Hide menu

Core Research

     The division of Molecular Surface Physics and Nano Science is a new division at Applied Physics IFM, active in the field of Nanomaterial and Biomolecular Surface Physics and Spectroscopy.

1. Nanoparticles for Biomedical Imaging

    1.1. MRI contrast enhancement

    1.2. Luminescent probes

2. Design of Selective Biomolecular Systems

    2.1. Minimum sequence of recognition

    2.2. Neuro-type monolayers

1. Nanoparticles for Biomedical Imaging

 

1.1. MRI contrast agents

In this project we are designing and characterizing rare earth nanoparticles to optimize the contrast in magnetic resonance imaging (MRI). This project includes material design and synthesis, characterization, surface modification, biofunctionalization and signal optimization followed by tagging for targeting purposes. With this new contrast agent the aim is to obtain higher resolution, tissue specific images and cell- and molecular imaging.

The material developed has high potential as a positive MRI contrast agent. We have initiated and established a spin off company Spago Imaging AB , during 2007.

Recent publications:

Highly Water-Dispersible Surface-Modified Gd2O3 Nanoparticles for Potential Dual-Modal Bioimaging: Water-dispersible and luminescent gadolinium oxide (GO) nanoparticles (NPs) were obtained cleverly by using fluorescent small water-soluble conjugated carboxylates (HL) coating. The obtained GO NPs (GO-L) show long-term colloidal stability and intense blue fluorescence. The optical characteristic of particles was further promoted by doping europium(III) component . The europium(III) doped GO-L (Eu:GO-L) gives intense sensitized red luminescence of europium(III) through an antenna effect. The size of the particles was well controlled and by that promising for biomedical application. The average diameter of the GO core in GO-L is about 4 nm, and the hydrodynamic diameters of the monodispersed GO-L in estimated to be ~13 nm. Importantly, effective longitudinal water proton relaxivities of these nanoparticles are higher than those of positive contrast agents based on gadolinium complexes such as Gd-DOTA, which are currently used clinically for clinical magnetic resonance imaging (MRI). In this work, the particles have also been successfully tested in cellular imaging for dual modalities.

Gd2O3 Nanoparticles for MRI Contrast Enhancement: Synthesis and Characterization of PEGylated Gd2O3 Nanoparticles for MRI Contrast Enhancement ... Guided, smart, targeting nanoparticulate magnetic resonance imaging (MRI) contrast agents inducing high MRI signal will be valuable tools for future tissue specific imaging and investigation of molecular and cellular events. ... The aim of this study is to develop and design a contrast agent for MRI examination that is more powerful with respect to both MR signal enhancement and targeting functionality than what is commercially available today. ...

1.2. Luminescent probes

Nanoparticles for luminescent probes in bio-imaging have recently attracted widespread interest in biology and medicine. In comparison with commonly used organic dyes, luminescent nanoparticles are better in terms of photostability and sensitivity. The optical features of luminescent nanoparticles are critical for real time tracking and monitoring of biological events in the cellular level. Nanoparticle probes are also shown highly suitable for immunoassay and other diagnostic and therapeutic applications.

Recent publications:

High-intensity near-IR fluorescence in semiconducting polymer dots achieved by cascade FRET strategy :Near-IR (NIR) emitting semiconducting polymer dots (Pdots) with ultrabright fluorescence have been prepared for specific cellular targeting. A series of π-conjugated polymers were synthesized to form water dispersible multicomponent Pdots by an ultrasonication-assisted co-precipitation method. By optimizing cascade energy transfer in Pdots, high-intensity NIR fluorescence (Φ = 0.32) with tunable excitations, large absorption–emission separation (up to 330 nm), and narrow emission bands (FWHM = 44 nm) have been achieved. Single-particle fluorescence imaging show that the as-prepared NIR Pdots were more than three times brighter than the commercially available Qdot705 with comparable sizes under identical conditions of excitation and detection. Because of the covalent introduction of carboxylic acid groups into polymer side chains, the bioconjugation between NIR-emitting Pdots and streptavidins can be readily completed via these functional groups on the surface of Pdots. Furthermore, through flow cytometry and confocal fluorescence microscopy the NIR-emitting Pdot–streptavidin conjugates proved that they could effectively label EpCAM receptors on the surface of MCF-7 cells, via specific binding between streptavidin and biotin.

Temperature-Controlled Guest Encapsulation and Light Harvesting: We report the self-assembly of stable nanoscale coordination polymers (NCPs), which exhibit temperature-controlled guest encapsulation and release, as well as an efficient light-harvesting property. NCPs are obtained by coordination-directed organization ...

Biotinylation of ZnO Nanoparticles and Thin Films: This study reports ZnO nanoparticles and thin film surface modification using a two-step functionalization strategy. A small silane molecule was used to build up a stabilizing layer and for conjugation of biotin (vitamin B7), as a specific tag. Biotin was ...

2. Design of Selective Biomolecular Systems

2.1. Minimum sequence of recognition

 

Recent Publications:

α2A-Adrenergic Receptor Derived Peptide Adsorbates: The affinity of α2A-adrenergic receptor (α2A-AR) derived peptide adsorbates for the functional bovine brain G-protein is studied in the search for the minimum sequence recognition. Three short peptides (GPR-i2c, GPR-i3n, and GPR-i3c) are designed to mimic ...

2.2. Neuro-type monolayers

Neurotransmitter inspired molecular systems are designed, synthesized and evaluated by means of molecular orientation, binding strength to substrate, packing density etc. Our focus now is on the principles of coordination of signal substances, selectivity processes and biorecognition. Platform used is self assembly and thiol chemistry followed by stepwise coupling sequences .  

Recent Publications:

Noradrenaline and a Thiol Analogue on Gold Surfaces: Self-assembled monolayers and multilayers of a noradrenaline analogue (Nor-Pt) on gold substrates as well as multilayers of noradrenaline have been investigated by means of the molecular orientation, the molecule−surface interaction, the molecular composition and the functional group availability for further biointeraction processes, using X-ray photoelectron spectroscopy (XPS), infrared reflection−absorption spectroscopy (IRAS), and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy......


Responsible for this page: Kajsa Uvdal
Last updated: 12/18/13