Fluorescent Micelles Based on Star Amphiphilic Copolymer with a Porphyrin Core for Bioimaging and Drug Delivery

Abstract

Star-shaped poly(ε-caprolactone)-b-poly(ethylene oxide) amphiphilic copolymer with a tetrakis-(4-aminophenyl)-terminated porphyrin core was synthesized. Paclitaxel (PTX)-loaded polymeric micelles were prepared by the self-assembly of the star copolymer and in situ encapsulation of PTX. The fluorescent characteristic of the porphyrin moiety allowed the cellular uptake and biodistribution of the PTX-loaded micelles to be monitored by fluorescent imaging. The PTX-loaded micelles can be readily internalized by cancer cells and have a slightly higher cytotoxicity than clinic PTX injection Taxol. In vivo real-time fluorescent imaging revealed that the micelles could accumulate at tumor site via the blood circulation in tumor-bearing mice. In vivo antitumor efficacy examinations indicated that the PTX-loaded micelles had significantly superior efficacy in impeding tumor growth than Taxol and low toxicity to the living mice.

Star‐Shaped Polymer Consisting of a Porphyrin Core and Poly(L‐lysine) Dendron Arms: Synthesis, Drug Delivery, and In Vitro Chemo/Photodynamic Therapy

“…The diameter determined by TEM was smaller than that by DLS due to the shrinkage in dry state. [ 33 ] It is reported that cells typically uptake particles ranging from about 50 to several hundred nanometers, [ 34 ] so it was confi rmed that the obtained PP-PLLD/DOX complex was within the size requirements for effi cient cellular endocytosis. bands respectively.…”

Soft fluorescent nanomaterials for biological and biomedical imaging

“…Based on the EPR effect, fluorescent PEO-stabilized drug-loaded micelles were used to image drug delivery via the blood circulation in tumor-bearing mice. 114 The real-time fluorescent imaging revealed that the micelles accumulated at tumor site until they reach a maximum level at 24h post-injection; they then were slowly cleared from the tumor. Although EPR-based passive targeting is easy to carry out, active targeting exhibits better specificity with the established ligand-receptor interactions.…”

“…110 Several fluorescent polymeric micelles have been prepared from dye-conjugated amphiphilic block copolymers 111, 112 or hyperbranched star copolymers. 113, 114 In a typical study, PEGylated copolymers were conjugated with the NIR dye ICG and the ligand folate; the self-assembled polymeric micelles were about 150 nm in hydrodynamic size and 40-60 nm in the solid state. 115 During the self-assembly process, additional small hydrophobic species can be simultaneously encapsulated into the particle core to create multi-colored fluorescent imaging agents.…”

“…115 During the self-assembly process, additional small hydrophobic species can be simultaneously encapsulated into the particle core to create multi-colored fluorescent imaging agents. 111, 113, 114 …”

“…Therefore, nonspecific in vitro imaging is an elementary step for showing cellular images labeled with soft fluorescent NPs. A lot of fluorescent organic NPs have been used to label cells, including fluorescent conjugated polymer NPs, 53, 75, 106 dye-doped polymeric NPs, 58, 66, 78, 129 AIE- 126 and DIE- 108 type small-molecule NPs, self-fluorescent biodegradable NPs 69 and phototunable NPs 110, 114 .…”