Resin Shaking

Assay Solution Transfer 0.1 g of sample, accurately weighed, into a 100-mL volumetric flask, and dilute to volume with deionized water. Transfer approximately 10 mL of this solution into a separate container, and add approximately 0.2 g of an MB-1 mixed-bed resin. Shake this mixture for 30 s, and filter through a 0.45-micron nylon disc filter. 

Place about 30 g of the cation exchange resin in a conical flask. Add about 25 ml of ethanol, shake the stoppered flask for about 1 minute, remove the ethanol by decantation and repeat the operation with a further 20 ml of ethanol. Transfer 25 ml of the fusion product extract to the resin, shake for about 5 minutes and decant the solution into a suitable conical titration flask containing a magnetic stirrer bar. Rinse the... 

Remove the solution and wash the resin with DMF (add 2 mL for 100 mg of resin, shake for 5 min, remove the solvent, and repeat the whole procedure five times). 

Remove the solvent by filtration and wash the resin consecutively with dry NMP and dry DCM (add 3 mL for 100 mg of resin, shake for 10 min, remove the solvent, repeat the whole procedure five times for each solvent) and with anhydrous THF (add 3 mL for 100 mg of resin, shake for 5 min, remove the solvent, repeat the whole procedure three times for each solvent—see Note 26). 

---