Avtor/Urednik		Sepčić, Kristina; Muševič, Igor; Lahajnar, Gojmir; Turk, Tom; Maček, Peter
Naslov		AFM imaging of surface adsorbed polymeric 3-alkylpyridinium salts from the marine sponge Reneira sarai
Tip		članek
Vir		Int J Biol Macromol
Vol. in št.		Letnik 26
Leto izdaje		1999
Obseg		str. 353-6
Jezik		eng
Abstrakt		Bioactive 3-alkylpyridium polymers (Poly-APS) have recently been isolated from the marine sponge Reniera sarai. Previous results have shown that these molecules in aqueous solutions form suprammolecular aggregates with an average hydrodynamic radius of 23+- 2 nm. To obtain additional evidences about the shape and the dimensions of poly-APS aggregates, we used atomic force microscopy (AFM) operating in tapping mode. The images clearly showed adsorbed aggregates with a lateral dimension of aprox. 40 nm and a thickness of the order of aprox. 1 nm. The distribution of volumes of the adsorbed aggregates is very similar to the distribution of hydrodynamic radii as obrained from the dynamic light scattering experiments. The volume distribution of these aggregates shows a maximum at 1750 nm3, which corresponds to a sphere with a radius of 7.5 nm.
Deskriptorji		PORIFERA PYRIDINIUM COMPOUNDS MICROSCOPY, ATOMIC FORCE