Preparation of Liquid-Core Nanocapsules from Poly[(ethylene oxide)-co-glycidol] with Multiple Hydrophobic Linoleates at an Oil−Water Interface and Its Encapsulation of Pyrene

Strategies for the design of orally bioavailable antileishmanial treatments

Leishmaniasis is one of the six major tropical diseases targeted by the World Health Organization. The most serious, life-threatening form is visceral leishmaniasis (VL). No vaccine is yet available for human use and chemotherapy is the main mean of dealing with this disease. This review focuses on the development of drug delivery systems (DDS) for treatment of leishmaniasis. After an overview of the significance of leishmaniasis in 2013, current chemotherapy and its limitations are considered, leading to possible strategies to improve the treatment of VL: new drugs, combinations of existing drugs and DDS, particularly for oral administration. Nanostructured biomaterials such as lipid-based or polymeric nanoparticles have unique physicochemical properties, ultra-small and controllable size, large surface area to mass ratio and the possibility of surface modification which can be used to advantage for the oral administration of antileishmanial drugs. They can improve the rate of dissolution of poorly water-soluble drugs, increase intestinal residence time by bioadhesion and, especially when lipid additives are used, influence the route and efficiency of absorption. These recent advances in this very active field should lead to better management of this serious disease.

Preparation of the Amphiphilic Copolymer of Poly(ethyleneoxid-co-glycidol)-Graft-Poly(lactide) and their Extraction for Dyes

A well-defined graft copolymer poly(ethylene oxide-co-glycidol)-graft-Poly(lactide) [poly(EO-co-Gly)-g-PLA] of poly(ethylene oxide-co-glycidol) [(poly(EO-co-Gly)] as main chain and poly(lactide) (PLA) as the side chain was successfully prepared via combination of anionic polymerization and ring-opening polymerization. The glycidol was protected by ethyl vinyl ether first to form 2, 3-epoxypropyl-1-ethoxyethyl ether (EPEE), and then copolymerized with EO by initiation with the mixture of diphenylmethylpotassium and triethylene glycol to obtain the well-defined poly(EO-co-EPEE). The latter was hydrolyzed in the acidic conditions and then coordination-insertion ring-opening polymerization of lactide(LA) with poly(EO-co-Gly) was completed. The object products and intermediates were characterized by 1HNMR, MALDI-TOF-MS and GPC in detail. The experimental results confirmed that poly(EO-co-Gly)-g-PLA showed strong conjugation ability with the dyes.

Aqueous-core lipid nanocapsules for encapsulating fragile hydrophilic and/or lipophilic molecules

This paper presents the original method of producing aqueous-core lipid nanocapsule, able to encapsulate both hydrophilic and lipophilic species with relevant yields. The scope offered by the integration of both hydrophilic and lipophilic molecules within the same colloidal objects make this method a prime candidate for the numerous anticancer therapies for which chemotherapy frequently requires the association of several molecules. The proof of concept study is proposed here (i) describing in detail the formulation of such objects and their characterization (TEM, cryo-TEM, soft particle analysis), (ii) showing the encapsulation of hydrophilic species alone, using examples of very different molecular weights, such as a dye (methylene blue) and a protein (BSA-isothycianate fluorecein labeled), and (iii) showing the simultaneous encapsulation of hydrophilic (methylene blue) and lipophilic (also a dye, red Sudan III) species.

A study of internal rotations and vibrational spectra of oxiranemethanol (glycidol)

The conformational stability and the C-O and O-H internal rotations in oxiranemethanol were investigated at the DFT-B3LYP/6-311 G**, MP2/6-311 G** and MP4(SDQ)/6-311 G** levels of theory. Three minima were predicted in the CCOH potential energy scans of the molecule to have relative energies of about 2 kcal/mol or less and all were calculated to have real frequencies upon full optimization of structural parameters at the DFT and the MP2 levels of calculations. The Cg1 (H bond inner) conformation was predicted to be the lowest energy conformation for oxiranemethanol in excellent agreement with an earlier microwave study. The equilibrium mixture was calculated from Gibb's free-energy changes to be about 79% Cg1, 17% G1g and 3% Gg1 at the B3LYP/6-311G** level and about 87% Cg1, 11% G1g and 2% Gg1 at the MP2/6-311 G** level for oxiranemethanol at 298.15 K. No conclusive evidence was obtained for the presence of high-energy form in the liquid phase of oxiranemethanol. The vibrational frequencies of oxiranemethanol in its three stable forms were computed at the B3LYP level and complete vibrational assignments were made for the lowest energy Cg1 form on basis of calculated and experimental data of the molecule.