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Recently, superparamagnetic chemically disordered face-centered cubic (fcc) FePt nanoparticles have been demonstrated as superior negative contrast agents for magnetic resonance imaging (MRI). However, their low intracellular labeling efficiency has limited the potential usage and the nanotoxicity of the particles requires attention. We have developed fluorescein isothiocyanate-incorporated silica-coated FePt (FePt@SiO2-FITC) nanoparticles that exhibited not only a significantT1andT2MR contrast abilities but also a fluorescent property without significant cytotoxicities. These results suggest that silica-coated superparamagnetic FePt nanoparticles are potential nanodevices for the combination of fluorescence and MRI contrast used for cancer diagnosis.

Manganese-zinc ferrite (MZF) is known as high-performance magnetic material and has been used in many fields and development. In the biomedical applications, the biocompatible MZF formulation attracted much attention. In this study, water-soluble amphiphilic vitamin E (TPGS, d-alpha-tocopheryl poly(ethylene glycol 1000) succinate) formulated MZF nanoparticles were synthesized to serve as both a magnetic resonance imaging (MRI) contrast agent and a vehicle for creating magnetically induced hyperthermia against cancer. The MZF nanoparticles were synthesized from a metallic acetylacetonate in an organic phase and further modified with TPGS using an emulsion and solvent-evaporation method. The resulting TPGS-modified MZF nanoparticles exhibited a dual-contrast ability, with a longitudinal relaxivity (35.22 s−1 mM Fe−1) and transverse relaxivity (237.94 s−1 mM Fe−1) that were both higher than Resovist®. Furthermore, the TPGS-assisted MZF formulation can be used for hyperthermia treatment to successfully suppress cell viability and tumor growth after applying an alternating current (AC) electromagnetic field at lower amplitude. Thus, the TPGS-assisted MZF theranostics can not only be applied as a potential contrast agent for MRI but also has potential for use in hyperthermia treatments.

The vigorous, exothermic decomposition of methyl ethyl ketone peroxide (MEKPO) can be stimulated by acids, metals, or heat, and the initial stage is critical to runaway reactions. Real-time thermal data are important in the evaluation of the hazards of fast reactions during the initial stage. We report the first real-time observation of the reaction of MEKPO with inorganic acids using a thermal imaging camera (TIC), which we used to determine the rate of heat evolution and to recognize the degree of the hazard present during accidents. In addition, ab initio computational methods were used to estimate the thermokinetic parameters for the proposed reaction mechanisms. The results indicated that the temperature of the solution, the concentration of the acid, and the dehydration ability were the primary factors that affected the thermal reaction. This work provides a new method to study thermal chemistry and to evaluate thermal hazards

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