Supramolecular Phthalocyanine Assemblies for Improved Photoacoustic Imaging and Photothermal Therapy

Abstract

Phototheranostic nanoplatforms are of particular interest for cancer diagnosis and imaging‐guided therapy. Herein, we develop a supramolecular approach to fabricate a nanostructured phototheranostic agent through the direct self‐assembly of two water‐soluble phthalocyanine derivatives, PcS4 and PcN4. The nature of the molecular recognition between PcS4 and PcN4 facilitates the formation of nanostructure (PcS4‐PcN4) and consequently enables the fabrication of PcS4‐PcN4 with completely quenched fluorescence and reduced singlet oxygen generation, leading to the high photoacoustic and photothermal activity of PcS4‐PcN4. In vivo evaluations suggest that PcS4‐PcN4 could not only efficiently visualize a tumor with high contrast through whole‐body photoacoustic imaging but also enable excellent photothermal therapy for cancer.

An Ester‐Substituted Semiconducting Polymer with Efficient Nonradiative Decay Enhances NIR‐II Photoacoustic Performance for Monitoring of Tumor Growth

“…In principle, the additional exogenous agents of inorganic (carbon nanotube, gold nanorod, black phosphorus et al. ) [13] or organic (small molecules and semiconducting polymers/oligomers) [11, 14] materials with high molar‐extinction coefficient in the near‐infrared (NIR) window can greatly improve imaging contrast and resolution of objectives against self‐interference from endogenous substances, such as water, oxyhemoglobin or deoxyhemoglobin. Among them, NIR‐absorbing organic agents and their nanoparticles (NPs) have received considerable recognition in terms of their good biocompatibility, potential biodegradability, low‐cost, easy purification, and more flexibility in molecular design.…”

Self‐Assembled Nanoparticles as Cancer Therapeutic Agents

“…The PcS4‐PcN4 NPs have excellent photoacoustic and photothermal properties benefiting from completely quenching fluorescence and reducing singlet oxygen generation. [ 54 ] Specially, donor–acceptor co‐crystal system could be also applied in PTT with high photothermal conversion efficiency because the system can quench a certain level of fluorescence when the electron in donor transfers to acceptor. [ 10c ] Chen et al.…”

In Vivo Quantitative Vasculature Segmentation and Assessment for Photodynamic Therapy Process Monitoring Using Photoacoustic Microscopy

“…With PAI, anatomical structures are easily visualized, and functional information such as blood oxygenation, oxygen saturation, blood flow, and metabolism can be obtained [ 18 , 19 ]. Owing to its flexible imaging system configuration, which allows a specific resolution and penetration depth, PAI is used in various biomedical applications [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. PA computed tomography (PACT) focuses on reconstructing an image from one-dimensional radial information defining the relationship between the PA source and the detector position.…”