Abstract
The enantiomeric purity of commercial L-[U-14C]valine was determined. The process involved sequential dilution with nonradioactive DL-valine, N-dansylation using dansyl chloride, and resolution using reversed-phase thin-layer chromatography in the presence of σ-cyclodextrin, a chiral mobile phase additive. Liquid scintillation counting of the bands corresponding to DNS-D- and L-valine gave the enantiomeric purity, as well as the percent radiochemical yield. Because the derivatization reaction proceeded without racemization, the results corresponded to the relative amounts of radioactive D- and L-valine in the commercial sample. The analyses were easily performed using less than 1 µ Ci of L-[U-14C]valine per pair of students. This laboratory experiment provides students with valuable experience in handling radioisotopes, illustrates the use of liquid scintillation counting as a sensitive detection method, reinforces important stereochemical relationships, and can be applied to the analysis of other rad...
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
