Biomedical subjects

Lubica Macakova

Publications and source records attributed to Lubica Macakova.

3 recordsLinked to original sources

PubMed2007

Lack of association between a cationic protein and a cationic fluorosurfactant.

Surface tension, 19F and 1H NMR spectroscopy, and cryotransmission electron microscopy are used to characterize the state of association in aqueous solutions of a fluorosurfactant CF3(CF2)nSO2NH(CH2)3-4N(CH3)3+ I- (n = 8, 6) with and without lysozyme added. In the absence of lysozyme, we find monomers, small aggregates, and large vesicles to coexist, with the individual fluorosurfactant molecules exchanging slowly (>1 ms) among those states. When both lysozyme and fluorosurfactant are present in the solution, they have no measurable influence on the physical state of the other. In contrast, a hydrogenated cationic surfactant with the same headgroup, hexadecyltrimethylammonium bromide, is shown to associate to lysozyme.

Cations↗

PubMed2005

Mucin-chitosan complexes at the solid-liquid interface: multilayer formation and stability in surfactant solutions.

The adsorption of a biologically important glycoprotein, mucin, and mucin-chitosan complex layer formation on negatively charged surfaces, silica and mica, have been investigated employing ellipsometry, the interferometric surface apparatus, and atomic force microscopy techniques. Particular attention has been paid to the effect of an anionic surfactant sodium, dodecyl sulfate (SDS), with respect to the stability of the adsorption layers. It has been shown that mucin adsorbs on negatively charged surfaces to form highly hydrated layers. Such mucin layers readily associate with surfactants and are easily removed from the surfaces by rinsing with solutions of SDS at concentrations > or =0.2 cmc (1 cmc SDS in 30 mM NaCl is equal to 3.3 mM). The mucin adsorption layer is negatively charged, and we show how a positively charged polyelectrolyte, chitosan, associates with the preadsorbed mucin to form mucin-chitosan complexes that resist desorption by SDS even at SDS concentrations as high as 1 cmc. Thus, a method of mucin layer protection against removal by surfactants is offered. Further, we show how mucin-chitosan multilayers can be formed.

Binding Sites↗

PubMed2005

Dendritic structures based on bis(hydroxymethyl)propionic acid as platforms for surface reactions.

In this paper we present results related to the self-assembly of different generations of disulfide-cored 2,2-bis(hydroxymethyl)propionic acid-based dendritic structures onto gold surfaces. These molecular architectures, ranging from generation 1 to generation 3, contain removable acetonide protecting groups at their periphery that are accessible for hydrolysis with subsequent formation of OH-terminated surface-attached dendrons. The deprotection has been investigated in detail as a versatile approach to accomplish reactive surface platforms. A special focus has been devoted to the comparison of the properties of the layers formed by hydrolysis of the acetonide moieties directly on the surface and in solution, prior to the layer formation.

Journal Article↗