Modifying Membranotropic Action of Antimicrobial Peptide Gramicidin S by Star-like Polyacrylamide and Lipid Composition of Nanocontainers.

Gramicidin S (GS), one of the first discovered antimicrobial peptides, still shows strong antibiotic activity after decades of clinical use, with no evidence of resistance. The relatively high hemolytic activity and narrow therapeutic window of GS limit its use in topical applications. Encapsulation and targeted delivery may be the way to develop the internal administration of this drug.

Synthesis of methotrexate-betulonic acid hybrids and evaluation of their effect on artificial and Caco-2 cell membranes.

An efficient protocol for the synthesis of novel methotrexate-betulonic acid hybrids with a (tert-butoxycarbonylamino)-3,6-dioxa-8-octanamine (Boc-DOOA) linkage has been developed. Reaction of N-(2-(2-(2-aminoethoxy)ethoxy)ethyl)-betulonamide with methotrexate resulted in a mixture of isomeric conjugates which were separated by column chromatography. Their structures and composition have been fully established by H NMR, C spectra, FAB mass spectrometry and elemental analysis.

Thermoresponsive cholesteric liquid-crystal systems doped with terpenoids as drug delivery systems for skin applications.

Stimuli-responsive and tunable soft-matter systems are an advanced class of materials applicable for drug delivery. Liquid crystals (LCs) are promising candidates as multifunctional materials that can respond to temperature, light or magnetic field. Particularly, ordering and physical properties of thermoresponsive LCs depend predominantly on temperature as external trigger.

Investigation of thioctic acid, magnesium stearate and pyridoxine hydrochloride compatibility.

To identify possible interactions of components in dosage forms, studies are usually carried out at the stage of pharmaceutical development. Such studies can predict compatibility of active pharmaceutical ingredients and excipients in order to optimize drug formulation and certain parameters of technological process. Compatibility of some components of a newly developed neuroprotective medicinal product Neuronucleos, namely, thioctic acid, pyridoxine hydrochloride, magnesium stearate and magnesium lactate, was studied by means of differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR).

Biological properties of two enantiomorphic forms of N-(2,6-dimethylphenyl)-4-hydroxy-2,2-dioxo-1H-2λ,1-benzothiazine-3-carboxamide, a structural analogue of piroxicam.

The title benzothiazine-3-carboxamide, CHNOS, crystallized in two enantiomorphic crystal forms with the space groups P3 and P3 despite the absence of a classic stereogenic atom. The molecular structures are mirror images of each other. Only one sulfonyl O atom takes part in intramolecular hydrogen bonding as a proton acceptor and this atom is different in the two enantiomorphic structures.

Interaction of the anti-tuberculous drug bedaquiline with artificial membranes and rat erythrocytes.

Bedaquiline (BDQ) is a new drug from the family of diarylquinolines, which has a potent bactericidal activity against Mycobacterium tuberculosis. This paper has examined the interaction of BDQ with model membranes (liposomes and BLM) and rat erythrocytes. It was shown that BDQ (1-10 mol%) changed the thermotropic phase behavior of DMPC liposomes, leading to the lateral phase separation in the lipid bilayer and the formation of membrane microdomains.