Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal. Electronic address:
Published: October 2016
AI Article Synopsis
Article Abstract
The interaction of DNA with 5,10,15,20-tetrakis(4-N-methylpyridiniumyl)porphyrin (TMPyP) in polyelectrolyte core-shells obtained via layer by layer adsorption of poly(sodium 4-styrenesulfonate), PSS, and poly(allylamine hydrochloride), PAH, polyelectrolytes was followed by steady state, time resolved fluorescence and by Fluorescence Lifetime Imaging Microscopy (FLIM). Our results show that DNA adsorption onto polyelectrolyte core-shell changes the TMPyP interaction within PSS/PAH core-shells structure and increase significantly the TMPyP uptake. Specific DNA/TMPyP interactions are also altered by DNA adsorption favouring porphyrin intercalation onto GC pair rich regions. Circular dichroism (CD) spectra reveal that DNA undergoes important conformational changes upon adsorption onto the core-shell surface, which are reverted upon TMPyP encapsulation.
The interaction of DNA with 5,10,15,20-tetrakis(4-N-methylpyridiniumyl)porphyrin (TMPyP) in polyelectrolyte core-shells obtained via layer by layer adsorption of poly(sodium 4-styrenesulfonate), PSS, and poly(allylamine hydrochloride), PAH, polyelectrolytes was followed by steady state, time resolved fluorescence and by Fluorescence Lifetime Imaging Microscopy (FLIM). Our results show that DNA adsorption onto polyelectrolyte core-shell changes the TMPyP interaction within PSS/PAH core-shells structure and increase significantly the TMPyP uptake. Specific DNA/TMPyP interactions are also altered by DNA adsorption favouring porphyrin intercalation onto GC pair rich regions.
Mesocrystals are of great importance owing to their novel hierarchical microstructures and potential applications. In the present work, a simple additive-free method has been developed for the controllable synthesis of manganese monoxide (MnO) mesocrystals, in which cheap manganese acetate (Mn(Ac)2) and ethanol were used as raw materials without involving any other expensive additives such as surfactants, polyelectrolyte, or polymers. The particle size of the resulting MnO mesocrystals is tunable in the range 400-1500 nm by simply altering the concentration of Mn(Ac)2 in ethanol.
