Publications by authors named "Andre B da Fonseca Antunes"

Here we report on a simple, generally applicable method for depositing metal nanoparticles on a wide variety of solid surfaces under all aqueous conditions. Noble-metal nanoparticles obtained by citrate reduction followed by coating with thermoresponsive polymers spontaneously form a monolayer-like structure on a wide variety of substrates in presence of sodium chloride whereas this phenomenon does not occur in salt-free medium. Interestingly, this phenomenon occurs below the cloud point temperature of the polymers and we hypothesize that salt ion-induced screening of electrostatic charges on the nanoparticle surface entropically favors hydrophobic association between the polymer-coated nanoparticles and a hydrophobic substrate.

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Enteric diseases still have a devastating impact on global health. Oral vaccination is crucial to prevent intestinal infections, since only vaccines delivered to the intestinal tract elicit potent immune responses at the site of pathogen entry. However, oral vaccines encounter multiple barriers, including poor uptake and tolerance mechanisms, preventing the immune system to react to innocuous environmental antigens.

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Polymeric multilayer films assembled via hydrogen-bonding are witnessing increased interest from the scientific community. Here we report on hydrogen bonded multilayers of tannic acid and neutral poly(2-oxazoline)s. Importantly we demonstrate, to the best of our knowledge, for the first time that a temperature responsive polymer, in this case poly(2-(n-propyl)-2-oxazline), can be assembled below and above its TCP with distinctly different growth mechanisms.

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Poor water-solubility is becoming the leading hurdle for novel drug molecules to reach the market. Enhancing the surface-to-volume ratio by reducing the drug particles size has emerged as a powerful method to enhance the drug dissolution rate of poorly water-soluble drugs. Here we present several approaches to produce micro- and nano-suspensions of febantel and itraconazole, as poorly water-soluble model drugs, in the presence of the self-emulsifying excipient Gelucire 44/14 as additional solubility enhancing agent.

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Here, we aim to evaluate Gelucire 44/14 as non-ionic surface-active excipient to produce immediate-release solid dosage forms for poorly water-soluble drugs. Gelucires are polyethylene glycol (PEG) glycerides composed of mono-, di- and triglycerides and mono- and diesters of PEG. They are inert semi-solid waxy amphiphilic excipients with surface-active properties that spontaneously form a fine dispersion or emulsion upon contact with water.

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