Extraction, Purification and Nanoformulation of Natural Phycocyanin (from <I>Klamath</I> <I>algae</I>) for Dermal and Deeper Soft Tissue Delivery

This study focuses on the extraction and isolation of a natural anti-inflammatory phycocyanin and its nanoformulation in innovative and efficient vesicular carriers able to improve its delivery to the skin. C-phycocyanin was successfully isolated from a commercial dry extract (AfaMax) of blue-green Klamath algae. Protein extraction and purity were confirmed by gel electrophoresis (SDS PAGE), MALDI top-down sequencing, Liquid Chromatography/Mass Spectrometry, and UV absorption. Purified C-phycocyanin was then encapsulated in different phospholipid vesicles: liposomes, ethosomes and Penetration Enhancer containing Vesicles (PEVs), the latter containing the penetration enhancer propylene glycol or Transcutol P. The main colloidal characteristics of the systems were assessed, showing spherical vesicles around 100 nm, negatively charged, with different lamellarity depending on the formulation composition. An in depth investigation on vesicle geometrical properties and morphology was carried out by Small and Wide-Angle X-ray Scattering. Further, the ability of rhodamine-labelled vesicles to allow fluorescent phycocyanin penetration and distribution through human skin was evaluated by Confocal Laser Scanning Microscopy, while a complete picture of vesicle-treated skin architecture was gained using Scanning Electron Microscopy. Results indicate that PEVs, especially propylene glycol containing vesicles, are promising carriers for the delivery of the high molecular weight protein phycocyanin to the deep skin layers.