This is a copy of the slides presented at the meeting but not formally written up for the volume.

While certain types of nanotechnology applications have already been used in marketed products, it appears that the future holds many more opportunities for diverse applications of nanotechnology in products that will be regulated by the Food and Drug Administration (FDA). To this end, the FDA is taking steps to prepare for the arrival of these novel applications of nanotechnology. In the presentation, some of the steps taken by the FDA to meet the challenges of nanotechnology will be described. Specifically, challenges in nanotechnology applications for drug products and drug delivery systems will be considered. Scientific considerations that have taken place within the Center for Drug Evaluation and Research (CDER) will be discussed and some of the research projects initiated within CDER and focusing on better a understanding certain safety and characterization issues for nanotechnology materials will be mentioned.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

We present a novel approach which implements metallic nanoparticles for the development of a non-invasive opto-acoustic microscopy study of cells and bio-materials for the first time. The acoustic modes of metallic nanospheres dispersed inside a bio-matrix can be excited by a pump laser beam, resulting in acoustic oscillations with frequencies on the order of GHz. The acoustic oscillations can in turn be detected using transducers. We propose a new form of acoustic microscopy using such high frequency pulses in bio-materials. This is based on a recent demonstration by Ramanathan and Cahill of imaging with picosecond ultrasonic pulses generated by nanoscale metal thin films (J. Mater. Res. Rapid Comm. 21, 1204, 2006) We develop our concept with the goal of understanding the relationship between a cell’s structural and functional properties, the efficiency of drug treatments, the evolution of disease states, and detecting the existence of disease in a cell. For example, the elasticity of red blood cells infected with malaria undergoes significant change as the disease progresses (Suresh, J. Mater. Res. 21, 1871, 2006). The intimate connection between the progression of malaria in the red blood cell and the varying mechanical properties of the cell can be probed on a finer level using high resolution acoustic biomicroscopy. GHz range acoustic biomicroscopy would extend nondestructive imaging of cellular structure to the nanometer scale for the first time and open new directions for biological imaging research. The oscillations of the metallic particles can be understood within the context of Lamb’s theory of mechanical oscillations of elastic spheres. We use Lamb’s results and basic continuum mechanics to derive relationships between the laser energy deposited in the metallic particle and the amplitude of the resulting acoustic pulses. We model the pulses using Gaussian frequency spectra to understand the attenuation while propagating through a biological medium. The predictions for the pulse attenuation and amplitude are coupled to produce a preliminary theoretical understanding of the proposed opto-acoustic system. Our results show that bio-imaging using metallic nanoparticles are both feasible and promising. For distances on the scale of 10 microns, the length of a typical human red blood cell, the metallic nanoparticles can generate acoustic pulses with frequencies ranging up to 30 GHz. Such high frequency acoustic waves can in turn lead to imaging cellular phenomena at extremely high resolution. We anticipate that our approach will open innovative nanoscale techniques for non-invasive cellular research.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Since its market introduction roughly 30 years back, dynamic light scattering (DLS) has occupied a position of increasing popularity within the area of sub-micron particle and biopolymer characterization, due in large part to the non-invasiveness of the technique, the minimal sample volume & concentration requirements, and the quickness of data collection. Using ISO recommended measurement and analysis procedures, determination of the mean sample size and distribution width from DLS measurements is quite simple. In addition, modern instrumentation design and data interpretation software have removed much of the ?mystic? traditionally associated with this somewhat complex particle sizing technology. As a consequence, DLS instruments can now be routinely found in protein and nanoparticle laboratories around the globe. As might be expected, the simplicity of modern DLS instrumentation comes with a caveat. While calculation of the mean particle size for DLS is straight forward, extraction of further information, such as the intensity and/or volume (or mass) distribution is more convoluted, requiring the use of fitting algorithms. Data interpretation can be further complicated by the presence of noise, especially for samples with physical properties that are near the specified limits of the instrument/technique. This seminar covers the dos and don?ts of DLS data interpretation, and addresses the common question of ?what is the correct answer?.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

The National Institute of Standards and Technology, NIST, has an extensive nanotechnology portfolio to serve the measurement needs of its customers during every stage of technological innovation. This presentation will introduce the nanometrology program at NIST, emphasizing its impacts, both current and potential, on the biotechnology area. NIST’s main areas of focus will be described, as well as the influences of the needs of the biotechnology arena on the continual shaping of this program. NIST nanobiotechnology programs relate to the entire technological innovation continuum, from materials discovery/R&D through the end-use (and disposal) of a product. During the materials discovery and applied R&D stages, NIST measurement science provides many of the tools necessary to enable the components that will one day be inserted into commercialized products. NIST resources, such as the Advanced Measurement Laboratory (AML), provide measurement tools needed to increase the nation’s capability to understand phenomena at the nanoscale and accelerate technological innovation. NIST perspectives on measurement needs and solutions in the earlier stages of technological innovation will be discussed in the context of the nanobiotechnology sector. As nanobiotechnology products move toward the marketplace, the need for standards becomes clear, not only for potential FDA regulatory policy, but also for interlaboratory comparisons, and to support the development of assay protocols and other products anticipated from such organizations as NCL and ASTM. NIST work in standards and standard reference materials / reference materials (SRM/RM) will be discussed in this light. NIST priorities at all stages are strongly influenced by an understanding of the needs of the sectors to which it provides services. In this light, partnerships are extremely important in optimizing the path to providing appropriate techniques for application in nanobiotechnology. The NIST role in a NIST-NCI-FDA partnership will be presented as an example.Finally, a NIST perspective on the future of measurement science and technology work for nanobiotechnology will be presented.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Upconverting nanoparticles (UCNs) are modified nanometer-sized composites which generate higher energy visible light from lower energy radiation (usually near-infrared (NIR)) by non-radiative transfer of photons between transition metal, lanthanide, or actinide ions doped into a solid-state host. These nanoparticles offer several advantages as imaging probes for live cells and tissues: high sensitivity of detection due to absence of autofluorescence from tissues, sharp emission peaks, less toxic components (than quantum dots (QDs)) and high depth of penetration and low phototoxicity of NIR light. Although the use of upconverting phosphors in nucleic acid assays, immunohistochemistry and immuno-assays have been demonstrated, no reports exploiting the advantages of these labels in live mammalian cell and tissue imaging have been demonstrated. Moreover, these assays usually utilize large sized reporters (>400nm). In this report, we present the synthesis and characterization of UCN and explore their effectiveness as live cellular and tissue labels. Nanoparticles with a nanocrystalline NaYF4 core doped with Yb3+ and Er3+ and coated with high molecular weight (25 kDa) PEI as surfactant was synthesized using a simple ‘one pot’ hydrothermal method. After characterization and biocompatibility tests, the UCN were conjugated to folic acid and targeted to mammalian breast carcinoma cells. To demonstrate tissue imaging, UCN were injected into live mouse and rat tissues and excited using a simplified NIR laser set-up. The nanoparticles obtained were spherical, about 50nm in diameter and with a narrow size distribution. They demonstrated sharp emission peaks at 653nm and 540nm when excited with a 980nm laser, and excellent stability when stored in phosphate buffered saline or incubated with complete serum at 37 deg C. The particles were found to be biocompatible with different cell types at different concentrations when incubated over varying time periods. Upon incubation, mammalian cancer cells took up the UCN and were imaged with high signal-to-background ratios. Continuous imaging of live cells could be performed without cell damage or death. UCN was injected into mouse skin and leg muscles and excited with NIR laser set at low power to prevent tissue damage. Visible phosphorescence was recorded from both sites. Phosphorescence could also be seen when UCN was injected in the skin and to a small depth of penetration in some muscles of rats.We conclude that these upconverting nanoparticles are promising labels for use in live cell and tissue imaging.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

In order to characterize and control the adhesive behaviors of nanometer scaled stimuli-responsible gel particles designed for oral peptide delivery, their interaction with artificial mucin layer in the small intestinal solutions was determined by the colloid probe atomic force microscope method. The prepared nanometer scaled gel particles with a core-shell structure were designed to exhibit behaviors responsive to temperature and pH in solutions, consequently protect the incorporated peptide drug under harsh acidic conditions in the stomach, adhere and penetrate to the mucin layer in the small intestine, and thereafter release the drugs. Spherical agglomerates of the nano-gel particles with several micron meters in diameter were prepared by the spray freeze drying method and adhered on the top of tip of commercial atomic force microscope. The interaction between the artificial mucin layer and nano-gel surface with different molecular structure of shell determined by the colloid probe method depended on pH and counter-ion concentration of the solution. Based on the possible transition of the surface-microstructure of nano-gel particles following the pH change and the measured results from the colloid probe AFM method, the relationship between surface interaction and microstructure of nano-gel was discussed.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Cerium oxide (ceria) can be considered as one of the most important rare earth oxides. In conjunction with the benefits of nanotechnology, it has found enormous applications in catalysis, sensors and biomedical applications. These applications stem from its ability to switch oxidation states between +3 and +4 depending on ambient conditions. Nanoceria has been shown to impart protection to cells against the reactive oxygen species (ROS) by our group. We have also established a preferential protection of the normal cells against radiation damage as compared to the tumor cells. These stimulating properties of nanoceria make it imperative to stabilize it in various aqueous and non-aqueous solvents for practical applications. Systematic engineering of nanoceria in media like poly (ethylene glycol) (PEG), dextran and glucose can be of great importance in biological applications. Dextran and PEG have been used extensively to stabilize nanoparticles in solution. Biocompatibility of these media can be exploited to disperse nanoceria inside the body to provide cell protection. Unlike most of the reported work, where a two step synthesis and re-dispersion strategy is used, nanoceria prepared under room temperature wet chemical synthesis shows active switching of oxidation states. In the present work we report the successful synthesis of nanoceria in glucose, dextran and their effect on stability of nanoparticles in acidic and basic media. The role of polyhydroxyl group in complexing ceria and their subsequent oxidation/hydrolysis is monitored using UV-VIS spectroscopy. The nanoparticle characterization using high resolution transmission electron microscopy (HRTEM) for structure and morphology and X-ray Photoelectron Spectroscopy (XPS) for oxidation states will be reported. An effort will be made to present the quantitative analysis of various results.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Nanomedicine encompasses a vast area of biomedical research, from the development of new generation of contrast agents for diagnostic imaging to synthesizing targeted delivery vehicles of therapeutic drugs. This talk will highlight the use of multifunctional nanoparticles with combined imaging, diagnostic and therapeutic functions for nanomedicine. In our Institute we are developing new optical nanoprobes for bioimaging. They include functionalized quantum dots, aggregation-enhanced two photon dyes as well as nanocomposite nanoparticles with combined optical, magnetic, plasmonic and PET imaging capabilities. The goal is to provide targeting nanoprobes for early detection of diseases as well as for real time monitoring of a disease progression or the progress of a therapy. The organically modified silica (ORMOSIL) nanoparticles have been developed as a new-generation drug carrier for photodynamic therapy (PDT) of cancer, as well as for an efficient non-viral gene delivery, capable of transfecting neuronal cells in vivo with superior efficacy over viral vectors.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Several programs in the NCI nanotech seek to develop unique platforms for targeted drug delivery. These platforms involve the use of nanometer-sized macromolecules and nanoparticles. Requirements should include a diameter small enough that the drug and carrier will escape the blood stream through vascular pores and then specifically target cells within tumors or selected organs. Importantly, these platforms should also internalize within a cell and localize to intracellular structures. Achieving proof of concept with these technologies would then require additional funding from venture capital or private corporate investment to support human clinical trials. Given the activity of nanoparticles for drug, this technology has the potential to revolutionize therapeutics and provide unique solutions for all aspects of cancer care. The potential risks, benefits and technical requirements for these platforms will be reviewed. Different technologies will be compared and contrasted for the ability to meet the need of cancer therapeutics.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Superparamagnetic iron oxide (SPIO) nanoparticles are prevalent as nanoprobes for molecular magnetic resonance imaging (MRI), providing positive or negative contrast by locally affecting the relaxation of water protons. Fe3O4 nanoparticles are commonly used as a negative MRI contrast agent, implementing various surface functionalization techniques to provide molecular targeting to biological macromolecules. The authors recently demonstrated targeting of cancer antigen 125 (CA125) with differentiable MRI contrast in human ovarian cancer cell lines using monoclonal antibodies covalently conjugated to phospholipid micelle encapsulated 10 nm single crystalline SPIO nanoparticles, demonstrating molecular targeting capabilities via surface functionalization [1]. While molecular targeting of SPIO nanoparticles has been thoroughly demonstrated, the effects of surface modifications have not been studied in regard to proton relaxation. The authors will present spin-lattice (T1) and spin-spin (T2) proton relaxometry of SPIO nanoparticles with varying surface chemistries. The effects of surface modification on T1 and T2 relaxation have not been thoroughly investigated, and results recently reported by the authors indicate a correlation of spin-spin relaxation with SPIO nanoparticle hydrodynamic radius [2]. T1 and T2 relaxometry (Varian 300 MHz NMR) of polyethylene glycol modified (PEGylated) phospholipid micelle encapsulated SPIO nanoparticles and covalently PEGylated SPIO nanoparticles for varying hydrodynamic radii will be presented. These results are of particular interest to molecular imaging applications due to the common practice of SPIO nanoparticle PEGylation to improve biocompatibility. The authors will also present results of magnetic anisotropy studies with respect to proton relaxation by SPIO nanoparticles. Recent work by Roch et al emphasizes the role of magnetic anisotropy in the proton relaxation mechanism of SPIO nanoparticles [3]. The authors have synthesized monodisperse Fe3-xCoxO4 nanoparticles with similar properties to SPIO. Cobalt substitution in SPIO nanoparticles increases the magnetic anisotropy of the SPIO nanoparticles, thus affecting the proton relaxation. The authors will present T1 and T2 relaxometry (Varian 300 MHz NMR) of Fe3-xCoxO4 nanoparticles and corresponding SQUID (superconducting quantum interference device) magnetic anisotropy measurements (Quantum Design, MPMS-7). The results of this study elucidate the role of magnetic anisotropy in the proton relaxation mechanism and demonstrates the feasibility of Fe3-xCoxO4 nanoparticles as a T2 contrast agent.1. Larsen BA et al, Proceedings of the 5th Annual Meeting of Molecular Imaging, 20062. Barker AJ, Larsen BA et al, Proceedings of the ASME SBC, 20063. Roch et al, Journal of Mag Res Imaging 14, pp 94-96, 2001.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Proteomics based clinical diagnostics systems utilize the principle of protein identification as a means of biomarker profiling for disease diagnosis. The current standardized immunoassay techniques such as Enzyme linked Immunosorbent Assays (ELISA) are based on the fluorescent detection of the antibody (Ab)-antigen (Ag) binding event. These techniques are expensive; time consuming requiring a large sample volume. We present here two electrical immunoassay techniques that can potentially used for the rapid, multiplexed diagnosis of proteins for disease identification. The first technique involves the use of nanoporous templates in conjunction with microfabricated platforms with metallic base electrodes resulting In the formation of a “nanowell” assay system that is analogous to the micro titer well plate system. The detection of the formation of binding complex is achieved by capacitive measurement techniques. The dynamic range and the calibration of the device has been performed with respective to the current gold standard in proteomics. The second technique involves the use of microscale carriers to transport ab’s to sensing sites on microfabricated base platforms. The binding of the Ag’s to the Ab’s coupled to the carriers’ results in measurable voltage changes that are recorded in a real time manner. The calibration and the dynamic range of this device has also been determined. Both these techniques demonstrate potential as early diagnostic devices and their performance in detection of clinically relevant proteins is demonstrated.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Tissue scaffolds have recently demonstrated widespread application in injury healing due to their biomimetic properties and their structural resemblance to the extracellular matrix in cell re-growth. The investigation of cell response to biomimetic triggers provided by tissue scaffolds will greatly extend the impact of this field.

In this paper, the response of 3T3 NIH fibroblasts to 2D planar surfaces versus their response to nanofiber mat surfaces, which have 3D effects, are investigated. A difference in cell shape from triangular cell body with prominent vertices to triangular cell body with blunted vertices and increased cell-cell adhesions at such vertices was observed using fluorescent microscopy, optical microscopy and atomic force microscopy. A new and powerful atomic force microscopy technique developed by our group, Scanning Probe Recognition Microscopy, is introduced and implemented to directly recognize and auto-focus on fibroblast vertex regions.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Interest in nanotechnology is rapidly growing as applications for nanoparticles in drug delivery and as image contrast agents are realized. Nanoparticles, as the name implies, refers to particles with sizes ranging from a few nanometers to hundreds of nanometers. Based on this definition, it is size which differentiates nanoparticles from all other particles. Also, it is size which will contribute to the properties of the nanoparticles and determine ultimately its function and efficacy in real-world applications. Thus it is important to properly characterize the size of nanoparticles. Light scattering (static and dynamic) is a non-invasive technique for measuring particle size and size distribution in solution. Measurements can be made in batch or flow mode. In the case of batch mode, the average size of the nanoparticle is determined. Thus if the sample contains impurities or aggregates, the size would be skewed and inaccurate. To accurately determine size, some type of separation would be needed. Size Exclusion Chromatography (SEC) is a separation technique used for determining purity of a sample and is based on the molecular size of the sample components. Coupled with a multiple angle laser light scattering (MALLS) and inline dynamic light scattering (DLS) apparatus, the size can be determined for the fractionated sample. The sizes of several different nanoparticles were measured in batch and flow mode and the implications of the size results are discussed. Nanoparticles studied include dendrimers, liposomes, and metal particles. Finally, these results are used to establish standard protocols for size characterization of nanoparticles.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Size exclusion chromatography (SEC) and dynamic light scattering (DLS) are two technologies common to protein laboratories. SEC is routinely used for purification, identification, and quantification of protein mixtures, while batch DLS is routinely used for pre-column size & polydispersity measurements, along with aggregate quantification. The coupling of DLS & SEC technologies has been difficult, due in large part to the fact that eluted protein sample concentrations tend to be well below the detection limit for most dynamic light scattering instruments. As highlighted and discussed in the paper presented here however, the latest generation of DLS systems, specifically the high sensitivity Zetasizer Nano from Malvern Instruments, has proven itself capable of handling this low protein concentration challenge. As a consequence, size exclusion chromatography systems can now be directly coupled with high sensitivity DLS instrumentation, thereby providing an “absolute” measure of the hydrodynamic size and minimizing the common headaches of SEC measurements such as packing material interactions and shape effects.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Antibodies are specialized proteins that function as an essential part of the immune system and usually target specific receptors, making them ideal for the development of drug candidates. They are members of a class of proteins known as immunoglobulins, typically with a molecular size near ~10nm. This preclinical characterization shows the advantages of dynamic light scattering (DLS) both as a standalone method and in conjunction with chromatographic separation. We show data demonstrating the effect of different storage conditions and sample treatment, leading to different size distributions. Behaviour as a function of temperature shows a clear melting or aggregation point, above which the molecules assemble into larger structures. Higher melting points are correlated with higher stability. Size distribution data may be compared with results obtained from analytical ultracentrifugation (AUC) ? but at much faster acquisition time of minutes instead of hours. We have also combined light scattering with chromatography to show the separation of antibodies and Fab fragments. Here, the resolving power of the separation method allows us to distinguish the fragments (about ~5nm size) from the ?intact? molecules. Dynamic light scattering is a versatile measurement technique and ideally suited as a metrology of choice for size and stability of nano-sized materials.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

To address the needs of a wide variety of potential application domains, the sophistication and structural complexity of engineered nanoparticle systems has been steadily increasing. Often the unique functionality of these systems depends on the 3-dimensional distribution of multiple phases, ranging from simple coatings to core-shell morphologies to multifunctionalizations for drug delivery. This need for controlled 3-dimensional chemical heterogeneity at the nanoscale presents significant challenges both for the nanomanufacturing of these materials and their metrology and characterization. Even when the nanoparticles have relatively simple structures, the demands of modern process control methodologies and the specifications of end users frequently require increased metrology precision and decreased measurement bias for critical measurands such as coating thicknesses or particle size distributions. Recent advances in electron microscopy and focused ion beam (FIB) technology provide powerful tools for the 3-dimensional structural and elemental characterization of nanomaterials. Dimensional metrology using phase contrast high-resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) can measure the physical dimensions of nanostructures at the single nanometer level. Elemental mapping using energy-filtered TEM (EFTEM) can be used to map the spatial distribution of different stoichiometries, while electron tomography can reconstruct the 3-dimensional morphology of nanoparticle assemblies. Examples of the above techniques will be presented along with recent NIST efforts to fuse these techniques into a methodology for 3-dimensional chemical imaging of engineered nanostructures.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Nanotechnology is expected to have a revolutionary impact on medical diagnosis and therapy. In cancer therapy, targeting and localized delivery are the key challenges. To wage an effective war against cancer, we have to have the ability to selectively attack the cancer cells, while saving the normal tissue from excessive burdens of drug toxicity. In this presentation, I will discuss the different nanotechnology platforms that we have developed for targeted drug and gene delivery to tumor mass. Special emphasis will be placed on nano-platforms that offer opportunities for multi-functionalization to allow for simultaneous strategic delivery of multiple therapeutic agents or combining imaging and therapeutic modalities. Results from our laboratory at Northeastern University show that polymer- and lipid-based nanosystems can provide versatile platforms for delivery of multiple therapeutic agents, specifically to enhance therapeutic effect and overcome drug resistance in cancer. In addition, polymeric nanoparticles are used for tumor-targeted anti-angiogenic gene therapy. Nanoemulsions, made from oils rich in polyunsaturated fatty acid, offer an opportunity to facilitate transport across biological barriers for targeted delivery of drugs and imaging agents. Lastly, I will discuss our work on gold and iron oxide-gold nanostructures that are functionalized for targeted imaging and drug delivery applications.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

New biomolecular-inorganic nanohybrids with two different functions, one from inorganic moiety and the other from biological one were realized by soft chemical methods such as intercalation, coprecipitation and exfoliation-reassembling reactions. Recently we have been focusing on two-dimensional inorganic compounds like layered double hydroxides (LDHs), since they are biocompatible and can be used as gene or drug delivery inorganic nanovehicles. To the best of our knowledge, such inorganic drug delivery vectors are quite different from conventionally developed ones such as viral based vectors, naked DNA, biodegradable polymers,liposomes, and etc, those which are however limitedly used due to their toxicity, immunogenecity, poor integration, and etc. But we found that such disadvantages can be overcome by immobilizing genes or drug molecules into these new inorganic vectors, which consist of non-toxic metal ions with biological compatibility. Since LDHs are anion exchangeable, negatively charged functional biomolecules can be easily intercalated into hydroxide layers of LDHs by soft chemical reaction methods to form bio-LDHs nanohybrids. In such a way they can gain extra stabilization energy due to the electrostatic interaction between inorganic layers, whatever they are anionic or cationic, and counter-charged biomolecules or drugs. We also found that the hydroxide layers of LDHs could protect the intercalated molecules very efficiently. If necessary, inorganic materials, as reservoir and delivery carrier, can be intentionally removed by dissolving them in an acidic or basic media, which offer a way of recovering the encapsulated biomolecules or drugs. The possible roles of inorganic lattice as the gene and drug delivery carrier will be shown by demonstrating the cellular uptake experiments of FITC, fluorophore, with laser scanning confocal fluorescence microscopy as well as of radioactive isotope-labeled ATP-LDH hybrid. As the typical examples for gene and drug delivery systems, As-myc-LDH and MTX-LDH nanohybrids will be demonstrated along with their endocytic mechanism. In addition, nanotoxicity of LDH and other inorganic nanoparticles will be also discussed in detail.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

As in vivo cellular imaging becomes the necessary norm for understanding cancer and other diseases, new non-toxic nanoprobes are going to be required to replace the high quality cadmium based nanoprobes in use today. We are developing less toxic probes based on two types of luminescent ceramic nanoparticles: naturally occurring fluorescent (NOF) mimics and Ln-based ceramic oxide materials. The NOF minerals of interest and that have demonstrated initial luminosity of sufficient brightness for use in cellular studies that include sphalerite, scheelite, manganoan and perovskite nanoparticles. For Ln-based materials we have shown that Ln-doped zincite will also luminesce enough to allow for quantification in cellular activity. Once formed, these probes are functionalized such that they can be delivered to desired cellular targets. Probe derivatization has focused on surface capping with functionalized poly(ethyleneglycol) molecules/lipids to yield water soluble NCs and polyarginine-based transporters for transmembrane delivery. The probes are being evaluated for their luminescent properties, as well as their non-toxicity and ability to report on cell-signaling events with various cell lines using multi-spectral, confocal microscopy, and other techniques. Preliminary interdisciplinary studies have validated the basic approaches for the synthesis of NOF nanoprobes and the bio-delivery and imaging of nanoparticles. Work to optimize the design, delivery, and imaging of these new nanoprobes is expected to achieve the NIH directed goal of increasing in the sensitivity and specificity of molecular probes for imaging. Details of the synthesis, functionalization and biological imaging using these probes will be presented. This work partially supported by the United States Department of Energy under contract number DE-AC04-94AL85000. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the United States Department of Energy and by the National Institutes of health through the NIH Roadmap for Medical Research, Grant #1 R21 EB005365-01. Information on this RFA (Innovation in Molecular Imaging Probes) can be found at http://grants.nih.gov/grants/guide/rfa-files/RFA-RM-04-021.html.