Abstract
Multimodal molecular imaging provides both anatomical and molecular information, aiding early stage detection and better treatment planning of diseased conditions. Here, we report development and nanotoxicity evaluation of a novel hydroxyapatite nanoparticle (nHAp) based multimodal contrast agent for combined near-infrared (NIR), MR and X-ray imaging. Under optimised wet-chemical conditions, we achieved simultaneous doping of nHAp (size ∼50 nm) with indocyanine green and Gd3+ contributing to NIR contrast (∼750–850 nm), paramagnetic behaviour and X-ray absorption suitable for NIR, MR and X-ray contrast imaging, respectively. Haematocompatibility studies using stem cell viability, haemolysis, platelet activation, platelet aggregation and coagulation time analysis indicated excellent compatibility of doped nHAp (D-nHAp). Further, the immunogenic function studies using human lymphocytes (in vitro) showed that D-nHAp caused no adverse effects. Collectively, our studies suggest that D-nHAp with excellent biocompatibility and multifunctional properties is a promising nanocontrast agent for combined NIR, MR and X-ray imaging applications.
Acknowledgement
We thank the Department of Biotechnology (DBT), Govt. of India for the financial support under the project “Nanotoxicology and Nanomedicine” (BT/PR9357/NNT/28/104/2007). We also thank the Department of Science and Technology (DST), Govt. of India for the financial support under “Nano-Theragnostics” (SR/NM/NS-99/2009). The authors also thank Dr. Rajesh Kannan, Dept. of Radiology, Amrita Institute of Medical Science, for MR measurements, Mr. Sajin P Ravi for his support in scanning electron microscopy and Mrs. Sreerekha PR for her valuable suggestions in haematotoxicity evaluation and FACS analysis.