Inscriere cercetatori

Premii Ad Astra

premii Ad Astra

Asociația Ad Astra a anunțat câștigătorii Premiilor Ad Astra 2022: http://premii.ad-astra.ro/. Proiectul și-a propus identificarea și popularizarea modelelor de succes, a rezultatelor excepționale ale cercetătorilor români din țară și din afara ei.

Asociatia Ad Astra a cercetatorilor romani lanseaza BAZA DE DATE A CERCETATORILOR ROMANI DIN DIASPORA. Scopul acestei baze de date este aceea de a stimula colaborarea dintre cercetatorii romani de peste hotare dar si cu cercetatorii din Romania. Cercetatorii care doresc sa fie nominalizati in aceasta baza de date sunt rugati sa trimita un email la cristian.presura@gmail.com

Incorporation of Single-Wall Carbon Nanotubes into an Organic Polymer Monolithic Stationary Phase for -HPLC and Capillary Electrochromatography

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: Yan Li, Yuan Chen, Rong Xiang, Dragos Ciuparu, Lisa D. Pfefferle, Csaba Horvath, and James A. Wilkins

Editorial: Analytical Chemistry, 77(5), p.1398-1406, 2005.

Rezumat:

Single-wall carbon nanotubes (SWNT) were incorporated into an organic polymer monolith containing vinylbenzyl chloride (VBC) and ethylene dimethacrylate (EDMA) to form a novel monolithic stationary phase for high-performance liquid chromatography (HPLC) and capillary electrochromatography (CEC). The retention behavior of neutral compounds on this poly(VBC-EDMA-SWNT) monolith was examined by separating a mixture of small organic molecules using micro-HPLC. The result indicated that incorporation of SWNT enhanced chromatographic retention of small neutral molecules in reversed-phase HPLC presumably because of their strongly hydrophobic characteristics. The stationary phase was formed inside a fused-silica capillary whose lumen was coated with covalently bound polyethyleneimine (PEI). The annular electroosmotic flow (EOF) generated by the PEI coating allowed peptide separation by CEC in the counterdirectional mode. Comparison of peptide separations on poly(VBC-EDMA-SWNT) and on poly(VBC-EDMA) with annular EOF generation revealed that the incorporation of SWNT into the monolithic stationary phase improved peak efficiency and influenced chromatographic retention. The structures of pretreated SWNT and poly(VBC-EDMA-SWNT) monolith were examined by high-resolution transmission electron microscopy, Raman spectroscopy, scanning electron microscopy, and multipoint BET nitrogen adsorption/desorption.

Cuvinte cheie: PERFORMANCE LIQUID-CHROMATOGRAPHY, PEPTIDES, SEPARATION, PROTEINS, CO-MCM-41, COLUMNS, PURIFICATION

URL: http://pubs3.acs.org/acs/journals/doilookup?in_doi=10.1021/ac048299h