Delivery of Phosphorescent Anticancer Iridium(III) Complexes by Polydopamine Nanoparticles for Targeted Combined Photothermal‐Chemotherapy and Thermal/Photoacoustic/Lifetime Imaging

Abstract

Recently, phosphorescent iridium complexes have demonstrated great potential as anticancer and imaging agents. Dopamine is a melanin‐like mimic of mussel adhesive protein that can self‐polymerize to form polydopamine (PDA) nanoparticles that demonstrate favorable biocompatibility, near‐infrared absorption, and photothermal effects. Herein, PDA nanoparticles are functionalized with β‐cyclodextrin (CD) substitutions, which are further assembled with adamantane‐modified arginine‐glycine‐aspartic acid (Ad‐RGD) tripeptides to target integrin‐rich tumor cells. The thus formed PDA‐CD‐RGD nanoparticles can deliver a phosphorescent iridium(III) complexes LysoIr ([Ir(ppy)2(l)]PF6, ppy = 2‐phenylpyridine, L = (1‐(2‐quinolinyl)‐β‐carboline) to form a theranostic platform LysoIr@PDA‐CD‐RGD. It is demonstrated that LysoIr@PDA‐CD‐RGD can be applied for targeted combined cancer photothermal‐chemotherapy and thermal/photoacoustic/two‐photon phosphorescence lifetime imaging under both in vitro and in vivo conditions. This work provides a useful strategy to construct multifunctional nanocomposites for the optimization of metal‐based anticancer agents for further biomedical applications.

UV‐Triggered Polydopamine Secondary Modification: Fast Deposition and Removal of Metal Nanoparticles

“…Therefore, over the past decade, PDA coatings have been widely used to construct functional surfaces with biocompatibility, conductivity, antibacterial/antifouling properties and superhydrophobicity, on various substrates and interfaces. PDA coating has also been employed in drug delivery, wound healing, thermal therapy, organic catalysis, and so on, due to its properties such as nontoxicity, self‐healing, NIR responsibility, and electron transfer property …”

Anticancer IrIII–Aspirin Conjugates for Enhanced Metabolic Immuno‐Modulation and Mitochondrial Lifetime Imaging

“…Since iridium complexes have environment‐sensitive long phosphorescence lifetimes, time‐gate imaging can be used to reduce the interference of background fluorescence . More importantly, the PLIM technique can be advantageously applied to phosphorescent metal complexes to accurately reflect changes in microenvironments . After treatment for 4 h, the cellular lifetimes of Ir2 and Ir3 gradually increased (Figure B, D).…”

“…[14] More importantly,t he PLIM technique can be advantageously applied to phosphorescent metal complexes to accurately reflect changes in microenvironments. [45,46] After treatment for 4h, the cellular lifetimes of Ir2 and Ir3 gradually increased (Figure 3B,D ). The lifetime of Ir2 was extended from 240 ns to 388 ns, and that of Ir3 was extended from 300 ns to 360 ns.…”

Effects of Programmed Local Delivery from a Micro/Nano‐Hierarchical Surface on Titanium Implant on Infection Clearance and Osteogenic Induction in an Infected Bone Defect

“…Meanwhile, the porous structure could contain more newly formed bone tissue and build the mechanical interlocking . It was reported that AH‐treated Ti surface and PDA membrane could promote cell adherent behavior through integrin signaling pathway . Besides, Sr 2+ stimulates calcium sensitive receptors and activates PI3K‐Akt, Wnt/β‐catenin signaling pathway to enhance bone formation .…”