Biocompatible magnetic nanoparticles hold great therapeutic potential, but conventional particles can be toxic. Here, we report the synthesis and alternating magnetic field dependent actuation of a remotely controllable, multifunctional nano-scale system and its marked biocompatibility with mammalian cells. Monodisperse, magnetic nanospheres based on thermo-sensitive polymer network poly(ethylene glycol) ethyl ether methacrylate-co-poly(ethylene glycol) methyl ether methacrylate were synthesized using free radical polymerization. Synthesized nanospheres have oscillating magnetic field induced thermo-reversible behavior; exhibiting desirable characteristics comparable to the widely used poly-N-isopropylacrylamide-based systems in shrinkage plus a broader volumetric transition range. Remote heating and model drug release were characterized for different field strengths. Nanospheres containing nanoparticles up to an iron concentration of 6 mM were readily taken up by neuron-like PC12 pheochromocytoma cells and had reduced toxicity compared to other surface modified magnetic nanocarriers. Furthermore, nanosphere exposure did not inhibit the extension of cellular processes (neurite outgrowth) even at high iron concentrations (6 mM), indicating minimal negative effects in cellular systems. Excellent intracellular uptake and enhanced biocompatibility coupled with the lack of deleterious effects on neurite outgrowth and prior Food and Drug Administration (FDA) approval of PEG-based carriers suggest increased therapeutic potential of this system for manipulating axon regeneration following nervous system injury.

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Quantum dots (QDs) have received attention for labeling biomolecules; however, toxicity of these nanostructures in the intracellular environment has prevented a biomedical breakthrough. Here we report biocompatibility of a QD based multifunctional system on neuronal cells. Moreover, the designed nanostructures bind with high affinity in the cell nucleus. Nucleus specific binding and enhanced biocompatibility, coupled with no deleterious effects on neurite outgrowth, even at high dosages (500 μg/ml sphere conc.) suggest increased therapeutic potential of this system for specific targeting followed by controlled release of drugs in treating neurodegenerative disorders.

The use of high intensity chemo-radiotherapies has demonstrated only modest improvement in the treatment of high-risk neuroblastomas. Moreover, undesirable drug specific and radiation therapy-incurred side effects enhance the risk of developing into a second cancer at a later stage. In this study, a safer and alternative multimodal therapeutic strategy involving simultaneous optical and oscillating (AC, Alternating Current) magnetic field stimulation of a multifunctional nanocarrier system has successfully been implemented to guide neuroblastoma cell destruction. This novel technique permitted the use of low-intensity photo-magnetic irradiation and reduced the required nanoparticle dose level. The combination of released cisplatin from the nanodrug reservoirs and photo-magnetic coupled hyperthermia mediated cytotoxicity led to the complete ablation of the B35 neuroblastoma cells in culture. Our study suggests that smart nanostructure-based photo-magnetic hybrid irradiation is a viable approach to remotely guide neuroblastoma cell destruction, which may be adopted in clinical management post modification to treat aggressive cancers.

Hydrogel based Quantum dots (QD) has become an interesting subject of study for labeling and drug delivery in biomedical research due to their unique responses to the external stimuli. In this paper, biological effect of a novel hydrogel based QD nanomaterial system on Escherichia coli (E. coli) bacteria is presented. The experimental evidence shows that appropriately coated CdTe QDs has reduced or negligible toxicity to this model cell system, even when exposed to higher dosages. Thus, coated QDs that possess tunable packing density have the potential to control system efficiency and may be suitable for various biomedical applications.