Darren Magda
University of California, Berkeley
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Darren Magda.
Chemical Communications | 2015
Darpan N. Pandya; Sylvie Pailloux; David Tatum; Darren Magda; Thaddeus J. Wadas
The development of bifunctional chelators (BFCs) which can stably chelate zirconium-89 ((89)Zr) while being conjugated to targeting molecules is an area of active research. Herein we report the first octadentate terephthalamide ligands, which are easily radiolabeled with (89)Zr and are highly stable in vitro. They represent a novel class of chelators, which are worthy of further development as BFCs for (89)Zr.
Theranostics | 2016
Jeff N. Tinianow; Darpan N. Pandya; Sylvie Pailloux; Annie Ogasawara; Alexander N. Vanderbilt; Herman S. Gill; Simon Williams; Thaddeus J. Wadas; Darren Magda; Jan Marik
A novel octadentate 3-hydroxypyridin-2-one (2,3-HOPO) based di-macrocyclic ligand was evaluated for chelation of 89Zr; subsequently, it was used as a bi-functional chelator for preparation of 89Zr-labeled antibodies. Quantitative chelation of 89Zr4+ with the octadentate ligand forming 89ZrL complex was achieved under mild conditions within 15 minutes. The 89Zr-complex was stable in vitro in presence of DTPA, but a slow degradation was observed in serum. In vivo, the hydrophilic 89Zr-complex showed prevalently renal excretion; and an elevated bone uptake of radioactivity suggested a partial release of 89Zr4+ from the complex. The 2,3-HOPO based ligand was conjugated to the monoclonal antibodies, HER2-specific trastuzumab and an isotypic anti-gD antibody, using a p-phenylene bis-isothiocyanate linker to yield products with an average loading of less than 2 chelates per antibody. Conjugated antibodies were labeled with 89Zr under mild conditions providing the PET tracers in 60-69% yield. Despite the limited stability in mouse serum; the PET tracers performed very well in vivo. The PET imaging in mouse model of HER2 positive ovarian carcinoma showed tumor uptake of 89Zr-trastuzumab (29.2 ± 12.9 %ID/g) indistinguishable (p = 0.488) from the uptake of positive control 89Zr-DFO-trastuzumab (26.1 ± 3.3 %ID/g). In conclusion, the newly developed 3-hydroxypyridin-2-one based di-macrocyclic chelator provides a viable alternative to DFO-based heterobifunctional ligands for preparation of 89Zr-labeled monoclonal antibodies for immunoPET studies.
PLOS ONE | 2017
Nikunj Bhatt; Darpan N. Pandya; Jide Xu; David Tatum; Darren Magda; Thaddeus J. Wadas; C. Andrew Boswell
The development of bifunctional chelators (BFCs) for zirconium-89 immuno-PET applications is an area of active research. Herein we report the synthesis and evaluation of octadentate hydroxyisophthalamide ligands (1 and 2) as zirconium-89 chelators. While both radiometal complexes could be prepared quantitatively and with excellent specific activity, preparation of 89Zr-1 required elevated temperature and an increased reaction time. 89Zr-1 was more stable than 89Zr-2 when challenged in vitro by excess DTPA or serum proteins and in vivo during acute biodistribution studies. Differences in radiometal complex stability arise from structural changes between the two ligand systems, and suggest further ligand optimization is necessary to enhance 89Zr chelation.
Chemical Science | 2016
Jonathan Arambula; Rebecca McCall; K. J. Sidoran; Darren Magda; Nicholas Mitchell; Christopher W. Bielawski; Vincent M. Lynch; Jonathan L. Sessler; Kuppuswamy Arumugam
Archive | 2007
Shanthi Adimoolam; Joseph J. Buggy; Darren Magda; Richard A. Miller
Archive | 1995
Jonathan L. Sessler; Anthony Harriman; Richard A. Miller; Tarak D. Mody; Gregory W. Hemmi; Vladimír Král; Darren Magda
Archive | 1997
Darren Magda; Shaun P. Crofts; Meredith Wright
Archive | 1996
Darren Magda; Jonathan L. Sessler
Archive | 2007
Darren Magda; Jonathan L. Sessler
Archive | 2000
Jonathan L. Sessler; Darren Magda