Altering Ion Transport Across Alumina Nanotube Membranes
Date of Graduation
Master of Science in Chemistry
nanochannels, ion transport, spectroscopy, alumina, silane
This research project examines the transport of ions through porous alumina membranes with channels of ̃200 nanometers in diameter. The test molecule is the permeate anion 1,5-naphthalene disulfonate (NDS2-), which as absorbance in the ultraviolet range and also exhibits fluorescence. This allows direct examination of transport by utilizing ultraviolet-visible spectroscopy as well as fluorescence spectroscopy. Adding substituents through strong alumina-silane linkages further modifies all the surfaces of the alumina nanotube membranes. Membranes are soaked in solutions containing either octadecyl trimethoxysilane (ODTMS) or isobutyl trimethoxysilane (IBTMS). Ion transport across the membrane treated with the hydrophobic octadecyl trimethoxysilane was hindered significantly, while the membranes exposed to a short alkyl chain isobutyl trimethoxysilane demonstrated only a slight blockage of ion transport. In both cases, addition of an ionic surfactant dodecyl benzenesulfonate (DBS) and also cationic drug bupivacaine reversed the trends, allowing increased transport of the permeant anion.
© Sai Sumana Penumetcha
Penumetcha, Sai Sumana, "Altering Ion Transport Across Alumina Nanotube Membranes" (2005). MSU Graduate Theses. 1875.