortex to mix (do not cap the tubes, as the glue holding Teflon liners may be soluble in DCM). Allow the phases to separate and transfer the lower DCM phase to a clean borosilicate glass tube using a Pasteur pipet. 

Sample preparation 1 mL Plasma + 50 jiL 10 pg/mL nisoldipine in MeOH + 100 (xL 1 M NaOH, vortex for 3 s, add 5 mL 75 25 MTBE isooctane, vortex for 30 s, centrifuge at 1800 g for 5 min. Transfer upper layer to a 100 X 13 mm glass tube, evaporate to dryness without heating using a Speed Vac concentrator evaporator. Reconstitute in 200 p,L mobile phase, vortex for 15 s, inject a 150 p,L aliquot. 

The experiments were carried out in a stirred cell reactor. The operation was batch-wise with respect to the liquid phase. The stirred cell reactor constructed from resistant glass with interfacial area for mass transfer of 76.93 cm. The internal diameter of the reactor was 10 cm with a total volume of about 1800 cm. The gas and liquid phases were stirred separately using two stirrers. To prevent the formation of vortex, four equidistant baffles were placed inside the reactor. An infrared Rosemount model 880A CO2 analyzer was used to measure the amount of carbon dioxide at the exit of the reactor. 

Sample preparation Mix 2 mL serum with 10 irL 10 (xg/mL IS in MeOH, add 200 jxL concentrated ammonium hydroxide, add 5 mL dichloromethane, shake on a reciprocating shaker for 30 min, centrifuge at 730 g for 20 min. (If excessive emulsion is present, mix by inversion and centrifuge again.). Evaporate the organic layer to dryness in a silanized glass tube under a stream of nitrogen below 40°, reconstitute the residue with 80 pL mobile phase, vortex, inject a 25 pL aliquot. 

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