Innovation in the last decade has endowed nanotechnology with an assortment of tools for delivery, imaging, and sensing in cancer research-stealthy nanoparticle vectors circulating in vivo, assembled with exquisite molecular control, capable of selective tumor targeting and potent delivery of therapeutics; intense and photostable quantum dot-based tumor imaging, enabling multicolor detection of cell receptors with a single optical excitation source; arrays of semiconducting nanowire and carbon nanotube sensor elements for selective multiplexed sensing of cancer markers without the need for probe labeling. These rapidly emerging tools are indicative of a burgeoning field ready to expand into medical applications. This review attempts to outline most of the current nanoparticle toolset for therapeutic release by liposomes, dendrimers, smart polymers, and virus-based systems. Advantages of nanoparticle-based imaging and targeting by use of nanoshells and quantum dots are also explored. Finally, emerging nanoelectronics-based sensing and a global discussion on the utility of each nanoparticle system addresses their fundamental advantages and shortcomings in cancer research.

We demonstrate the use of surface Zeta potential measurements as a new tool to investigate the interactions of iron oxide nanoparticles and cowpea mosaic virus (CPMV) nanoparticles with human normal breast epithelial cells (MCF10A) and cancer breast epithelial cells (MCF7) respectively. A substantial understanding in the interaction of nanoparticles with normal and cancer cells in vitro will enable the capabilities of improving diagnostic and treatment methods in cancer research, such as imaging and targeted drug delivery. A theoretical Zeta potential model is first established to show the effects of binding process and internalization process during the nanoparticle uptake by cells and the possible trends of Zeta potential change is predicted for different cell endocytosis capacities. The corresponding changes of total surface charge of cells in the form of Zeta potential measurements were then reported after incubated respectively with iron oxide nanoparticles and CPMV nanoparticles. As observed, after MCF7 and MCF10A cells were incubated respectively with two types of nanoparticles, the significant differences in their surface charge change indicate the potential role of Zeta potential as a valuable biological signature in studying the cellular Biomed Microdevices

Viruses are exemplary models in nanoassembly for their regular geometries, well characterized surface properties, and nanoscale dimensions. Armed with versatile tools aimed at site-directed mutagenesis to modify the virion's surface, conjugation chemistry for capsid coupling, and manipulation of nanoparticles, we have demonstrated nanoscale assembly of inorganic carbon nanotubes and quantum dots with engineered viruses to produce an intimate array of hybrid structures.

We have developed a substrate-based bottom-up approach to assemble two different color emitting quantum dots (CdSe/ZnS core/shell QDs) on the surface of a novel virus mutant, CPMV-T184C. Electrical characteristics of individual hybrids were investigated by conductive atomic force microscopy for potential digital memory applications (i.e., RAM). These individual 40 nm CPMV-QD(1,2) hybrids exhibited reversible bistable electrical behavior during repeatable writing-reading-erasing processes at the nanoscale.