Figure 2.

A plot of the starting ²²⁵Ac activity used to radiolabel vs the final specific activity. The multiple copies of DOTA chelate covalently appended to the SWCNT scaffold (filled black squares) permit amplification of the amount of radioactivity that can be loaded onto the targeting construct relative to 2 different IgG-DOTA constructs (lintuzumab [filled red circles] and E4G10 [filled blue circles]). The nonlinear regression fitted curve (dashed black line) is shown for the SWCNT-DOTA labeling data.

Abbreviations: ²²⁵Ac, actinium-225; DOTA, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; SWCNT, single wall carbon nanotube; IgG, immunoglobulin G.