One way to image the molecular pathology in Alzheimer's disease is by positron emission tomography using probes that target amyloid fibrils. However, these fibrils are not closely linked to the development of the disease. It is now thought that early-stage biomarkers that instigate memory loss are composed of Aβ oligomers.
View Article and Find Full Text PDFAdv Drug Deliv Rev
November 2011
The development of MRI contrast agents has experienced its version of the gilded age over the past decade, thanks largely to the rapid advances in nanotechnology. In addition to progress in single mode contrast agents, which ushered in unprecedented R(1) or R(2) sensitivities, there has also been a boon in the development of agents covering more than one mode of detection. These include T(1)-PET, T(2)-PET T(1)-optical, T(2)-optical, T(1)-T(2) agents and many others.
View Article and Find Full Text PDFNanomaterials with mixed composition, in particular magnetic spinel ferrites, are emerging as efficient contrast agents for magnetic resonance imaging (MRI). Many factors, including size, composition, atomic structure, and surface properties are crucial in the design of such nanoparticle-based probes due to their influence on the magnetic properties. Silica-coated iron oxide (IO-SiO(2)) and cobalt ferrite (CoIO-SiO(2)) nanoparticles were synthesized using standard high temperature thermal decomposition and base-catalyzed water-in-oil microemulsion techniques.
View Article and Find Full Text PDFMost cancers are curable if they are diagnosed and treated at an early stage. Recent studies suggest that nanoarchitectural changes occur within cells during early carcinogenesis and that such changes precede microscopically evident tissue alterations. It follows that the ability to comprehensively interrogate cell nanoarchitecture (e.
View Article and Find Full Text PDFWe report a study of the nanoscale mass-density fluctuations of heterogeneous optical dielectric media, including nanomaterials and biological cells, by quantifying their nanoscale light-localization properties. Transmission electron microscope images of the media are used to construct corresponding effective disordered optical lattices. Light-localization properties are studied by the statistical analysis of the inverse participation ratio (IPR) of the localized eigenfunctions of these optical lattices at the nanoscale.
View Article and Find Full Text PDFMagnetic resonance imaging (MRI) has become a powerful technique in biological molecular imaging and clinical diagnosis. With the rapid progress in nanoscale science and technology, nanostructure-based MR contrast agents are undergoing rapid development. This is in part due to the tuneable magnetic and cellular uptake properties, large surface area for conjugation and favourable biodistribution.
View Article and Find Full Text PDFJ Phys Chem C Nanomater Interfaces
January 2009
Cobalt ferrite magnetic nanostructures were synthesized via a high temperature solution phase method. Spherical nanostructures of various sizes were synthesized with the help of seed mediated growth of the nanostructures in organic phase, while faceted irregular (FI) cobalt ferrite nanostructures were synthesized via the same method but in the presence of a magnetic field. Magnetic properties were characterized by SQUID magnetometry, relaxivity measurements and thermal activation under RF field, as a function of size and shape.
View Article and Find Full Text PDFAn efficient and facile procedure is developed for concurrent in situ synthesis and ordered assembly of metal nanoparticles on a periodic two dimensional protein array. The S-layer protein of Bacillus subtilis exhibiting uniform pore size is used as template. Synthesis of gold and silver nanoparticles anchoring on the pores of S-layer is achieved by chemical reduction of respective metal salt laden protein template.
View Article and Find Full Text PDFPurpose: Colloidal metallic systems have been recently investigated in the area of nanomedicine. Gold nanoparticles have found themselves useful for diagnostic and drug delivery applications. Herein we have reported a novel method for synthesis of gold nanoparticles using a natural, biocompatible and biodegradable polymer; chitosan.
View Article and Find Full Text PDFNanomaterials have gained tremendous importance in biology and medicine because they can be used as carriers for delivering small molecules such as drugs, proteins, and genes. We report herein the binding of the hormone insulin to gold nanoparticles and its application in transmucosal delivery for the therapeutic treatment of diabetes mellitus. Insulin was loaded onto bare gold nanoparticles and aspartic acid-capped gold nanoparticles and delivered in diabetic Wistar rats by both oral and intranasal (transmucosal) routes.
View Article and Find Full Text PDFWe demonstrate the phase transfer of silver nanoparticles synthesized in an aqueous medium into hexane containing the cationic surfactant octadecylamine (ODA). During vigorous shaking of the biphasic mixture, rapid phase transfer of the silver nanoparticles into the organic phase was observed. The phase transfer of the silver nanoparticles arises due to coupling of the silver nanoparticles with the ODA molecules present in organic phase via either coordination bond formation or weak covalent interaction.
View Article and Find Full Text PDFWe demonstrate the synthesis of zirconia nanoparticles in a lipid matrix by a simple, low temperature beaker-based process. This is accomplished by electrostatic entrapment of ZrF6(2-) ions within thermally evaporated octadecylamine (ODA) thin films followed by the low-temperature in situ hydrolysis of the entrapped metal ion complexes. The zirconia particles thus formed were of the monoclinic phase and were fairly monodisperse with particles of average size 40 nm.
View Article and Find Full Text PDF