Photothermal therapy (PTT) using plasmonic nanoparticles for cancer treatment is on the verge of clinical application. Titanium nitride (TiN) nanoparticles offer a promising alternative to commonly used gold-based systems at a fraction of the costs. Little is known, however, about the relationship between TiN particle characteristics and their optical properties in colloidal systems. Here, TiN nanoparticles with closely controlled characteristics are prepared by nitridation of TiO 2 , and their use as PTT agents is explored. Emphasis is placed on the particle surface and core oxygen content, which dominate the TiN optical properties. Colloidal suspensions were studied under UV−vis and near-infrared (NIR) laser irradiation and correlated to particle characteristics. High nitridation temperatures and long residence times lead to increased NIR light absorption. Too high nitridation temperatures, however, lead to particle aggregation that deteriorated their optical properties. This was overcome with SiO 2 coating of TiO 2 nanoparticles prior to nitridation: the resulting SiO 2coated TiN particles exhibited increased plasmonic performance compared to bare TiN, which is attributed to reduced plasmonic coupling effects. The optimized SiO 2 -coated TiN had a photothermal efficiency of 58.5% and mass extinction coefficient of 31.6 L g −1 cm −1 , outperforming commercial gold nanoshells that are used in clinical trials. The potential of SiO 2coated TiN for photothermal therapy was demonstrated by controllably killing HeLa cells in vitro.

Low-molecular weight chitosan-thioglycolic acid has shown significant antibacterial properties against different microorganisms. In order to explore the potential and structure-activity relationships of newly synthesized alkyl thiomers, chitosan has been functionalized with a series of thio-acids with increasing alkyl chain length. All thiomers were characterized with special emphasis on the determination of their degree of deacetylation and substitution, as well as on their molecular weight and amount of thiol groups. The pre-screened chitosan-thiomers were further investigated with plate counting on Pseudomonas aeruginosa, Streptococcus sobrinus and Streptococcus mutans. Furthermore, LIVE/DEAD assays supported the efficiency of chitosan-thiomers against the above microorganisms. All fully characterized chitosan-thiomers showed comparable or enhanced antimicrobial activity compared to pristine chitosan. Our comprehensive approach paves the way to detailed explorations of much sought-after structure activity relationships in the complex chitosan parameter room, starting from correlations between alkyl chain length and antimicrobial activity.

Representative polyoxometalates with proven bioactive properties, namely {Sb 9 W 21 }, {P 2 W 18 } and {Mo 7 O 24 }, were encapsulated into chitosan and carboxymethyl chitosan (CMC) to afford nanoscale composites. The pristine POMs were characterized with a wide range of analytical techniques, including powder X-ray diffraction as well as FT-IR and 31 P NMR spectroscopy. Size and morphology of their nanocomposites were determined within the 100-200 nm size range by dynamic light scattering (DLS) methods in combination with scanning and transmission electron microscopy. Their stability was monitored i Pr] 6 [Mo 7 O 24 ]·3H 2 O is the most widely investigated representative [in the following referred to as {Mo 7 O 24 }]. [13] It was found to be active in vivo and in vitro against different mouse models of cancer. [13,14] The proposed mechanism is based on induced cell death via ATP synthesis inhibition [15] that is caused by reduced H x Mo 7 O 24 spe- [a]

Anionic poly(vinylcaprolactam-co-itaconicacid-co-dimethylitaconate) microgels were synthesized via dispersion polymerization and their responsiveness towards cations, namely Mg2+, Sr2+, Cu2+ and Fe3+ was investigated. The itaconic moeities chelate the metal ions which act...

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