Metabolomics based markers predict type 2 diabetes in a 14-year follow-up study

Chemical probes are key components of the bioimaging toolbox, as they label biomolecules in cells and tissues. The new challenge in bioimaging is to design chemical probes for three-dimensional (3D) tissue imaging. In this work, we discovered that light scattering of metal nanoparticles can provide 3D imaging contrast in intact and transparent tissues. The nanoparticles can act as a template for the chemical growth of a metal layer to further enhance the scattering signal. The use of chemically grown nanoparticles in whole tissues can amplify the scattering to produce a 1.4 million-fold greater photon yield than obtained using common fluorophores. These probes are non-photobleaching and can be used alongside fluorophores without interference. We demonstrated three distinct biomedical applications: (a) molecular imaging of blood vessels, (b) tracking of nanodrug carriers in tumors, and (c) mapping of lesions and immune cells in a multiple sclerosis mouse model. Our strategy establishes a distinct yet complementary set of imaging probes for understanding disease mechanisms in three dimensions

Parametric Study on Dimensional Control of ZnO Nanowalls and Nanowires by Electrochemical Deposition

A simple electrochemical deposition technique is used to synthesize both two-dimensional (nanowall) and one-dimensional (nanowire) ZnO nanostructures on indium-tin-oxide-coated glass substrates at 70°C. By fine-tuning the deposition conditions, particularly the initial Zn(NO3)2·6H2O electrolyte concentration, the mean ledge thickness of the nanowalls (50–100 nm) and the average diameter of the nanowires (50–120 nm) can be easily varied. The KCl supporting electrolyte used in the electrodeposition also has a pronounced effect on the formation of the nanowalls, due to the adsorption of Cl− ions on the preferred (0001) growth plane of ZnO and thereby redirecting growth on the (100) and (20) planes. Furthermore, evolution from the formation of ZnO nanowalls to formation of nanowires is observed as the KCl concentration is reduced in the electrolyte. The crystalline properties and growth directions of the as-synthesized ZnO nanostructures are studied in details by glancing-incidence X-ray diffraction and transmission electron microscopy

Make Nanomedicine Great Again ...... By Understanding Biological Barriers To Drug Delivery

Cancer targeting nanoparticles face a variety of biological environments between the site of injection and cancer cells. While researchers can measure the properties of nanoparticles outside the body, interactions with biological environment and its effect on nanoparticle tumour delivery remains unexplored. Understanding these barriers for cancer nanomedicine is the first step towards overcoming them. Here, I focus on three aspects of 3 nano-bio interactions enroute to cancer that dictates its biological fate: 1) Nanoparticle-Blood: Serum protein adsorption on circulating nanoparticles can be used as input to develop a supervised learning algorithm that can predict the fate of nanoparticles. This model achieved 77-95% accuracy in its prediction and altering the proteins on the surface led to reduction in liver and spleen uptake. 2) Nanoparticle – Tumour Blood Vessels: The dominant mechanism of nanoparticle entry into solid tumours is trans-endothelial and not through inter-endothelial gaps via Enhanced Permeation and Retention (EPR) effect. Upto 97% of nanoparticles were found to extravasate into the tumour via trans-endothelial pathways. This changes our approach to developing cancer nanomedicine as we now have to utilize this active mechanism instead of relying of passive accumulation. 3) Nanoparticle-Tumour: We have developed an approach that allows 3D imaging of nanoparticles in intact tumours. This technique is high throughput, cost effective and is compatible with both organic and inorganic nanoparticles. This is now allowing us to map all the barriers to cancer nanomedicine in tumours. This map is powerful because it forms the basis for classifying tumours into zones of varying nanoparticle distribution and can make accurate predictions of nanoparticle targeting efficiency. The work presented here arms the field of cancer nanomedicine with the biological barriers that need to be taken into design considerations to improve its clinical translation.Ph.D.2020-12-09 00:00:0

Exploring Passive Clearing for 3D Optical Imaging of Nanoparticles in Intact Tissues

The three-dimensional (3D) optical imaging of nanoparticle distribution within cells and tissues can provide insights into barriers to nanoparticle transport in vivo. However, this approach requires the preparation of optically transparent samples using harsh chemical and physical methods, which can lead to a significant loss of nanoparticles and decreased sensitivity of subsequent analyses. Here, we investigate the influence of electrophoresis and clearing time on nanoparticle retention within intact tissues and the impact of these factors on the final 3D image quality. Our findings reveal that longer clearing times lead to a loss of nanoparticles but improved transparency of tissues. We discovered that passive clearing improved nanoparticle retention 2-fold compared to results from electrophoretic clearing. Using the passive clearing approach, we were able to observe a small population of nanoparticles undergoing hepatobiliary clearance, which could not be observed in liver tissues that were prepared by electrophoretic clearing. This strategy enables researchers to visualize the interface between nanomaterials and their surrounding biological environment with high sensitivity, which enables quantitative and unbiased analysis for guiding the next generation of nanomedicine designs

Three-Dimensional Optical Mapping of Nanoparticle Distribution in Intact Tissues

The role of tissue architecture in mediating nanoparticle transport, targeting, and biological effects is unknown due to the lack of tools for imaging nanomaterials in whole organs. Here, we developed a rapid optical mapping technique to image nanomaterials in intact organs <i>ex vivo</i> and in three-dimensions (3D). We engineered a high-throughput electrophoretic flow device to simultaneously transform up to 48 tissues into optically transparent structures, allowing subcellular imaging of nanomaterials more than 1 mm deep into tissues which is 25-fold greater than current techniques. A key finding is that nanomaterials can be retained in the processed tissue by chemical cross-linking of surface adsorbed serum proteins to the tissue matrix, which enables nanomaterials to be imaged with respect to cells, blood vessels, and other structures. We developed a computational algorithm to analyze and quantitatively map nanomaterial distribution. This method can be universally applied to visualize the distribution and interactions of materials in whole tissues and animals including such applications as the imaging of nanomaterials, tissue engineered constructs, and biosensors within their intact biological environment

Three-Dimensional Imaging of Transparent Tissues via Metal Nanoparticle Labeling

Chemical probes are key components of the bioimaging toolbox, as they label biomolecules in cells and tissues. The new challenge in bioimaging is to design chemical probes for three-dimensional (3D) tissue imaging. In this work, we discovered that light scattering of metal nanoparticles can provide 3D imaging contrast in intact and transparent tissues. The nanoparticles can act as a template for the chemical growth of a metal layer to further enhance the scattering signal. The use of chemically grown nanoparticles in whole tissues can amplify the scattering to produce a 1.4 million-fold greater photon yield than obtained using common fluorophores. These probes are non-photobleaching and can be used alongside fluorophores without interference. We demonstrated three distinct biomedical applications: (a) molecular imaging of blood vessels, (b) tracking of nanodrug carriers in tumors, and (c) mapping of lesions and immune cells in a multiple sclerosis mouse model. Our strategy establishes a distinct yet complementary set of imaging probes for understanding disease mechanisms in three dimensions

Three-Dimensional Imaging of Transparent Tissues via Metal Nanoparticle Labeling

Chemical probes are key components of the bioimaging toolbox, as they label biomolecules in cells and tissues. The new challenge in bioimaging is to design chemical probes for three-dimensional (3D) tissue imaging. In this work, we discovered that light scattering of metal nanoparticles can provide 3D imaging contrast in intact and transparent tissues. The nanoparticles can act as a template for the chemical growth of a metal layer to further enhance the scattering signal. The use of chemically grown nanoparticles in whole tissues can amplify the scattering to produce a 1.4 million-fold greater photon yield than obtained using common fluorophores. These probes are non-photobleaching and can be used alongside fluorophores without interference. We demonstrated three distinct biomedical applications: (a) molecular imaging of blood vessels, (b) tracking of nanodrug carriers in tumors, and (c) mapping of lesions and immune cells in a multiple sclerosis mouse model. Our strategy establishes a distinct yet complementary set of imaging probes for understanding disease mechanisms in three dimensions