Eichrom's TRU Resin is an extraction chromatographic material in which the extractant system is octylphenyl-N,N-di-isobutyl carbamoylphosphine oxide (abbreviated CMPO) dissolved in tri-n-butyl phosphate (TBP). The bed density of TRU Resin is approximately 0.37 g/mL, with a working capacity of 2 mg Am per mL of resin or 4 mg Am per 2mL pre-packed column. This value represents 20% of the theoretical maximum loading capacity of the resin.