Abstract
Although various types of imaging agents have been developed for photoacoustic (PA) imaging, relatively few imaging agents exhibit high selectivity/sensitivity to the tumor microenvironment for on-demand PA imaging and therapy. Herein, molybdenum-based polyoxometalate (POM) clusters with the highest oxidation state of Mo(VI) (denoted as Ox-POM) were designed as novel agents for redox-activated PA imaging-guided photothermal therapy. Capable of escaping from recognition and capture by the liver and spleen, these renal clearable clusters with ultrasmall size (hydrodynamic size: 1.9 nm) can accumulate in the tumor, self-assemble into larger nanoclusters at low pH, and are reduced to NIR absorptive agents in the tumor microenvironment. Studies in 4T1 tumor-bearing mice indicated that these clusters could be employed for bioresponsive PA imaging-guided tumor ablation in vivo. Our finding is expected to establish a new physicochemical paradigm for the design of PA imaging agents based on clusters, bridging the conventional concepts of “molecule” and “nano” in the bioimaging field.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 3282-3289 |
| Number of pages | 8 |
| Journal | Nano letters |
| Volume | 17 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 10 2017 |
Funding
This work was supported, in part, by the University of Wisconsin-Madison, the National Institutes of Health (NIBIB/NCI 1R01CA169365, 1R01EB021336, P30CA014520, S10-OD018505, T32GM008505), and the American Cancer Society (125246-RSG-13-099-01-CCE).
Keywords
- Redox-responsive probes
- photoacoustic imaging
- photothermal therapy
- polyoxometalate cluster
- theranostic agent
ASJC Scopus subject areas
- Condensed Matter Physics
- Mechanical Engineering
- Bioengineering
- General Chemistry
- General Materials Science
