Photothermal Properties of IR-780-Based Nanoparticles Depend on Nanocarrier Design: A Comparative Study on Synthetic Liposomes and Cell Membrane and Hybrid Biomimetic Vesicles

Abstract

Biomimetic nanoparticles hold great promise for photonic-mediated nanomedicine due to the association of the biological functionality of the membrane with the physical/chemical goals of organic/inorganic structures, but studies involving fluorescent biomimetic vesicles are still scarce. The purpose of this article is to determine how photothermal therapy (PTT) with theranostic IR-780-based nanoparticles depends on the dye content, cholesterol content, lipid bilayer phase and cell membrane type. The photophysical responses of synthetic liposomes, cell membrane vesicles and hybrid nanoparticles are compared. The samples were characterized by nanoparticle tracking analysis, photoluminescence, electron spin resonance, and photothermal- and heat-mediated drug release experiments, among other techniques. The photothermal conversion efficiency (PCE) was determined using Roper’s method. All samples excited at 804 nm showed three fluorescence bands, two of them independent of the IR-780 content. Samples with a fluorescence band at around 850 nm showed photobleaching (PBL). Quenching was higher in cell membrane vesicles, while cholesterol inhibited quenching in synthetic liposomes with low dye content. PTT depended on the cell membrane and was more efficient for melanoma than erythrocyte vesicles. Synthetic liposomes containing cholesterol and a high amount of IR-780 presented superior performance in PTT experiments, with a 2.4-fold PCE increase in comparison with free IR-780, no PBL and the ability to heat-trigger doxorubicin release.

Glycolysis inhibition for synergistic phototherapy of triple-negative breast cancer

“…The slightly higher temperature value of imLipo is ascribed to the protection of liposome to encapsulated ICG from photobleaching, which is in accordance with previous reports that the configuration of fluorescent dye in the lipid bilayer is capable of avoiding photobleaching. 40 Besides, the photothermal conversion efficiency of imLipo was 48.75% (Fig. 1(g) and (h)).…”

Immunogenic Cell Death Photothermally Mediated by Erythrocyte Membrane-Coated Magnetofluorescent Nanocarriers Improves Survival in Sarcoma Model

“…However, when incorporated in RBCm-IR-Mn, this chemotherapeutic effect is less pronounced due to the lower amount of IR-780 incorporated in the membrane ( Figure S5d ). In addition, the generation of reactive oxygen species (ROS) mediated by IR-780 under high laser power irradiation cannot be neglected [ 37 ].…”

Lipid-based nanoparticles as drug delivery carriers for cancer therapy

“…When temperatures are below the PTT, lipids normally have a more structured and well-ordered orientation (solid, gel-like phase), and when temperatures are above the PTT, they usually have a liquid-crystalline (fluid) phase ( 35 ). Adding various cholesterol concentrations can lessen the impact of PTT on liposomes ( 36 ). When high cholesterol concentrations are added at temperatures above their PTT, the liposomal bilayer becomes less elastic and leaky, thus making the liposomes more stable.…”