Fe- and Ln-DOTAm-F12 Are Effective Paramagnetic Fluorine Contrast Agents for MRI in Water and Blood.

A series of fluorinated macrocyclic complexes, M-DOTAm-F12, where M is La, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Fe, was synthesized, and their potential as fluorine magnetic resonance imaging (MRI) contrast agents was evaluated. The high water solubility of these complexes and the presence of a single fluorine NMR signal, two necessary parameters for in vivo MRI, are substantial advantages over currently used organic polyfluorocarbons and other reported paramagnetic F probes. Importantly, the sensitivity of the paramagnetic probes on a per fluorine basis is at least 1 order of magnitude higher than that of diamagnetic organic probes.

Effect of lanthanide complex structure on cell viability and association.

A systematic study of the effect of hydrophobicity and charge on the cell viability and cell association of lanthanide metal complexes is presented. The terbium luminescent probes feature a macrocyclic polyaminocarboxylate ligand (DOTA) in which the hydrophobicity of the antenna and that of the carboxyamide pendant arms are independently varied. Three sensitizing antennas were investigated in terms of their function in vitro: 2-methoxyisophthalamide (IAM(OMe)), 2-hydroxyisophthalamide (IAM), and 6-methylphenanthridine (Phen).

A magnetoplasmonic imaging agent for copper(I) with dual response by MRI and dark field microscopy.

We present the design and synthesis of a responsive magnetoplasmonic assembly for copper(I) which allows monitoring of the concentration of the metal both in three dimensions by magnetic resonance imaging and with high spatial resolution by dark field microscopy. The probe consists of azide-functionalized iron oxide nanoparticles 11.6 nm in diameter and acetylene-terminated gold nanoparticles 44 nm in diameter that form three-dimensional networks of intermingled magnetic and plasmonic nanoparticles in the presence of copper.

Magnetoluminescent light switches--dual modality in DNA detection.

The synthesis and properties of two responsive magnetoluminescent iron oxide nanoparticles for dual detection of DNA by MRI and luminescence spectroscopy are presented. These magnetoluminescent agents consist of iron oxide nanoparticles conjugated with metallointercalators via a polyethylene glycol linker. Two metallointercalators were investigated: Ru(bpy')(phen)(dppz), which turns on upon DNA intercalation, and Eu-DOTA-Phen, which turns off.

A selective luminescent probe for the direct time-gated detection of adenosine triphosphate.

A molecular probe for the luminescent detection of adenosine nucleotides is presented. The probe, Tb-DOTAm-Phen, readily distinguishes among the three adenosine nucleotides in buffered aqueous conditions at neutral pH, a requirement for the direct monitoring of enzymatic reactions converting adenosine triphosphate (ATP) to adenosine diphosphate or adenosine monophosphate. The probe is most efficient under millimolar concentrations of ATP which are relevant to intracellular conditions.

A ratiometric probe for the selective time-gated luminescence detection of potassium in water.

A europium probe for the ratiometric detection of potassium in water is presented. This probe demonstrates high sensitivity, with an affinity for K(+) in the mM range, and high selectivity for K(+) over Na(+), Ca(2+), Mg(2+) and Li(+). The long luminescence lifetime of the probe and its large Stokes shift further enable accurate determination of the concentration of K(+) in complex aqueous media.