Hyaluronic acid-mediated one-pot facile synthesis of a sensitive and biocompatible Gd2O3 nanoprobe for MR imaging in vivo

MR contrast agents play a crucial role in the early diagnosis of various diseases, and many nanoprobes with versatile properties have been developed. However, in order to seek high sensitivity, the biocompatibility and systemic toxicity assessment of the nanoprobes have attracted much less attention. To meet clinical requirements, it is highly desirable to develop a highly sensitive and biocompatible nanoprobe using a facile procedure. Herein, we report a sensitive and biocompatible Gd2O3 nanoprobe using hyaluronic acid (HA) via a one-pot facile synthesis. HA not only endows the nanoprobe with excellent biocompatibility, but also gives a synergistic effect for improving the sensitivity of the nanoprobe in the aspects of increasing rotational correlation time, water exchange rate and the ratio of surface Gd3+ to the inner ones. What's more, the nanoprobe has specific ability for adrenal gland MR imaging. These results suggest that the HA-Gd2O3 nanoprobe has a potentially promising application in MR imaging in vivo.