PLGA nanoparticles as delivery systems for protoporphyrin IX in topical PDT: cutaneous penetration of photosensitizer observed by fluorescence microscopy

• Published in: Journal of nanoscience and nanotechnology Vol. 13; no. 10; p. 6533
• Main Authors: da Silva, Carolina Loureiro, Del Ciampo, José Orestes, Rossetti, Fábia Cristina, Bentley, Maria Vitória Lopes Badra, Pierre, Maria Bernadete Riemma
• Format: Journal Article
• Language: English
• Published: United States 01.10.2013
• Subjects: Animals; Lactic Acid - chemistry; Mice; Mice, Hairless; Microscopy, Electron, Scanning; Microscopy, Fluorescence; Nanoparticles; Photochemotherapy; Photosensitizing Agents - administration & dosage; Photosensitizing Agents - pharmacokinetics; Polyglycolic Acid - chemistry; Polylactic Acid-Polyglycolic Acid Copolymer; Protoporphyrins - administration & dosage; Protoporphyrins - pharmacokinetics; Skin - metabolism
• ISSN: 1533-4880
• DOI: 10.1166/jnn.2013.7789

Poly(D,L lactic-co-glycolic acid) (PLGA) based nanoparticles (NPs) are proposed for topical delivery of Protoporphyrin IX (PpIX) in Photodynamic Therapy of skin cancers. PpIX loaded into PLGA NPs showed nanometric average diameter (-280 nm), spherical forms and pH - 5.7, conditions suitable for topical application. In vitro release of PpIX from NPs was sustained up to 24 hr with a burst release effect of about 37.0% at 2 hr. Penetration and distribution of PpIX in hairless mice skin was determined by fluorescence microscopy 8 or 24 hrs after application of PpIX-NPs in the animals. At 24 hours, areas located in deeper regions of the skin were found to have greater fluorescence intensity. The finding indicates a localized effect of PpIX-NPs in the epidermis plus dermis--a site of action for topical PDT--and suggests a potential use of PpIX-NPs in PDT associated to skin cancer treatments.