Paclitaxel Magnetic Core⁻Shell Nanoparticles Based on Poly(lactic acid) Semitelechelic Novel Block Copolymers for Combined Hyperthermia and Chemotherapy Treatment of Cancer.

Magnetic hybrid inorganic/organic nanocarriers are promising alternatives for targeted cancer treatment. The present study evaluates the preparation of manganese ferrite magnetic nanoparticles (MnFe2O4 MNPs) encapsulated within Paclitaxel (PTX) loaded thioether-containing ω-hydroxyacid-co-poly(d,l-lactic acid) (TEHA-co-PDLLA) polymeric nanoparticles, for the combined hyperthermia and chemotherapy treatment of cancer. Initially, TEHA-co-PDLLA semitelechelic block copolymers were synthesized and characterized by 1H-NMR, FTIR, DSC, and XRD. FTIR analysis showed the formation of an ester bond between the two compounds, while DSC and XRD analysis showed that the prepared copolymers were amorphous. MnFe2O4 MNPs of relatively small crystallite size (12 nm) and moderate saturation magnetization (64 emu·g-1) were solvothermally synthesized in the sole presence of octadecylamine (ODA). PTX was amorphously dispersed within the polymeric matrix using emulsification/solvent evaporation method. Scanning electron microscopy along with energy-dispersive X-ray spectroscopy and transmission electron microscopy showed that the MnFe2O4 nanoparticles were effectively encapsulated within the drug-loaded polymeric nanoparticles. Dynamic light scattering measurements showed that the prepared nanoparticles had an average particle size of less than 160 nm with satisfactory yield and encapsulation efficiency. Diphasic PTX in vitro release over 18 days was observed while PTX dissolution rate was mainly controlled by the TEHA content. Finally, hyperthermia measurements and cytotoxicity studies were performed to evaluate the magnetic response, as well as the anticancer activity and the biocompatibility of the prepared nanocarriers

Biocomposite films based on κ-carrageenan/locust bean gum blends and clays : physical and antimicrobial properties

The aims of this work were to evaluate the physical and antimicrobial properties of biodegradable films composed of mixtures of κ-carrageenan (κ-car) and locust bean gum (LBG) when organically modified clay Cloisite 30B (C30B) was dispersed in the biopolymer matrix. Film-forming solutions were prepared by adding C30B (ranging from 0 to 16 wt.%) into the κ-car/LBG solution (40/60 wt.%) with 0.3 % (w/v) of glycerol. Barrier properties (water vapour permeability, P vapour; CO2 and O2 permeabilities), mechanical properties (tensile strength, TS, and elongation-at-break, EB) and thermal stability of the resulting films were determined and related with the incorporation of C30B. Also, X-ray diffraction (XRD) was done in order to investigate the effect of C30B in film structure. Antimicrobial effects of these films against Listeria monocytogenes, Escherichia coli and Salmonella enterica were also evaluated. The increase of clay concentration causes a decrease of P vapour (from 5.34 × 10−11 to 3.19 × 10−11 g (m s Pa)−1) and an increase of the CO2 permeability (from 2.26 × 10−14 to 2.91 × 10−14 g (m s Pa)−1) and did not changed significantly the O2 permeability for films with 0 and 16 wt.% C30B, respectively. Films with 16 wt.% clay exhibited the highest values of TS (33.82 MPa) and EB (29.82 %). XRD patterns of the films indicated that a degree of exfoliation is attained depending on clay concentration. κ-car/LBG–C30B films exhibited an inhibitory effect only against L. monocytogenes. κ-car/LBG–C30B composite films are a promising alternative to synthetic films in order to improve the shelf life and safety of food products.J. T. Martins, A. I. Bourbon, A. C. Pinheiro and M. A. Cerqueira gratefully acknowledge the Fundacao para a Ciencia e Tecnologia (FCT, Portugal) for their fellowships (SFRH/BD/32566/2006, SFRH/BD/73178/2010, SFRH/BD/48120/2008 and SFRH/BPD/72753/2010, respectively), and B. W. S. Souza acknowledges the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES, Brazil)

The impact of technological innovation on building a sustainable city

By 2050, the population living in major cities, especially in developing countries, will have increased twofold. With the increasing majority of the population occurring in urban areas, it is crucial to focus on how technological innovation can help to deliver a sustainable future. A sustainable city strives to create a sustainable living environment through the use of technology. Thus, the main objective of this paper is to review the impact of technological innovation on building a more sustainable city. Technological innovation has changed the overall effectiveness and benevolence over time and with regard to sustainability. A sustainable city involves development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Sustainable development encompasses all aspects of environmental stewardship, social development, and economic progress

Biocompatible Zr-based nanoscale MOFs coated with modified poly (ε-caprolactone) as anticancer drug carriers

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