Pseudohalogenation of methyl 9-hydroxy-cis-12-and 12-hydroxy-cis-9-octadecenoate

Pseudohalogenation of methyl 9-hydroxy-cis-12-octadecenoate (I) and methyl 12-hydroxy-cis-9-octadecenoate (II) has been carried out with N,N-dibromobenzenesulfonamide (NNDBS). Compounds I and II, on reaction with NNDBS, formed four and three products, respectively. The interesting feature of these reactions was the formation of 1,4-epoxy compounds. The structures of individual compounds were established with the help of elemental and spectral analysis.     

Targeting microbial biofilms: by Arctium lappa l. synthesised biocompatible CeO2 ‐NPs encapsulated in nano‐chitosan

This study is planned to synthesise new biocompatible, nano antimicrobial formulation against biofilm producing strains. Aqueous root extract of Arctium lappa l. was used to synthesise ceria nanoparticles (CeO₂ ‐NPs). The synthesised nanoparticles were encapsulated with nano‐chitosan by sol–gel method and characterised using standard techniques. Gas chromatography‐mass spectrometer of Arctium lappa l. revealed the presence of ethanol, acetone, 1‐ propanol, 2‐methylethane, 1,1‐di‐ethoxy, 1‐Butanol, and oleic acid acted as reducing and surface stabilising agents for tailoring morphology of CeO₂ ‐NPs. Erythrocyte integrity after treatment with synthesised nanomaterials was evaluated by spectrophotometer measurement of haemoglobin release having biocompatibility. Scanning electron microscopy revealed the formation of mono dispersed beads shaped particles with mean particle size of 26.2 nm. X‐ray diffractometry revealed cubic crystalline structure having size of 28.0 nm. After encapsulation by nano‐chitosan, the size of CeO₂ ‐NPs enhances to 48.8 nm making average coverage of about 22.6 nm. The synthesised nanomaterials were found effective to disrupt biofilm of S. aureus and P. aeruginosa. Interestingly, encapsulated CeO₂ ‐NPs revealed powerful antibacterial and biofilm disruption activity examined by fluorescent live/dead staining using confocal laser scanning microscopy. The superior antibacterial activities exposed by encapsulated CeO₂ ‐NPs lead to the conclusion that they could be useful for controlling biofilm producing multidrug resistance pathogens.Inspec keywords: particle size, microorganisms, organic compounds, nanomedicine, sol‐gel processing, cellular biophysics, scanning electron microscopy, optical microscopy, nanoparticles, antibacterial activity, fluorescence, biomedical materials, nanofabrication, X‐ray diffraction, chromatography, filled polymers, cerium compoundsOther keywords: microbial biofilms, aqueous root extract, sol–gel method, gas chromatography‐mass spectrometer, 1‐di‐ethoxy, 1‐Butanol, nanomaterial synthesis, mean particle size, antibacterial activities, ethanol, acetone, 1‐ propanol, biocompatible ceria‐nanoparticle encapsulation, nano‐chitosan, Arctium lappa l., oleic acid, erythrocyte integrity, spectrophotometer measurement, haemoglobin release, mono dispersed beads shaped particle formation, X‐ray diffractometry, cubic crystalline structure, fluorescent live/dead staining, confocal laser scanning microscopy, multidrug resistance pathogens, size 26.2 nm, size 28.0 nm, size 48.8 nm, size 22.6 nm, CeO₂      

Studies on a newly developed linseed oil‐based alumina‐filled polyesteramide anticorrosive coating

Polyesteramide (PEA) and alumina‐filled polyesteramide (APEA) resins were synthesized from N,N′‐bis(2 hydroxyethyl) linseed amide. The FTIR, ¹H‐NMR, DSC, TGA, thermal curing, and physico‐chemical characterization of these polymers were carried out. The coatings of PEA and APEA were made on mild steel strips. The mechanical behavior and protective efficiency of these coatings in acid, alkali, and organic solvents were investigated. APEA coatings have been found to show superior performance in comparison to other coatings. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1679–1687, 1999