Liquid crystalline dendrimer: Sythesis and Chracterization

A new family of nematic liquid crystal dendrimers derived from 3,5-dihydroxybenzoic acid were synthesized. The synthesis of the dendrimers compounds shows the influence of the dendritic core on the mesomorphic properties. The liquid crystalline properties were studied by polarizing optical microscopy (POM) equipped with a hot stage, the structures of the synthesized compounds characterized using FTIR and 1HNMR spectroscopy

Synthesis and Characterization of New Mesomorphic Azo Compounds and Study their Photoluminesecence Properties

The preparation of a new Azo compounds of highly conjugated dimeric and polymeric liquid crystal to achieve the crystalline characteristics Which have structures assigned based on elemental analysis, IR 1HNMR and CHNS-O while mesogenic properties have been set for DSC and hot-stage polarizing optical microscopy. The compounds show enantiotropicnematic phase being displayed. The compounds show photoluminescence properties in the organic solution at room temperature, with the fluorescence band centered around 400 nm

Synthesis, Characterization and Estimation the Biological Activity of New Mesomorphic Heterocyclic Compounds

Methicillin-resistant Staphylococcus aureus (MRSA) is a S. aureus that resistant to β-lactam antibiotics (e.g., Cefoxitin and Oxacillin). MRSA has a tremendous capacity to develop resistance to other classes of antibiotics and forming a real threat to patients. The process of exploring a new tactic of non-antibiotic treatments has become an urgent need. A bacteriophage is one of the possible treatments that strongly suggested. Bacteriophages are viruses that infect bacteria as a natural host with a bactericidal capability against multidrug-resistant bacteria that do not respond to conventional antibiotics. The current study investigates the lytic efficacy of phage-cocktail in vitro, specifically against S. aureus isolated from skin infections and find out the possible association of phage-antibiotic resistance. A total of 43 isolates of Methicillin-resistant staphylococcus aureus were isolated from skin infections. The isolates are distributed as (10 isolates of burn, 4 isolates of diabetic foot ulcer, 7 isolates of surgical wounds, 3 isolates of pressure ulcer, and 19 of skin and soft tissue infection). The isolates exhibited variant antibiotic susceptibility against 12 antibiotics (Cefoxitin FOX, Vancomycin VAN, Oxacillin OX, Rifampin RA, Chloramphenicol C, Nitrofurantoin F, Clindamycin DA, Azithromycin AZM, Amikacin AK, Trimethoprim-sulfamethoxazole SXT, Ciprofloxacin CIP, and Gentamicin CN). A bacteriophage cocktail was isolated using a phage-enrichment technique, high titer phage lysate (5*109 pfu/ml) was obtained and investigated against 43 MRSA isolates. The phage-cocktail showed high specificity to S. aureus but variable susceptibility to 43 MRSA isolates. It was observed that there was no association (p greater than 0.05) between phage and antibiotic resistance of (FOX, OX, VAN, RA, C, F, and DA) where the significant association was observed (p less than 0.05) with (AZM, AK, SXT, CIP, and CN). Significantly, the more antibiotic-resistant isolates exhibited more sensitivity to phage-cocktail, which represents a promising alternative to antibiotics that do not affect with increasing antibiotic resistance.</jats:p

Synthesis of Dendrimers Liquid Crystalline Materials based on 1,3,5-triphenylbenzene

In this study, new compounds of discotic liquid crystalline dendrimers are prepared which is derived from 1,3,5-triphenylbenzene. The synthesis of these compounds shows the effect of dendrimer unit on the mesogenic properties. The structures of prepared compounds characterized by using spectroscopic method e.g. FT-IR and 1HNMR. The liquid crystalline phases of prepared compounds was identified by using the hot-stage polarizing optical microscope (POM) and differential scanning calorimeter (DSC).</jats:p

Nematic Mesogen with 1,3,4-Oxadiazole Unit as Stationary Phase in Gas-Liquid Chromatography

This paper is the first that deals with the new synthesis of nematic liquid crystal titled bis-[5-yl-phenylbenzidine-4`-butyloxyphenly-2-yl-1,3,4-oxadiazole] and secondly discusses research on materials that can be used in stationary phase by using (GLC) as a type of chromatography. The usage of bis-[5-yl-phenylbenzidine-4`-butyloxyphenly-2-yl-1,3,4-oxadiazole]nematic phase has resulted in a lot of superb separations of a lot of poly aromatic hydrocarbons. The retention time change in an unusual way with temperature, appearance a significant increase at the normal liquid transmission point; as expected, that impact is reduced with further planar compounds. FT-IR and 1HNMR were used to characterize the synthesized chemical structure, and POM and DSC were used to investigate the liquid crystalline characteristics.</jats:p