Centrifugate, transferring

If the samples have a large amount of particulate matter, transfer approximately 220 mL into a 250-mL centrifuge bottle, and centrifuge the contents for 10 min at 11 000 rpm. If the samples are clear or just cloudy after centrifugation, transfer 200 mL of the sample into a 250-mL graduated cylinder (or other suitable container). 

Method. Take two 20-ml screw-capped glass bottles (McCartney bottles) and to the first add 10 ml of the urine and 3 ml of hydrochloric acid, and to the second add 9 ml of blank urine, 1 ml of the reference solution, and 3 ml of hydrochloric acid. Screw on the caps and heat the bottles in a boiling water-bath for 15 minutes. Cool the solutions, add to each bottle 10 ml of petroleum spirit (b.p. 40°-60°), shake for 5 minutes, and centrifuge. Transfer the solvent layers to 10-ml conical test-tubes, evaporate to dryness under a stream of air or nitrogen, and dissolve die residues in 0.1 ml of methanol. Divide a TLC plate (silica gel G, 250 pm) into two equal columns and apply 50 pi of each exhact to die plate. Develop the plate in a tank containing a 4 1 mixture of chloroform acetone (System TD, p. 168). After development, dry die plate in a stream of cold air. 

Method. To 10 ml of urine add 1 ml of M hydrochloric acid and 10 ml of ethyl acetate, mix on a rotary mixer for 10 minutes, and centrifuge. Transfer the ethyl acetate layer to a second tube, add 10 ml of a 5% solution of lead acetate, stopper the tube, and mix gently for 1 to 2 minutes (washing with lead acetate solution removes urinary pigments from the extract). Centrifuge, transfer the solvent extract to a 15-ml conical test-tube, and evaporate to dryness under a stream of air or nitrogen. 

Pocket blotting, centrifugal transfer and vacuum or positive pressure transfer... 

Transfer the supernatants from all the microcentrifuge tubes to one new 1.5-ml microcentrifuge tube. Add another 30-pl injection buffer to each pellet, redissolve the pellet and repeat the centrifugation. Transfer these supernatants to the new tube. 

CIP system The clean-in-place skid consists of a hot water tank, centrifugal transfer pump and an air-driven diaphragm pump. Diaphragm pumps for in-Hne addition of 12.5% sodium hypochlorite, 50% citric acid and 50% sulphuric acid. 

If not already dehydrated, dry gel pieces in vacuum centrifuge. Transfer the dried slices to clean 0.6 mL tubes. 

Centrifuge the overnight culture plate at 2000 r.p.m. for 10 min in a Sorvall RT7 benchtop centrifuge. Transfer 100 pi of each culture supernatant to the appropriate well of a microtitre plate containing 20 pi of 6 x PBS containing 18% (w/v) skimmed milk powder. Mix by pipetting and leave scFv to block for 1 h at room temperature. 

Sodium hydroxide (pro analyst), 0.015 mol/L Dissolve 20g of sodium hydroxide in 20 mL of distilled water, keep in a closed flask several days and then centrifuge transfer 2 mL of the clear supernatant to 2 L of C02-free distilled water. Hie sodium hydroxide solution should be standardized against hydrochloric acid by carrying out the analysis described in Section S.4.3.2 for a distilled water sample. 

For the homogenization and transfer a total of 60ml of water is used. Add concentrated hydrochloric acid (14ml) and mix. Add benzene (70.0ml), and shake the mixture vigorously for 5 minutes. After centrifugation transfer 50ml of a O.IN heptane solution of acetic acid using a Soxhlet apparatus, distil off the solvents at a moderate rate until 5ml remain. 

Samples containing up to O.lmg of total mercury/kg. Take 50g of the sample and follow the procedure described above, only multiplying all volumes by five. This should be done up to and including the first centrifugation. Transfer 250ml of the extract to a separatory funnel and proceed according to the description for lOg samples, without changing the volumes. 

Dissolve the SnS precipitate in 1 ml of cone. HCl and oxidize with H2O. Dilute to 15 ml and add 6 drops of Fe carrier and an excess of cone. NaOH. Centrifuge. Transfer the supernate to a clean centrifuge tube, discarding the precipitate. Add 6 drops of Fe carrier, stir, and repeat centrifugation. 

Clear the supernatant by centrifuging two times at 12,000 for 10 min in a tabletop centrifuge. Transfer supernatant to a new tube each time. 

The steps of the protocol that were executed automatically were performed by a Tecan Freedom 200 robot mounted with a Biometra TRobot PCR block controlled with in-house developed software. Some of the steps were not performed robotically owing to lack of required automation equipment in our lab. Some of the DNA purifications were performed manually using a tabletop microcentrifiige owing to the lack of an automated plate centrifuge. Transfer of capillary electrophoresis and RT-PCR plates from the robot to their slots in the corresponding machinery was also performed manually due to lack of a robotic arm in our lab. 

Step 23. Dissolve the precipitate In 1 to 2 ml of IH HNO, dilute with 10 ml of HgO, and centrifuge. Transfer the super-nate to a 40-ml centrifuge tube and discard the precipitate. 

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