A number of oxotitanium(IV) complexes of the type TiOL with bisunsymmetric dibasic tetradentate Schiff base (LH 2 ) containing ONNO donor atoms have been synthesized. Mono-Schiff base (OPD-HNP) was prepared by the condensation of 1:3 molar ratio of 2-hydroxy-1-naphthaldehyde (HNP)with o-phenylenediamine (OPD). Dibasic unsymmetric tetradentate diamine Schiff bases were prepared by the reaction of OPD-HNP with 2-hydroxyacetophenone, 2-hydroxypropeophenone, benzoylacetone, acetylacetone and ethylacetoacetate. Further, titanylacetylacetonate was reacted with these ligands to obtain their metal complexes. On the basis of analytical and physiochemical data, the formation of complexes as TiOL was suggested having square pyramidal geometry. Quantum mechanical approach also confirmed this geometry. The assessment of the synthesized ligands and their complexes showed that some behave as good inhibitors of mycelial growth against selected phytopathogic fungi but weak inhibitors against some selected bacteria. A few of them also showed antioxidant properties.

No abstract

Streptococcus mutans is the primary etiological agent responsible for dental caries. Microfluidic devices have been used to provide a level of control over bacterial microenvironments under laminar flow conditions. In this study, we used a microfluidic device packed with glass beads to simulate the interproximal space, which is the space between the teeth. In the device, the effects of environmental factors, such as sucrose and metal ions, on S. mutans attachment and biofilm formation were quantitatively measured using confocal laser scanning microscopy and atomic force microscopy. We determined that sucrose was required for both bacterial attachment and exopolysaccharide (EPS) production in S. mutans. These results suggest that the in vivo condition between the teeth was successfully mimicked and that the device is highly suitable for in situ monitoring of oral biofilms.

No abstract

No abstract