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Late diagnosis and systemic toxicity associated with conventional treatments make oncological therapy significantly difficult. In this context, nanomedicine emerges as a new approach in the prevention, diagnosis and treatment of cancer. In this work, pH-sensitive solid magnetoliposomes (SMLs) were developed for controlled release of the chemotherapeutic drug doxorubicin (DOX). Shape anisotropic magnetic nanoparticles of magnesium ferrite with partial substitution by calcium (Mg0.75Ca0.25Fe2O4) were synthesized, with and without calcination, and their structural, morphological and magnetic properties were investigated. Their superparamagnetic properties were evaluated and heating capabilities proven, either by exposure to an alternating magnetic field (AMF) (magnetic hyperthermia) or by irradiation with near-infrared (NIR) light (photothermia). The Mg0.75Ca0.25Fe2O4 calcined nanoparticles were selected to integrate the SMLs, surrounded by a lipid bilayer of DOPE:Ch:CHEMS (45:45:10). DOX was encapsulated in the nanosystems with an efficiency above 98%. DOX release assays showed a much more efficient release of the drug at pH = 5 compared to the release kinetics at physiological pH. By subjecting tumor cells to DOX-loaded SMLs, cell viability was significantly reduced, confirming that they can release the encapsulated drug. These results point to the development of efficient pH-sensitive nanocarriers, suitable for a synergistic action in cancer therapy with magnetic targeting, stimulus-controlled drug delivery and dual hyperthermia (magnetic and plasmonic) therapy. [ABSTRACT FROM AUTHOR]

In this work, a method of combinatorial variation of reactant solutions combined with an in situ UV-Vis readout of the plasmonic properties during the wet-chemical synthesis of Ag nanoprisms in micro fluid segments is presented. Segment sequences of clearly distinguishable compositions are generated by an automated flow rate program. By the help of two combined slowly shifting and two contrariwise rapidly changing reactant flow rates, a two dimensional parameter space is covered completely in steps of 20 %. Due to the sensitive main dipole mode of Ag nanoprisms, a combinatorial concentration variation during the growth step of the synthesis opens new possibilities regarding tuning of particle size and optical properties. Here, within one combinatorial synthesis run, silver nanoprisms with edge length between 35 and 200 nm and main plasmon resonances between 550 and 900 nm were obtained. [ABSTRACT FROM AUTHOR]