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Fluorescent amphiphilic polymers were produced by grafting different types and levels of hydrophobic pendant groups with intrinsic fluorescent properties (fluorenylmethoxy carbonyl (Fmoc), dimethylamino-1-naphthalenesulfonyl (Dansyl), and naphthalene (Naphth) to a water soluble homopolymer backbone, polyallylamine (PAA). Non-fluorescent hydrophobic pendant group (cholesteryl moieties) were also grafted onto PAA. The polymers were characterized with elemental analysis, NMR and FTIR spectroscopy. All polymers formed self-assemblies by probe sonication in water with sizes ranging from 120 to 199 nm and TEM images showed the presence of spherical particles. The critical aggregation concentration (CAC) varied from 0.093 to 1.5 mg ml−1 depending on the type of hydrophobic pendant groups. The Cholesteryl and Dansyl polymers showed the presence of one CAC while the Fmoc and Naphth grafted polymers revealed the presence of two CACs. The first CAC observed was possibly due to intermolecular aggregation while the second CAC at the higher polymer concentration was the result of excimer formation revealed by their fluorescent spectra. We reasoned that Naphth and Fmoc aromatic pendant groups possess a flat stereochemistry, thus allowing π- π stacking at higher concentrations. The presence of the N-dimethylamino group in the Dansyl moiety gives rise to a 3D structure, thus hindering any stacking. The understanding of the supramolecular assemblies formed by these fluorescent amphiphilic polymers will aid in the engineering of advanced materials with superior functionality for biomedical applications. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The physicochemical compatibility between amphiphilic polymers and hydrophobic drugs has been recognized as an important issue for improving the drug solubilisation in polymeric micelle formulations. In this work, poly-L-lysine (PLL) grafted by cholate pendants as the only hydrophobic moiety were synthesized in order to facilitate the solubilisation of sterol drugs. Results showed that micelles formed by cholate grafted PLL encapsulated significantly higher level of prednisolone and estradiol than palmitoylated PLL micelles, whereas the solubilisation capacity of non-sterol drug (griseofulvin) is inefficient for both polymers. This suggests that higher drug-polymer incorporation can be achieved by the inclusion of hydrophobic moieties with similar architecture as the drugs, i.e. 'drug-like' functional groups, which will be useful for the future design of colloidal systems for the encapsulation of specific drug. [ABSTRACT FROM AUTHOR]

Nanoparticles have been shown to be effective drug carriers in cancer therapy. Pancreatic cancer forms dense tumours which are often resistant to drug molecules. In order to overcome such multidrug resistance, new drug entities, novel delivery systems and combination therapy strategies are being explored. In this paper, we report the design and synthesis of a poly(allylamine)-based amphiphile modified with hydrophobic naphthalimido pendant groups. Bisnaphthalimide compounds have been shown to possess anticancer activity. The potential of this polymer to encapsulate, solubilize and enhance drug (5-fluorouricil and bis-(naphthalimidopropyl)-diaminooctane) cytotoxicity in BxPC-3 cells was evaluated. Our studies showed that the insoluble drugs could be formulated up to 4.3 mg mL−1 and 2.4 mg mL−1 inside the amphiphiles, respectively. Additionally, the novel poly(allylamine)-naphthalimide carrier resulted in an amplification of cytotoxic effect with drug treatment after 24 h, and was capable of reduction of 50% cell population at concentrations as low as 3 μg mL−1. [ABSTRACT FROM AUTHOR]

Abstract: Bisnaphthalimidopropyl (BNIP) derivatives were recently identified as inhibitors of the Leishmania Silent Information Regulator 2 (SIR2) NAD+-dependent deacetylase. In this report we have for the first time, determined the potential of these compounds to treat visceral leishmaniasis using BALB/c mice chronically infected with Leishmania infantum as a model. These experiments led to the identification of BNIPdiaminooctane (BNIPDaoct) as an effective compound able to induce significant reduction of the parasite load in the spleen and in the liver. Indeed, at a dose of 1mg/kg, BNIPDaoct was more effective to treat leishmaniasis in a short course treatment (3 or 6 drug administrations) than the standard amphotericin B. Moreover, no indications of hematological toxicity were detected as evaluated by the hemoglobin, hematocrit, white and red blood cell counts, hence making BNIPDaoct a potential therapeutic agent against leishmaniasis. [Copyright &y& Elsevier]

For a number of years there has been intense interest in phytochemicals due to their potential health benefits. One readily available and rich source of phytochemicals is Rapeseed pomace (RSP), a waste product obtained after edible oil production from Brassica napus . In this work, we analysed the ubiquitous secondary metabolites in RSP (harvest 2014, North East of Scotland) after soxhhlet ethanol/water (95:5) extraction. LC-MS/MS data of the extract revealed several secondary metabolites, with sinapic acid being the most abundant. The presence of a high level of phenolics in the extract was confirmed with the folin ciocalteu assay. Strong antioxidant activities of the extract was determined by using common antioxidant assays (FRAP, DPPH and ORAC). In addition, the extract (13.9 μg/mL) provided complete pBR322 plasmid DNA protection, from oxidative stress induced by AAPH (3.5 mM). Interestingly, in vitro analysis showed that the RSP extract exhibited acetylcholinesterase inhibition activity in a time and concentration dependant manner. Furthermore, cellular studies showed that incubation of neuroblastoma cells (SH Sy-5Y) with RSP extract protected cell metabolism from reactive oxygen species produced by H 2 O 2 (1 mM). We are currently undertaking in vivo studies using the model organism C. elegans . Preliminary results showed that RSP extract is non-toxic (up to 5 mg/mL) and has neuroprotective properties in C. elegans models of neurodegenerative diseases (work in progress). The positive properties associated with the RSP extract in this study warrants further investigation for the revalorisation of rapeseed pomace in the health/food industry. [ABSTRACT FROM AUTHOR]