A Porphyrin‐Based Conjugated Polymer for Highly Efficient In Vitro and In Vivo Photothermal Therapy

Abstract

Conjugated polymers have been increasingly studied for photothermal therapy (PTT) because of their merits including large absorption coefficient, facile tuning of exciton energy dissipation through nonradiative decay, and good therapeutic efficacy. The high photothermal conversion efficiency (PCE) is the key to realize efficient PTT. Herein, a donor-acceptor (D-A) structured porphyrin-containing conjugated polymer (PorCP) is reported for efficient PTT in vitro and in vivo. The D-A structure introduces intramolecular charge transfer along the backbone, resulting in redshifted Q band, broadened absorption, and increased extinction coefficient as compared to the state-of-art porphyrin-based photothermal reagent. Through nanoencapsulation, the dense packing of a large number of PorCP molecules in a single nanoparticle (NP) leads to favorable nonradiative decay, good photostability, and high extinction coefficient of 4.23 × 10 m cm at 800 nm based on porphyrin molar concentration and the highest PCE of 63.8% among conjugated polymer NPs. With the aid of coloaded fluorescent conjugated polymer, the cellular uptake and distribution of the PorCP in vitro can be clearly visualized, which also shows effective photothermal tumor ablation in vitro and in vivo. This research indicates a new design route of conjugated polymer-based photothermal therapeutic materials for potential personalized theranostic nanomedicine.

Electronic Tuning of Mixed Quinoidal‐Aromatic Conjugated Polyelectrolytes: Direct Ionic Substitution on Polymer Main‐Chains

“…[10,11,[16][17][18] Photothermal therapy (PTT) is ap roposed method of treating various health maladies including antibacterialresistant infections and cancer. [5,12,13,[19][20][21] PTT makes use of an active chemical agent that absorbs light and dissipates the energy as heat. Gold nanoparticles and carbon allotropes have most extensively been explored as the active agents in PTT,b ut both suffer from the lack of any known metabolic breakdown pathway and are thus assumed to be deleterious to health over long periods of time.…”

“…[21] Conjugated polymers are well-suited for use as active agents in PTT because of their relatively large molar absorption coefficients,g ood photostability,and the possibility of their biodegradability. [19,20] NIR absorbance in photothermal agents allows for accessibility deeper into tissue,a nd al ack of fluorescence in an anoxic environment indicates that nonradiative relaxation pathways are prominent. [5,[19][20][21] CPEs may be uniquely suited for use as photothermal agents because of the possibility for their water solubility and, given positively charged side-chains,t heir ability to adhere to bacterial membranes.…”

“…[19,20] NIR absorbance in photothermal agents allows for accessibility deeper into tissue,a nd al ack of fluorescence in an anoxic environment indicates that nonradiative relaxation pathways are prominent. [5,[19][20][21] CPEs may be uniquely suited for use as photothermal agents because of the possibility for their water solubility and, given positively charged side-chains,t heir ability to adhere to bacterial membranes. [5,12,13] Still, there are few examples of CPEs being used for PTT.…”

Conjugated polymer nanomaterials for theranostics

“…Moreover, CPNs with strong NIR absorption and high heat conversion efficiency have potential as a new generation of agents for PTT 87 . PDT and PTT hold great promise for non-invasive cancer treatment, and CPN-based image-guided therapy is a burgeoning area of research 87,88,89,90,91,92,93 . In addition, several new therapeutic approaches based on the mechanism of PDT and PTT have also been investigated.…”

Facile synthesis of Prussian blue nanoparticles as pH-responsive drug carriers for combined photothermal-chemo treatment of cancer

“…6,7 It has been proposed that combinating PTT with chemotherapy may induce a synergistic effect in comparison to sole treatment. 8 Subsequently, various NIR-absorbing nanomaterials, such as gold nanostructures, [9][10][11] carbon-based nanomaterials, [12][13][14][15][16] copper sulde nanoparticles, 6,17,18 palladium nanosheets, 19 transition-metal dichalcogenides nanosheets (e.g., MoS 2 , WS 2 , etc. ), 20,21 and a number of organic polymers nanoparticles, [22][23][24][25] have been developed as drug delivery vehicles for combined photothermal-chemo treatment of cancer cells.…”