Not PAMAM Dendrimer Nanodispersions and Pectine Microdispersion: two biocompatible approaches to increase Ellagic Acid water solubility and allow its more ways therapeutic administration

Ellagic acid (EA) 1 (Figure 1), a polyphenol present in some fruits, nuts and seeds has antioxidant and other several healthy properties. EA daily dietary intake is irrelevant for therapeutic purposes, but the administration of its effective doses could be a solution. This idea is hardly realizable due to EA water insolubility and low oral bioavailability. Toxic excipients and harmful solubilizing agents were extensively used for the obtainment of administrable drug formulations and for realizing the delivery of not water soluble drugs with unpleasant side effects. Nanoparticles represent a better alternative and even if highly cytotoxic, polycationic PAMAM dendrimers were among the most investigated materials. Today, neutral dendrimer scaffolds decorated with biocompatible protonable amino acids are preferred. Then, EA was incorporated inside not charged amino acid-modified hydrophilic (2)1 and amphiphilic (3)2 dendrimers by a synthetic procedure (Figure 1).Two nanosized (150-160 nm) EA formulations (DPXs) were obtained. Thanks to their surprisingly increased water solubility (300-1000 times), 46-53% DL, good antioxidant activity, very good buffer capacity, DPXs could be suitable for safe and effective parenteral administration of EA. Another total natural EA formulation was than prepared by EA entrapment in a tasteless food compatible pectin matrix. A solid microdispersion (EAMS, 10-20 µm, Figure 2) was obtained by spray drying technique and the commonly used organic co-solvent PEG-400 was avoided. EAMS shown 22% DL, 30 times improved water solubility and very good antioxidant power. As a research in progress has already proved, food compatible EAMS are suitable for oral administration of EA therapeutic doses and as additive in EA enriched functional foods preparation. References: [1] S. Alfei, S. Catena, 2018, submitted to Polym. Advan. Technol. 2018: https://doi.org/10.1002/pat.4396. [2] S. Alfei, S. Catena, 2018, submitted to Polym. Int. 2018, https://doi.org: 10.1002/pi.5680.