Vesicles as carriers for topical delivery of phycocyanin

Phycobiliproteins are water-soluble fluorescent proteins derived from cyanobacteria and eukaryotic algae. Phycocyanin (PC) is one of the main biliprotein of blue-green algae, such as Spirula (Arthospira) maxima. The antioxidant and antiinflammatory properties of PC were described by several authors. Our previous studies showed that conventional phospholipid vesicles were capable of improving anti-inflammatory activity of PC in mice, in a dose dependent fashion. Indeed, liposomes were able to give the same anti-inflammatory response than the free protein by using half PC dose.1 In the present work, PC was obtained from dry extract of Aphanizomenon Flos Aquae green blue algae (AFAMAX ®). PC extraction and purity was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE), MALDI top-down sequencing, and UV absorption. Purified PC was encapsulated in different phospholipid vesicles. In particular, Penetration Enhancer containing Vesicles (PEVs) were prepared using a commercial mixture of phospholipids (Phospholipon 50, P50) and 2-(2-Ethoxyethoxy) ethanol (Transcutol® P, Trc) or propylene glycol (PG). Conventional phospholipid liposomes and ethosomes were prepared with the same phospholipid mixture P50 and used as controls. All the vesicular dispersions were tested aiming at evaluating the influence of vesicle encapsulation on the PC ex vivo penetration into and permeation through human skin. PC vesicles were labelled with rhodamine and their penetration extent and localization in the skin strata were visualized by confocal laser scanning microscopy (CLSM).