Stimulated release of photosensitizers from graft and diblock micelles for photodynamic therapy

Poly(N-vinylcaprolactam), a comprehensive review on a thermoresponsive polymer becoming popular

“…In female BALB/c nude mice bearing A549 M a n u s c r i p t 70 cells xenografts, micelle-based PDT showed a better regression of tumor growth than free PPIX; effective PDT-induced inhibition of tumor growth was only observed in mice treated with pH-sensitive micelles. The role of PNVCL in this study was as an encapsulating polymer, while the copolymeric units rendered a pH sensitivity that determined the delivery potential of PPIX and ultimately its antitumor effect [237].…”

“…In PDT, the interaction between the photosensitizers and the tumor cells also affect the efficacy, as short-lived radicals generated from the photosensitizers are only toxic in close proximity to cells or tissues. To understand this effect, PNVCL grafted with poly(D,L-lactide) (PNVCL-g-PLA), a non pH-sensitive copolymer able to form micelles and poly(N-vinyl caprolactam-co-N-vinylimidazole)-g-PLA), a pH-sensitive copolymer with an endosomal ability, also able to form micelles, were synthesized and utilized for the encapsulation of protoporphyrin IX (PPIX) for in vitro and in vivo PDT studies [237]. With pH-sensitive micelles, PPIX was found in the nucleus, whereas PPIX was largely trapped in the lysosomes for the non-pH sensitive micelles.…”

Micellar Nanopreparations for Medicine

“…A number of studies have employed polymeric micelles, both targeted and non-targeted, to effectively solubilize these agents and enhance their photodynamic efficacy, simultaneously minimizing side effects. 23,114,[262][263][264][265][266] …”

Lipid- and Polymer-Based Nanostructures for Cancer Theranostics

“…In PDT, the interaction between the photosensitizers and the tumor cells also affect the efficacy, as short-lived radicals generated from the photosensitizers are only toxic to cells or tissues in close proximity. To understand this effect, (poly(N-vinyl caprolactam)-g-PLA, a pH-sensitive copolymer with endosomolytic ability, and poly(N-vinyl caprolactam-co-N-vinyl imidazole)-g-PLA), a non-pH-sensitive copolymer, were synthesized and utilized for the encapsulation of protoporphyrin IX (PPIX) for in vitro and in vivo PDT studies 75. With pH-sensitive particles, PPIX was found in the nucleus; in contrast, PPIX was largely trapped in the lysosomes for the non-pH sensitive particles.…”