John F. Valliant

Bio: John F. Valliant is an academic researcher from McMaster University. The author has contributed to research in topics: Carborane & Biodistribution. The author has an hindex of 33, co-authored 162 publications receiving 4579 citations. Previous affiliations of John F. Valliant include Lawson Health Research Institute & University of Guelph.

The bioinorganic and medicinal chemistry of carboranes: from new drug discovery to molecular imaging and therapy

Abstract: The role of carboranes in medicinal chemistry has diversified in recent years and now extends into areas of drug discovery, molecular imaging, and targeted radionuclide therapy. An introduction to carborane chemistry is provided to familiarize the non-expert with some key properties of these molecules, followed by an overview of current medicinally-orientated research involving carboranes. The broad-ranging nature of this research is illustrated, with emphasis placed on recent highlights and advances in this field.

Technetium and gallium derived radiopharmaceuticals: comparing and contrasting the chemistry of two important radiometals for the molecular imaging era.

Abstract: ment of therapies, allows for selection of the most potent interventions, and is a way to assess early on during therapy * Corresponding authors: (J.F.V.) E-mail: valliant@mcmaster.ca. Fax: 905522-7776. Tel.: 905-525-9140 ext. 22840. (J.Z.) E-mail: jazubiet@syr.edu. Fax: 315-443-4070. Tel.: 315-443-2547. † Syracuse University. ‡ McMaster University. § Current address: Children’s Hospital Boston, Division of Nuclear Medicine, Department of Radiology, 300 Longwood Avenue, Boston, MA 02115. Mark Daniel Bartholomä was born in Neunkirchen (Germany) and received his diploma (2002) and his doctoral degree (2007) from the Saarland University in Saarbrücken (Germany) under the supervision of Prof. Kaspar Hegetschweiler on the synthesis and complex formation of multidentate derivatives of 1,3,5-triamino-1,3,5-trideoxy-cis-inositol. After a postdoctoral appointment in Prof. Jon Zubieta’s research group at Syracuse University working on Re/Tc conjugated nucleoside analogues for noninvasive imaging from 2007 to 2009, he joined Prof. Alan Packard’s group in 2010 at Harvard Medical School to study 18F radiolabeled perfusion tracers. Educated as a coordination chemist, his research interests focus on the development of novel ligand systems and investigation of their corresponding complex formation as well as their biochemical background and medical applications including the development of radiopharmaceuticals.

Bridging the gap between in vitro and in vivo imaging: isostructural Re and 99mTc complexes for correlating fluorescence and radioimaging studies.

Abstract: A bifunctional ligand that is capable of forming Re and 99mTc complexes as complementary fluorescent and radioactive probes was developed. The tridentate bis(quinoline) amine ligand, which is referred to as the SAACQ system, was prepared in a single step from Fmoc protected lysine in high yield. Reaction of the SAACQ ligand with [Re(CO)3Br3]2- resulted in the formation of the SAACQ−(Re(CO)3)+complex which exhibits favorable fluorescence properties including a long lifetime and a large Stoke's shift. Because the SAACQ ligand is derived from an amino acid, it can readily be linked to or incorporated within peptides as a means of targeting the probe to specific receptors. To demonstrate this feature, the SAACQ ligand and the SAACQ−Re complex were incorporated into fMLFG, a peptide that binds to the formyl peptide receptor (FPR). Uptake of the fMLF[(SAACQ−Re(CO)3)+]G conjugate into human leukocytes in vitro was visualized by fluorescence microscopy, and the observed distribution of the peptide was similar to ...

Phosphorescent heavy-metal complexes for bioimaging

Abstract: The application of phosphorescent heavy-metal complexes with d6, d8 and d10 electron configurations for bioimaging is a new and promising research field and has been attracting increasing interest. In this critical review, we systematically evaluate the advantages of phosphorescent heavy-metal complexes as bioimaging probes, including their photophysical properties, cytotoxicity and cellular uptake mechanisms. The progress of research into the use of phosphorescent heavy-metal complexes for staining different compartments of cells, monitoring intracellular functional species, providing targeted bioimaging, two-photon bioimaging, small-animal bioimaging, multimodal bioimaging and time-resolved bioimaging is summarized. In addition, several possible future directions in this field are also discussed (133 references).