Inscriere cercetatori

Premii Ad Astra

premii Ad Astra

Asociația Ad Astra anunță lansarea proiectului Premiilor Ad Astra 2022 (link aici), care își propune identificarea și popularizarea modelelor de succes, a rezultatelor excepționale ale cercetătorilor români din țară și din afara ei. Regulamentul de participare se poate gasi aici, iar  pagina de inscriere se poate accesa aici.

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

A new alternative to amino acids transport: facilitated transport of Image-phenylalanine by hybrid siloxane membranes containing a fixed site macrocyclic complexant

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

Autori: M. Barboiu, C. Guizard, C. Luca, B. Albu, N. Hovnanian and J. Palmeri

Editorial: Elsevier, Journal of Membrane Science, 161, p.193-206, 1999.

Rezumat:

New heteropolysiloxane (HPS) membranes containing macrocyclic or linear complexants, chemically linked in a reticulated silica matrix, were synthetized by the sol–gel process and used for the facilitated transport of Image-phenylalanine. The solution–diffusion model was used to analyse experimental transport results obtained by studying the influence of the macrocyclic complexant, the pH value of the feed and the strip phases, the conditioning of the membrane, and the presence of K+ ions. This study has shed light on the role of the polytopic macrocyclic complexant. This complexant improved the partition of the amino acid into the membrane by specific macrocyclic complexation combined with non-covalent interactions (hydrogen bonding, charge interaction), leading to a dual mode transport mechanism. The transport of Image-Phenylalanine increased with the pH gradient between the feed and the strip phase; this transport simulated biological amino acid transport in cell membranes.

Cuvinte cheie: facilitate transport, membranes