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Irbesartan (IRB) exerts beneficial effects either alone or in combination with other drugs on numerous diseases, such as cancer, diabetes, and hypertension. However, due to its high lipophilicity, IRB does not possess the optimum pharmacological efficiency. To circumvent this problem, a drug delivery system with 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) was explored. The 1:1 complex between IRB and 2-HP-β-CD was identified through ESI QTF HRMS. Dissolution studies showed a higher dissolution rate of the lyophilized IRB-2-HP-β-CD complex than the tablet containing IRB at pH = 1.2. DSC results revealed the differences of the thermal properties between the complex and various mixtures consisting of the two components, namely IRB and 2-HP-β-CD. Interestingly, depending on the way the mixture preparation was conducted, different association between the two components was observed. Molecular dynamics (MD) simulations predicted the favorable formation of the above complex and identified the dominant interactions between IRB and 2-HP-β-CD. In vitro pharmacological results verified that the inclusion complex not only preserves the binding affinity of IRB for AT1R receptor, but also it slightly increases it. As the complex formulation lacks the problems of the tablet, our approach is a promising new way to improve the efficiency of IRB.

Gradient (or pseudo-diblock) copolymers were synthesized from 2-methyl-2-oxazoline and 2-phenyl-2-oxazoline monomer mixtures via cationic polymerization. The self-assembling properties of these biocompatible gradient copolymers in aqueous solutions were investigated, in an effort to use the produced nanostructures as nanocarriers for hydrophobic pharmaceutical molecules. Dynamic and static light scattering as well as AFM measurements showed that the copolymers assemble in different supramolecular nanostructures (spherical micelles, vesicles and aggregates) depending on copolymer composition. Fluorescence spectroscopy studies revealed a microenvironment of unusually high polarity inside the nanostructures. This observation is related partly to the gradient structure of the copolymers. The polymeric nanostructures were stable with time. Their structural properties in different aqueous media—PBS buffer, RPMI solution—simulating conditions used in pharmacological/medicinal studies, have been also investigated and a composition dependent behavior was observed. Finally, the hydrophobic drug indomethacin was successfully encapsulated within the gradient copolymer nanostructures and the properties of the mixed aggregates were studied in respect to the initial copolymer assemblies. The produced aggregates encapsulating indomethacin showed a significant increase of their mass and size compared to original purely polymeric ones. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Liposomes were prepared from the isolated phospholipids of mature broad bean [Vicia faba L. (syn. Fabae calabaricae)] oil and their physical properties were studied. The method of preparation was the hydration of the thin lipid film, while the probe sonication methodology was used for reducing the size of the vesicles. The seeds of the broad bean were collected in two different periods of maturity and extracted by the Bligh-Dyer method, and the lipid classes were studied by HPTLC/FID. The oils were found to be rich in polar lipids (63.1% and 60.2% of total lipids) and low in neutral lipids (36.9% and 39.8% of total lipids) for the immature and mature seed oils, respectively. The neutral lipid fraction consisted mainly of triacylglycerides (34.2% and 32.3%) whereas the polar lipids mainly consisted of phospholipids (60.2% and 54.2%) for the mature and immature seed oils, respectively. Sphingolipids (8.9%) were identified only in the immature seed oil. The overall goal of this study was the preparation of a new liposomal formulation with physicochemical properties such as unique lipid composition, size and ζ-potential, which are important factors influencing drug delivery to the target tissues.

The structure of a novel CC clerodane type diterpenoid, namely (+)-19-acetoxy- cis -clerodan-3-ene-15-oic acid 1 was elucidated and its conformational properties were explored using a combination of high field NMR spectroscopy and computational analysis. The structural analysis provided results consistent with those obtained by a single X-ray diffraction study of its dicyclohexylammonium salt. The new clerodane type diterpene isolated in large quantities from Cistus monspeliensis L. leaves was found to exhibit significant antibacterial activity against Staphyloccoci (MIC 50 =0.085 mM) and therefore represents a promising lead compound. Interestingly the deacetylated derivative 2 of compound 1 was inactive.

pp. 107–123 This work was partially presented at the 7th Joint Meeting of AFRP, ASP, GA, PSE and SIF, Athens, Greece, and at the XIIIth COSMODERM Joint Meeting of ESCAD and the Hellenic Society of Dermatology and Venerology, Athens, Greece. In recent years, there is a considerable interest in the development of preservative-free or self-preserving cosmetics. The aim of our work was to develop new cosmetic formulations by replacing chemical preservatives with ingredients with antimicrobial properties that are not legislated as preservatives according to Annex VI of Commission Directive 76/768/EEC. This paper describes the preservative efficacy of the well-known antimicrobial extracts of Lonicera caprifoleum and Lonicera japonica in combination with glyceryl caprylate and/or levulinic acid, p-anisic acid, and ethanol. We prepared a series of acidic (pH = 5.5) aqueous and O/W formulations, i.e., tonic lotion, shampoo, shower gel, conditioning cream, anticellulite cream, cleansing milk and peeling cream, containing (0.2% w/w) Lonicera extracts, alone in the case of tonic lotion and in combination with (1% w/w) glyceryl caprylate in the other products, and we performed challenge tests according to the European Pharmacopoeia procedures and criteria. Formulations such as shampoo, shower gel, and conditioning cream fulfilled criterion A, while tonic lotion, anticellulite cream, cleansing milk, and peeling cream fulfilled criterion B, in regard to contamination from A. niger. Furthermore, we evaluated the efficacy of the antimicrobial systems in two states of use: the intact product and after 3 weeks of consumer use. The results showed that A. niger was also detected during use by consumers in the products that satisfied only criterion B in challenge tests. The addition of antimicrobial fragrance ingredients such (≤0.3% w/w) levulinic acid or (0.1% w/w) p-anisic acid and/or (5% w/w) ethanol afforded products that met criterion A in challenge tests and were also microbiologically safe during use. The small quantity (5% w/w) of ethanol gave an important assistance in order to boost the self-preserving system and to produce stable and safe products.