Size-controlled and biocompatible Gd2 O3 nanoparticles for dual photoacoustic and MR imaging.

The synthesis, characterization, and functional evaluation of new size-controlled and biocompatible Gd(2) O(3) nanoparticles as a bimodal contrast agent for use in photoacoustic (PA) and magnetic resonance (MR) imaging are reported. These nanoparticles show a clear PA image by themselves, without conjugation with gold, rare earth metals, or dyes. Relaxivity measurement by MR imaging clearly shows that their relaxivity, r(1) , is twice that of clinically available Gd-DTPA.