Nile red nanosuspensions as investigative model to study the follicular targeting of drug nanocrystals.
The strategy of formulating poorly soluble actives as nanosuspension has been explored by more than a thousand research papers, with some medicinal products for oral and intravenous use having reached the market or advanced clinical trials. Interestingly, there is a limited number of reports of nanosuspensions formulated for dermal and transdermal drug delivery. In the present work, a nanocrystals suspension of the fluorescent, water-insoluble dye Nile Red, is prepared through a media milling technique and exploited to characterize the fate of the nanosuspended drug when applied on the skin. More in detail, the accumulation of Nile Red nanocrystals inside the hair follicles is evidenced by scanning electron microscopy, and the diffusion of drug molecules in the different skin layers is evaluated by confocal microscopy and skin permeation studies. Overall, the combination of the analytical techniques provide a description of the mechanisms underlying dermal accumulation, and transdermal penetration of a drug formulated as a nanosuspension.
Dept. Scienze della Vita e dell'Ambiente, Sezione di Scienze del Farmaco, CNBS, University of Cagliari, Cagliari 09124, Italy.
Francesco
F
Corrias
Dept. Scienze della Vita e dell'Ambiente, Sezione di Scienze del Farmaco, CNBS, University of Cagliari, Cagliari 09124, Italy.
Michele
M
Schlich
Dept. Scienze della Vita e dell'Ambiente, Sezione di Scienze del Farmaco, CNBS, University of Cagliari, Cagliari 09124, Italy.
Chiara
C
Sinico
Dept. Scienze della Vita e dell'Ambiente, Sezione di Scienze del Farmaco, CNBS, University of Cagliari, Cagliari 09124, Italy.
Rosa
R
Pireddu
Dept. Scienze della Vita e dell'Ambiente, Sezione di Scienze del Farmaco, CNBS, University of Cagliari, Cagliari 09124, Italy; Istituto di Scienze delle Produzioni Alimentari (ISPA)-CNR, sez. di Sassari, 07040 Baldinca, Italy.
Donatella
D
Valenti
Dept. Scienze della Vita e dell'Ambiente, Sezione di Scienze del Farmaco, CNBS, University of Cagliari, Cagliari 09124, Italy.
Anna Maria
AM
Fadda
Istituto di Scienze delle Produzioni Alimentari (ISPA)-CNR, sez. di Sassari, 07040 Baldinca, Italy.
Salvatore
S
Marceddu
Dept. Scienze della Vita e dell'Ambiente, Sezione di Scienze del Farmaco, CNBS, University of Cagliari, Cagliari 09124, Italy. Electronic address: frlai@unica.it.
Francesco
F
Lai
D000279:Administration, Cutaneous; D000818:Animals; D004339:Drug Compounding; D016503:Drug Delivery Systems; D066298:In Vitro Techniques; D053758:Nanoparticles / Q000737:chemistry*; D010078:Oxazines / Q000032:analysis*; D012867:Skin / Q000187:drug effects; D012869:Skin Absorption; D013552:Swine
D010078:Oxazines; C044808:nile red
Dermal delivery; Follicular targeting; Nanocrystals; Nanosuspensions; Nile red