Tailoring Iridium Luminescence and Gold Nanoparticle Size for Imaging of Microvascular Blood Flow

Abstract

Aim:Imaging of blood flow in narrow channels and close to vessel walls is important in cardiovascular research for understanding pathogenesis. Our aim was to provide novel nanoprobes with visible emission and long lifetimes as trackers of flow. Materials & methods: Gold nanoparticles coated with an iridium complex were prepared. Luminescence imaging was used to monitor their flows in different hematocrit blood and in murine tissues. Results: The velocities are independent of hematocrit level and the nanoparticles entering blood circulation can be clearly detected in vessels in lungs, mesentery and the skeletal muscle. Conclusion: The work introduces for the first time iridium-based yellow-green luminescence with nanoparticle size of 100 nm for visualizing and monitoring flows with much higher resolution than conventional alternatives.

Assisted delivery of anti-tumour platinum drugs using DNA-coiling gold nanoparticles bearing lumophores and intercalators: towards a new generation of multimodal nanocarriers with enhanced action

“…49 Nevertheless, the toxicity of each of the drug conjugates is higher than that of the carriers alone. The design offers potential to but does not yet include additional targeting vectors for specic cells or tissues, 4,[25][26][27][28][29] but would potentially benet from gold nanoparticle enhanced permeability and retention in vivo.…”

“…5,[19][20][21][22][23][24] Gold nanoparticles (GNPs) have been shown to be versatile drug-delivery platforms for different drugs, allowing easy conjugation procedures and the possibility of co-loading different functionalizing units, such as targeting vectors or imaging probes to modify and control biodistribution. 4,[25][26][27][28][29] In addition, GNPs are themselves biocompatible, non-toxic and inert; their size and dispersity is easy to control and small GNPs efficiently penetrate cell membranes and can be monitored inside cells using a variety of modalities. [30][31][32] Anionic nanoparticles are perceived to be advantageous for drug delivery, as cationic nanoparticles can disrupt membranes in the cell.…”

Polymer Therapeutics: Biomarkers and New Approaches for Personalized Cancer Treatment

“…A recent study from Rogers et al demonstrated the utility of 100 nm iridium-labelled gold nanoparticles to track the flow of blood through micrometer-sized blood vessels in normal mouse tissues using luminescence imaging [ 91 ]. The potential for in vivo high-resolution visualization and monitoring of blood flow based on small fluorescently labelled nanoparticles in cancer patients could provide valuable biomarker data on the potential for passive targeting and pharmacokinetic parameters.…”

Gold Nanoparticles in Conjunction with Nucleic Acids as a Modern Molecular System for Cellular Delivery

“…Mentioned above optical properties became of interest in the field of bioimaging, where AuNPs serve as probes to visualize cellular compartments and allow to follow nanoparticles' cellular uptake, specificity and locations, which might be used for the targeted therapies [26,35,36]. In the greater scale, AuNPs were shown to aid mapping of lymph nodes [37], or vascular blood flow [38]. AuNPs are also used as a tool for cancer imaging and/or a core element for the specific mRNA, creating a dual probe to screen for melanoma, prostate or carcinoma cancer cells, and circulating breast cancer cells [39] and brain tumors [40].…”