Improved anticancer efficacy of methyl pyropheophorbide-a–incorporated solid lipid nanoparticles in photodynamic therapy

Abstract

Photodynamic therapy (PDT) is a promising anticancer treatment because it is patient-friendly and non-invasive. Methyl pyropheophorbide-a (MPPa), one of the chlorin class photosensitizers, is a drug with poor aqueous solubility. The purpose of this study was to synthesize MPPa and develop MPPa-loaded solid lipid nanoparticles (SLNs) with improved solubility and PDT efficacy. The synthesized MPPa was confirmed 1H nuclear magnetic resonance (1H-NMR) spectroscopy and UV–Vis spectroscopy. MPPa was encapsulated in SLN via a hot homogenization with sonication. Particle characterization was performed using particle size and zeta potential measurements. The pharmacological effect of MPPa was evaluated using the 1,3-diphenylisobenzofuran (DPBF) assay and anti-cancer effect against HeLa and A549 cell lines. The particle size and zeta potential ranged from 231.37 to 424.07 nm and − 17.37 to − 24.20 mV, respectively. MPPa showed sustained release from MPPa-loaded SLNs. All formulations improved the photostability of MPPa. The DPBF assay showed that SLNs enhanced the 1O2 generation from MPPa. In the photocytotoxicity analysis, MPPa-loaded SLNs demonstrated cytotoxicity upon photoirradiation but not in the dark. The PDT efficacy of MPPa improved following its entrapment in SLNs. This observation suggests that MPPa-loaded SLNs are suitable for the enhanced permeability and retention effect. Together, these results demonstrate that the developed MPPa-loaded SLNs are promising candidates for cancer treatment using PDT.

Sulconazole-Loaded Solid Lipid Nanoparticles for Enhanced Antifungal Activity: In Vitro and In Vivo Approach

“…Our findings showed that the amount of GMS as a lipid directly correlates with the size of the particles. Similar findings were interpreted by Sooho Yeo et al [23]. The optimized SCZ-SLN2 zeta potential values were discovered to be −26.98 mV.…”

A Physiochemical, In Vitro, and In Vivo Comparative Analysis of Verteporfin–Lipid Conjugate Formulations: Solid Lipid Nanoparticles and Liposomes

“…LNPs containing glycerol monostearate and poloxamer 188 exhibited the highest PDT efficiency and stability with an average hydrodynamic diameter of 284.90 nm and ζ-potential of −23.33 mV. 21 …”

“…LNPs containing glycerol monostearate and poloxamer 188 exhibited the highest PDT efficiency and stability with an average hydrodynamic diameter of 284.90 nm and ζ-potential of −23.33 mV. 21 With regards to lipid formulations of BPD, Michy et al developed LNPs containing BPD. They demonstrated that LNPs containing BPD improved PDT efficacy in ovarian cancer, as compared to the unformulated photosensitizer.…”

“…Recently, LNPs have been approved as mRNA delivery vehicles in vaccines developed for COVID-19, and a Nobel Prize was awarded in 2023 for pioneering work on LNP-based vaccines . While existing research has primarily focused on LNP applications in drug delivery and vaccine technologies, only a few studies have investigated the potential for LNPs as effective photosensitizer delivery platforms for PDT. − Sohoo et al encapsulated methyl pyro­pheophorbide-a (MPPa), a hydrophobic photosensitizer, in LNPs and demonstrated an increase in water solubility of the photosensitizer and an improvement in PDT efficacy. They used a combination of different lipids (palmitic acid, steric acid, and glycerol monostearate) and surfactants (poloxamer 188, poloxamer 488, and tween 80) to synthesize and compare ten different formulations loaded with MPPa.…”

“…They used a combination of different lipids (palmitic acid, steric acid, and glycerol monostearate) and surfactants (poloxamer 188, poloxamer 488, and tween 80) to synthesize and compare ten different formulations loaded with MPPa. LNPs containing glycerol monostearate and poloxamer 188 exhibited the highest PDT efficiency and stability with an average hydrodynamic diameter of 284.90 nm and ζ-potential of −23.33 mV …”