Nanoparticles of N-Vinylpyrrolidone Amphiphilic Copolymers and Pheophorbide a as Promising Photosensitizers for Photodynamic Therapy: Design, Properties and In Vitro Phototoxic Activity
Open accessAbstract
A series of nanoparticles (NPs) with a hydrodynamic radius from 20 to 100 nm in PBS was developed over the solubilization of hydrophobic dye methyl pheophorbide a (chlorin e6 derivative) by amphiphilic copolymers of N-vinylpyrrolidone with (di)methacrylates. Photophysical properties and biological activity of the NPs aqueous solution were studied. It was found that the dye encapsulated in the copolymers is in an aggregated state. However, its aggregation degree decreases sharply, and singlet oxygen quantum yield and the fluorescence signal increase upon the interaction of these NPs with model biological membranes—liposomes or components of a tissue homogenate. The phototoxic effect of NPs in HeLa cells exceeds by 1.5–2 times that of the reference dye chlorin e6 trisodium salt—one of the most effective photosensitizers used in clinical practice. It could be explained by the effective release of the hydrophobic photosensitizer from the NPs into biological structures. The demonstrated approach can be used not only for the encapsulation of hydrophobic photosensitizers for PDT but also for other drugs, and N-vinylpyrrolidone amphiphilic copolymers show promising potential as a modern platform for the design of targeted delivery vehicles.
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Nanoparticles of N-vinylpyrrolidone amphiphilic copolymers and Pha from Spirulina sp. had in vitro phototoxic effect in HeLa cells exceeding that of chlorin e6 trisodium salt by 1.5-2 times under red light.
“Nanoparticles of N-vinylpyrrolidone amphiphilic copolymers and Pha processed from Spirulina sp. were evaluated as promising PSs; when irradiated with red light (λ = 660 nm), the in vitro phototoxic effect of the nanoparticles in HeLa cells exceeded by 1.5–2 times that of the reference dye chlorin e6 trisodium salt—one of the most effective PSs used in clinical practice [141].”
From Emerging Applications of Chlorella sp. and Spirulina (Arthrospira) sp. (2023) · cites this paper as [141]
The Conclusions report that the nanoparticles’ photodynamic activity in HeLa cells exceeded that of chlorin e6 by 1.5–2 times, and Methods §2.1 says the dye was derived from Spirulina. However, Methods §2.7 specifies that the HeLa cells were irradiated with light at λ > 630 nm, not specifically 660 nm; the nanoparticles contained methylpheophorbide a rather than unmodified pheophorbide a. Results §3.6 also reports higher phototoxic IC50 values for the nanoparticles than for chlorin e6, creating an inconsistency with the stated comparison. (LLM, conf=0.88)
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- Authors
- Rybkin, A. Y., Kurmaz, S. V., Urakova, E. A., Filatova, N. V., Sizov, L. R., Kozlov, A. V., Koifman, M. O., & Goryachev, N. S.
- Affiliations
- Russian Academy of Sciences (RU)
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry, Russian Academy of Sciences, Pr. Akademika Semenova 1, 142432 Chernogolovka, Russia
- Department of Chemistry and Technology of Macromolecular Compounds, Ivanovo State University of Chemistry and Technology, Sheremetevskiy Av. 7, 153000 Ivanovo, Russia
- Corresponding author
- Rybkin, Alexander Yu.
- Venue
- Pharmaceutics
- Publisher
- MDPI AG
- Published
- 2023-01-12
- Volume
- 15
- Issue
- 1
- Pages
- 273
- ISSN
- 1999-4923 (ISSN-L)
- PMC
- PMC9863766
- OpenAlex
- W4316039951
- Cited by
- 20
- References
- 48
- Citations by year
- 2026: 3 · 2025: 6 · 2024: 7 · 2023: 4
- FWCI
- 3.67
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- Pharmaceutics (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Ministry of Science and Education of the Russian Federation (AAAA-A19-119071890015-6, AAAA-A19-119112590105-7)
- Topics
- Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Photodynamic Therapy Research Studies
- Physical Sciences › Engineering › Biomedical Engineering › Nanoplatforms for cancer theranostics
- Physical Sciences › Materials Science › Biomaterials › Nanoparticle-Based Drug Delivery
- Keywords
- N-vinylpyrrolidone copolymers, amphiphilic copolymers, pheophorbide a, methyl pheophorbide a, chlorin e6 derivatives, photosensitizers, photodynamic therapy, nanoparticles, drug encapsulation, singlet oxygen quantum yield, phototoxicity, HeLa cells, liposomes, targeted drug delivery, photophysical properties
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