Photocontrollable release and enhancement of photodynamic therapy based on host–guest supramolecular amphiphiles

Abstract

A light-controlled porphyrinic photosensitizer release system was developed based on host-guest TPP-Azo/PEG-b-CD supramolecular amphiphiles, which could significantly enhance the efficiency of photodynamic therapy. TPP-Azo was prepared via esterification between TPP and Azo derivatives, and further used to construct supramolecular amphiphiles with PEG-b-CD. TEM images showed that TPP-Azo/PEG-b-CD amphiphiles can self-assemble into spherical micelles, and then disaggregate under irradiation with 365 nm UV light. The phototoxicity and bio-distribution of TPP-Azo/PEG-b-CD micelles against the MCF-7 cell line were also evaluated by MTT assay, flow cytometry and confocal scanning laser microscopy, respectively. According to MTT assay, the IC 50 of the spherical micelle was 31.2 mg mL À1 , but it became 20.6 mg mL À1 upon pre-irradiation with 365 nm UV light. This shows for the first time that UV light can well stimulate the release of porphyrin photosensitizers and improve the photodynamic therapy efficiency based on the system of host-guest supramolecular amphiphiles.

Dynamic Macromolecular Material Design—The Versatility of Cyclodextrin‐Based Host–Guest Chemistry

“…The amphiphilic nature of the complex resulted in micelles being formed with a cmc of 5.9 mg L −1 and radii of 43 nm. A similar approach was undertaken with an azobenzene guest group, which led to photoresponsive micelles being obtained . A β‐CD‐centered PLA 21‐arm star was grafted with POEGMA to obtain an amphiphilic block copolymer that formed micelles for delivery of DOX with a cmc of 3.1 mg L −1 and radii of 37 nm.…”

“…As imilar approach was undertaken with an azobenzene guest group, which led to photoresponsive micelles being obtained. [110] A b-CD-centered PLA 21-arm star was grafted with POEGMA to obtain an amphiphilic block copolymer that formed micelles for delivery of DOX with ac mc of 3.1 mg L À1 and radii of 37 nm. AP DMA-b-PNIPAM-b-PDMA triblock copolymer with adamantyl units in the PDMA block was utilized by Becer and co-workers.…”

Self‐Amplified Photodynamic Therapy through the 1O2‐Mediated Internalization of Photosensitizers from a Ppa‐Bearing Block Copolymer

“…Owing to the non‐invasive nature and the potential of precise spatiotemporal control, a range of photo‐responsive systems have been engineered using exogenous light irradiation . However, most of photochromic moieties, such as azobenzene, suffer from various drawbacks, such as low penetration depth and skin injury because of the harmful UV light response. Although upconverting nanoparticles (UCNPs) have been proposed to convert near infrared (NIR) light to UV light to overcome this limitation, the low energy conversion efficiency and expensive cost still exist in treatments.…”

“…[15] To release PSs at the tumor sites,e xogenous stimuli-responsive PS delivery systems also have been constructed, such as thermo- [16] and light- [17] sensitive nanoparticle systems.O wing to the non-invasive nature and the potential of precise spatiotemporal control, ar ange of photo-responsive systems have been engineered using exogenous light irradiation. [18] However,most of photochromic moieties,s uch as azobenzene, [19] suffer from various drawbacks,s uch as low penetration depth and skin injury because of the harmful UV light response.A lthough upconverting nanoparticles (UCNPs) [20] have been proposed to convert near infrared (NIR) light to UV light to overcome this limitation, the low energy conversion efficiencya nd expensive cost still exist in treatments. 1 O 2 is extremely reactive and can react with electron-rich olefins,s uch as vinyldithioether,t or elease photosensitizers,w hich could enhance PDT or activate fluorescence emission.…”

Fabrication of a Dual‐Stimuli‐Responsive Supramolecular Micelle from a Pillar[5]arene‐Based Supramolecular Diblock Copolymer for Photodynamic Therapy

“…Nowadays, host–guest interaction is recognized as one of the most important classes of noncovalent interactions and is extensively utilized to build supramolecular polymers . To date, a variety of supramolecular polymers are widely applied to construct supramolecular polymeric nanoparticles such as vesicles and micelles, which exhibit great advantages in cancer therapy . For example, Yuan and co‐workers reported a voltage responsive vesicle built by two end‐decorated homopolymers via host–guest interaction .…”