2-Butanone, 5ml

(1R,2R,5S,6S)-1,2,5,6-Tetrabromocyclooctane, 1.2ml x 50ug/ml , toluene

25-Hydroxyvitamin D2-d6, 50µg/ml in MeOH, 1ml

o-Toluidine,100 µg/mL,acetonitrile,1mL,