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Kuda-Wedagedara ANW, Allen MJ. Enhancing magnetic resonance imaging with contrast agents for ultra-high field strengths. Analyst 2015; 139:4401-10. [PMID: 25054827 DOI: 10.1039/c4an00990h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Contrast agents are diagnostic tools that often complement magnetic resonance imaging. At ultra-high field strengths (≥7 T), magnetic resonance imaging is capable of generating desirable high signal-to-noise ratios, but clinically available contrast agents are less effective at ultra-high field strengths relative to lower fields. This gap in effectiveness demands the development of contrast agents for ultra-high field strengths. In this minireview, we summarize contrast agents reported during the last three years that focused on ultra-high field strengths.
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Banerjee SR, Ngen EJ, Rotz MW, Kakkad S, Lisok A, Pracitto R, Pullambhatla M, Chen Z, Shah T, Artemov D, Meade TJ, Bhujwalla ZM, Pomper MG. Synthesis and Evaluation of GdIII-Based Magnetic Resonance Contrast Agents for Molecular Imaging of Prostate-Specific Membrane Antigen. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201503417] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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53
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Banerjee SR, Ngen EJ, Rotz MW, Kakkad S, Lisok A, Pracitto R, Pullambhatla M, Chen Z, Shah T, Artemov D, Meade TJ, Bhujwalla ZM, Pomper MG. Synthesis and Evaluation of Gd(III) -Based Magnetic Resonance Contrast Agents for Molecular Imaging of Prostate-Specific Membrane Antigen. Angew Chem Int Ed Engl 2015. [PMID: 26212031 DOI: 10.1002/anie.201503417] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Magnetic resonance (MR) imaging is advantageous because it concurrently provides anatomic, functional, and molecular information. MR molecular imaging can combine the high spatial resolution of this established clinical modality with molecular profiling in vivo. However, as a result of the intrinsically low sensitivity of MR imaging, high local concentrations of biological targets are required to generate discernable MR contrast. We hypothesize that the prostate-specific membrane antigen (PSMA), an attractive target for imaging and therapy of prostate cancer, could serve as a suitable biomarker for MR-based molecular imaging. We have synthesized three new high-affinity, low-molecular-weight Gd(III) -based PSMA-targeted contrast agents containing one to three Gd(III) chelates per molecule. We evaluated the relaxometric properties of these agents in solution, in prostate cancer cells, and in an in vivo experimental model to demonstrate the feasibility of PSMA-based MR molecular imaging.
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Affiliation(s)
- Sangeeta Ray Banerjee
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA).
| | - Ethel J Ngen
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Matthew W Rotz
- Chemistry, Northwestern University, Evanston, IL 60208 (USA)
| | - Samata Kakkad
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Ala Lisok
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Richard Pracitto
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Mrudula Pullambhatla
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Zhengping Chen
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Tariq Shah
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Dmitri Artemov
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Thomas J Meade
- Chemistry, Northwestern University, Evanston, IL 60208 (USA)
| | - Zaver M Bhujwalla
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
| | - Martin G Pomper
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21231 (USA)
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Wu Y, Hao G, Ramezani S, Saha D, Zhao D, Sun X, Sherry AD. [(68) Ga]-HP-DO3A-nitroimidazole: a promising agent for PET detection of tumor hypoxia. CONTRAST MEDIA & MOLECULAR IMAGING 2015; 10:465-72. [PMID: 26122548 DOI: 10.1002/cmmi.1649] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 04/14/2015] [Accepted: 05/18/2015] [Indexed: 12/17/2022]
Abstract
The goal of this study is to evaluate a new (68) Ga-based imaging agent for detecting tumor hypoxia using positron emission tomography (PET). The new hypoxia targeting agent reported here, [(68) Ga]-HP-DO3A-nitroimidazole ([(68) Ga]-HP-DO3A-NI), was constructed by linking a nitroimidazole moiety with the macrocyclic ligand component of ProHance®, HP-DO3A. The hypoxia targeting capability of this agent was evaluated in A549 lung cancer cells in vitro and in SCID mice bearing subcutaneous A549 tumor xenografts. The cellular uptake assays showed that significantly more [(68) Ga]-HP-DO3A-NI accumulates in hypoxic tumor cells at 30, 60 and 120 min than in the same cells exposed to 21% O2 . The agent also accumulated in hypoxic tumors in vivo to give a tumor/muscle ratio (T/M) of 5.0 ± 1.2 (n = 3) as measured by PET at 2 h post-injection (p.i.). This was further confirmed by ex vivo biodistribution data. In addition, [(68) Ga]-HP-DO3A-NI displayed very favorable pharmacokinetic properties, as it was cleared largely through the kidneys with little to no accumulation in liver, heart or lung (%ID/g < 0.5%) at 2 h p.i. The specificity of the agent for hypoxic tissues was further validated in a comparative study with a control compound, [(68) Ga]-HP-DO3A, which lacks the nitroimidazole moiety, and by PET imaging of tumor-bearing mice breathing air versus 100% O2 . Given the commercial availability of cGMP (68) Ge/(68) Ga generators and the ease of (68) Ga labeling, the new agent could potentially be widely applied for imaging tumor hypoxia prior to radiation therapy.
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Affiliation(s)
- Yunkou Wu
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Deparatment of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Guiyang Hao
- Deparatment of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Saleh Ramezani
- Deparatment of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Debabrata Saha
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Dawen Zhao
- Deparatment of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Xiankai Sun
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Deparatment of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - A Dean Sherry
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Deparatment of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Chemistry, University of Texas at Dallas, Richardson, TX, 75080, USA
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55
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Harrison VSR, Carney CE, Macrenaris KW, Meade TJ. A multimeric MR-optical contrast agent for multimodal imaging. Chem Commun (Camb) 2015; 50:11469-71. [PMID: 25137290 DOI: 10.1039/c4cc05651e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We describe the design, synthesis and in vitro evaluation of a multimodal and multimeric contrast agent. The agent consists of three macrocyclic Gd(III) chelates conjugated to a fluorophore and possesses high relaxivity, water solubility, and is nontoxic. The modular synthesis is amenable for the incorporation of a variety of fluorophores to generate molecular constructs for a number of applications.
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Affiliation(s)
- Victoria S R Harrison
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA.
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Rotz MW, Culver KSB, Parigi G, MacRenaris KW, Luchinat C, Odom TW, Meade TJ. High relaxivity Gd(III)-DNA gold nanostars: investigation of shape effects on proton relaxation. ACS NANO 2015; 9:3385-96. [PMID: 25723190 PMCID: PMC4489565 DOI: 10.1021/nn5070953] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Gadolinium(III) nanoconjugate contrast agents (CAs) have distinct advantages over their small-molecule counterparts in magnetic resonance imaging. In addition to increased Gd(III) payload, a significant improvement in proton relaxation efficiency, or relaxivity (r1), is often observed. In this work, we describe the synthesis and characterization of a nanoconjugate CA created by covalent attachment of Gd(III) to thiolated DNA (Gd(III)-DNA), followed by surface conjugation onto gold nanostars (DNA-Gd@stars). These conjugates exhibit remarkable r1 with values up to 98 mM(-1) s(-1). Additionally, DNA-Gd@stars show efficient Gd(III) delivery and biocompatibility in vitro and generate significant contrast enhancement when imaged at 7 T. Using nuclear magnetic relaxation dispersion analysis, we attribute the high performance of the DNA-Gd@stars to an increased contribution of second-sphere relaxivity compared to that of spherical CA equivalents (DNA-Gd@spheres). Importantly, the surface of the gold nanostar contains Gd(III)-DNA in regions of positive, negative, and neutral curvature. We hypothesize that the proton relaxation enhancement observed results from the presence of a unique hydrophilic environment produced by Gd(III)-DNA in these regions, which allows second-sphere water molecules to remain adjacent to Gd(III) ions for up to 10 times longer than diffusion. These results establish that particle shape and second-sphere relaxivity are important considerations in the design of Gd(III) nanoconjugate CAs.
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Affiliation(s)
- Matthew W. Rotz
- Departments of Chemistry, Molecular Biosciences, Neurobiology, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Kayla S. B. Culver
- Departments of Chemistry, Materials Science and Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Keith W. MacRenaris
- Quantitative Bio-elemental Imaging Center, Department of Molecular Biosciences, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Teri W. Odom
- Departments of Chemistry, Materials Science and Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Thomas J. Meade
- Departments of Chemistry, Molecular Biosciences, Neurobiology, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
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58
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Boros E, Caravan. P. Probing the structure-relaxivity relationship of bis-hydrated Gd(DOTAla) derivatives. Inorg Chem 2015; 54:2403-10. [PMID: 25693053 PMCID: PMC4758459 DOI: 10.1021/ic503035f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two structural isomers of the heptadentate chelator DO3Ala were synthesized, with carboxymethyl groups at either the 1,4- or 1,7-positions of the cyclen macrocycle. To interrogate the relaxivity under different rotatational dynamics regimes, the pendant primary amine was coupled to ibuprofen to enable binding to serum albumin. These chelators 6a and 6b form bis(aqua) ternary complexes with Gd(III) or Tb(III) as estimated from relaxivity measurements or luminescence lifetime measurements in water. The relaxivity of [Gd(6a)(H2O)2] and [Gd(6b)(H2O)2] was measured in the presence and absence of coordinating anions prevalent in vivo such as phosphate, lactate, and bicarbonate and compared with data attained for the q = 2 complex [Gd(DO3A)(H2O)2]. We found that relaxivity was reduced through formation of ternary complexes with lactate and bicarbonate, albeit to a lesser degree then the relaxivity of Gd(DO3A). In the presence of 100-fold excess phosphate, relaxivity was slightly increased and typical for q = 2 complexes of this size (8.3 mM(-1) s(-1) and 9.5 mM(-1) s(-1), respectively, at 37 °C, 60 MHz). Relaxivity for the complexes in the presence of HSA corresponded well to relaxivity obtained for complexes with reduced access for inner-sphere water (13.5 and 12.7 mM(-1) s(-1) at 37 °C, 60 MHz). Mean water residency time at 37 °C was determined using temperature-dependent (17)O-T2 measurements at 11.7 T and calculated to be (310)τM = 23 ± 1 ns for both structural isomers. Kinetic inertness under forcing conditions (pH 3, competing DTPA ligand) was found to be comparable to [Gd(DO3A)(H2O)]. Overall, we found that the replacement of one of the acetate arms of DO3A with an amino-propionate arm does not significantly alter the relaxometric and kinetic inertness properties of the corresponding Gd complexes; however, it does provide access to easily functionalizable q = 2 derivatives.
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Affiliation(s)
- Eszter Boros
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Peter Caravan.
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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59
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Fontes A, Karimi S, Helm L, Yulikov M, Ferreira PM, André JP. Dinuclear DOTA-Based GdIIIChelates - Revisiting a Straightforward Strategy for Relaxivity Improvement. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201403159] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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60
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Quici S, Casoni A, Foschi F, Armelao L, Bottaro G, Seraglia R, Bolzati C, Salvarese N, Carpanese D, Rosato A. Folic acid-conjugated europium complexes as luminescent probes for selective targeting of cancer cells. J Med Chem 2015; 58:2003-14. [PMID: 25602505 DOI: 10.1021/jm501945w] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We report the synthesis of three optical probes (Eu(3+)⊂1, Eu(3+)⊂2, and Eu(3+)⊂3) having a luminescent Eu complex (signaling unit) bonded in different positions to folic acid (FA), the folate receptor (FR) targeting unit. The structures of the two regioisomers Eu(3+)⊂1 and Eu(3+)⊂2 were assigned by mass spectrometric experiments. The optical properties and stability of these probes were assessed in phosphate-buffered saline, cell culture medium, rat serum, and cellular lysate, and results indicated that they are chemically and photophysically stable. Cytotoxicity was studied with ovarian cancer cells having high (SKOV-3), intermediate (OVCAR-3), low (IGROV-1), or null (A2780) expression of FRs. The internalized probe, evaluated in SKOV-3, IGROV-1, and A2780 cells, was in the order Eu(3+)⊂2 > Eu(3+)⊂1 > Eu(3+)⊂3. No internalization was observed for A2780 cells. Such results, together with those obtained in competition experiments of FA versus Eu(3+)⊂2 and FA or Eu(3+)⊂2 versus (3)H-FA, indicate that internalization is receptor-mediated and that Eu(3+)⊂2 shows high selectivity and specificity for FR.
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Affiliation(s)
- Silvio Quici
- Istituto di Scienze e Tecnologie Molecolari, Consiglio Nazionale delle Ricerche , Via C. Golgi 19, 20133 Milano, Italy
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61
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Wang L, Zhu X, Tang X, Wu C, Zhou Z, Sun C, Deng SL, Ai H, Gao J. A multiple gadolinium complex decorated fullerene as a highly sensitive T1 contrast agent. Chem Commun (Camb) 2015; 51:4390-3. [DOI: 10.1039/c5cc00285k] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A multiple gadolinium complex decorated fullerene (CGDn) as an enhanced T1 contrast agent was presented.
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Affiliation(s)
- Lirong Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
| | - Xianglong Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
| | - Xingyan Tang
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
| | - Changqiang Wu
- National Engineering Research Centre for Biomaterials
- Sichuan University
- Chengdu 610064
- P. R. China
| | - Zijian Zhou
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
| | - Chengjie Sun
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
| | - Shun-Liu Deng
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
| | - Hua Ai
- National Engineering Research Centre for Biomaterials
- Sichuan University
- Chengdu 610064
- P. R. China
| | - Jinhao Gao
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
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63
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Hung AH, Holbrook RJ, Rotz MW, Glasscock CJ, Mansukhani ND, MacRenaris KW, Manus LM, Duch MC, Dam KT, Hersam MC, Meade TJ. Graphene oxide enhances cellular delivery of hydrophilic small molecules by co-incubation. ACS NANO 2014; 8:10168-77. [PMID: 25226566 PMCID: PMC4212791 DOI: 10.1021/nn502986e] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 09/16/2014] [Indexed: 05/22/2023]
Abstract
The delivery of bioactive molecules into cells has broad applications in biology and medicine. Polymer-modified graphene oxide (GO) has recently emerged as a de facto noncovalent vehicle for hydrophobic drugs. Here, we investigate a different approach using native GO to deliver hydrophilic molecules by co-incubation in culture. GO adsorption and delivery were systematically studied with a library of 15 molecules synthesized with Gd(III) labels to enable quantitation. Amines were revealed to be a key chemical group for adsorption, while delivery was shown to be quantitatively predictable by molecular adsorption, GO sedimentation, and GO size. GO co-incubation was shown to enhance delivery by up to 13-fold and allowed for a 100-fold increase in molecular incubation concentration compared to the alternative of nanoconjugation. When tested in the application of Gd(III) cellular MRI, these advantages led to a nearly 10-fold improvement in sensitivity over the state-of-the-art. GO co-incubation is an effective method of cellular delivery that is easily adoptable by researchers across all fields.
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Affiliation(s)
- Andy H. Hung
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Robert J. Holbrook
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Matthew W. Rotz
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Cameron J. Glasscock
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Nikhita D. Mansukhani
- Department of Materials Science and Engineering and Department of Chemistry, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
| | - Keith W. MacRenaris
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Lisa M. Manus
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Matthew C. Duch
- Department of Materials Science and Engineering and Department of Chemistry, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
| | - Kevin T. Dam
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Mark C. Hersam
- Department of Materials Science and Engineering and Department of Chemistry, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
- Address correspondence to ;
| | - Thomas J. Meade
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
- Address correspondence to ;
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Aydın Tekdaş D, Garifullin R, Şentürk B, Zorlu Y, Gundogdu U, Atalar E, Tekinay AB, Chernonosov AA, Yerli Y, Dumoulin F, Guler MO, Ahsen V, Gürek AG. Design of a Gd-DOTA-Phthalocyanine Conjugate Combining MRI Contrast Imaging and Photosensitization Properties as a Potential Molecular Theranostic. Photochem Photobiol 2014; 90:1376-86. [DOI: 10.1111/php.12332] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 08/06/2014] [Indexed: 12/28/2022]
Affiliation(s)
| | - Ruslan Garifullin
- Institute of Materials Science and Nanotechnology; National Nanotechnology Research Center (UNAM); Bilkent University; Ankara Turkey
| | - Berna Şentürk
- Institute of Materials Science and Nanotechnology; National Nanotechnology Research Center (UNAM); Bilkent University; Ankara Turkey
| | - Yunus Zorlu
- Department of Chemistry; Gebze Institute of Technology; Kocaeli Turkey
| | - Umut Gundogdu
- National Magnetic Resonance Research Center (UMRAM); Bilkent University; Ankara Turkey
| | - Ergin Atalar
- National Magnetic Resonance Research Center (UMRAM); Bilkent University; Ankara Turkey
- Department of Electrical and Electronics Engineering; Bilkent University; Ankara Turkey
| | - Ayse B. Tekinay
- Institute of Materials Science and Nanotechnology; National Nanotechnology Research Center (UNAM); Bilkent University; Ankara Turkey
| | | | - Yusuf Yerli
- Physics Department; Arts and Science Faculty; Yildiz Technical University; Istanbul Turkey
| | - Fabienne Dumoulin
- Department of Chemistry; Gebze Institute of Technology; Kocaeli Turkey
| | - Mustafa O. Guler
- Institute of Materials Science and Nanotechnology; National Nanotechnology Research Center (UNAM); Bilkent University; Ankara Turkey
| | - Vefa Ahsen
- Department of Chemistry; Gebze Institute of Technology; Kocaeli Turkey
| | - Ayşe Gül Gürek
- Department of Chemistry; Gebze Institute of Technology; Kocaeli Turkey
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65
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Designing reactivity-based responsive lanthanide probes for multicolor detection in biological systems. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2013.10.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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66
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Townsend TR, Moyle-Heyrman G, Sukerkar PA, MacRenaris KW, Burdette JE, Meade TJ. Progesterone-targeted magnetic resonance imaging probes. Bioconjug Chem 2014; 25:1428-37. [PMID: 25019183 PMCID: PMC4140536 DOI: 10.1021/bc500265h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Determination of progesterone receptor (PR) status in hormone-dependent diseases is essential in ascertaining disease prognosis and monitoring treatment response. The development of a noninvasive means of monitoring these processes would have significant impact on early detection, cost, repeated measurements, and personalized treatment options. Magnetic resonance imaging (MRI) is widely recognized as a technique that can produce longitudinal studies, and PR-targeted MR probes may address a clinical problem by providing contrast enhancement that reports on PR status without biopsy. Commercially available MR contrast agents are typically delivered via intravenous injection, whereas steroids are administered subcutaneously. Whether the route of delivery is important for tissue accumulation of steroid-modified MRI contrast agents to PR-rich tissues is not known. To address this question, modification of the chemistry linking progesterone with the gadolinium chelate led to MR probes with increased water solubility and lower cellular toxicity and enabled administration through the blood. This attribute came at a cost through lower affinity for PR and decreased ability to cross the cell membrane, and ultimately it did not improve delivery of the PR-targeted MR probe to PR-rich tissues or tumors in vivo. Overall, these studies are important, as they demonstrate that targeted contrast agents require optimization of delivery and receptor binding of the steroid and the gadolinium chelate for optimal translation in vivo.
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Affiliation(s)
- Taryn R Townsend
- Departments of Chemistry, Molecular Biosciences, Neurobiology, and Radiology, Northwestern University , Evanston, Illinois 60208, United States
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67
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Preslar AT, Parigi G, McClendon MT, Sefick SS, Moyer TJ, Haney CR, Waters EA, MacRenaris KW, Luchinat C, Stupp SI, Meade TJ. Gd(III)-labeled peptide nanofibers for reporting on biomaterial localization in vivo. ACS NANO 2014; 8:7325-32. [PMID: 24937195 PMCID: PMC4216205 DOI: 10.1021/nn502393u] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 06/17/2014] [Indexed: 05/23/2023]
Abstract
Bioactive supramolecular nanostructures are of great importance in regenerative medicine and the development of novel targeted therapies. In order to use supramolecular chemistry to design such nanostructures, it is extremely important to track their fate in vivo through the use of molecular imaging strategies. Peptide amphiphiles (PAs) are known to generate a wide array of supramolecular nanostructures, and there is extensive literature on their use in areas such as tissue regeneration and therapies for disease. We report here on a series of PA molecules based on the well-established β-sheet amino acid sequence V3A3 conjugated to macrocyclic Gd(III) labels for magnetic resonance imaging (MRI). These conjugates were shown to form cylindrical supramolecular assemblies using cryogenic transmission electron microscopy and small-angle X-ray scattering. Using nuclear magnetic relaxation dispersion analysis, we observed that thermal annealing of the nanostructures led to a decrease in water exchange lifetime (τm) of hundreds of nanoseconds only for molecules that self-assemble into nanofibers of high aspect ratio. We interpret this decrease to indicate more solvent exposure to the paramagnetic moiety on annealing, resulting in faster water exchange within angstroms of the macrocycle. We hypothesize that faster water exchange in the nanofiber-forming PAs arises from the dehydration and increase in packing density on annealing. Two of the self-assembling conjugates were selected for imaging PAs after intramuscular injections of the PA C16V3A3E3-NH2 in the tibialis anterior muscle of a murine model. Needle tracts were clearly discernible with MRI at 4 days postinjection. This work establishes Gd(III) macrocycle-conjugated peptide amphiphiles as effective tracking agents for peptide amphiphile materials in vivo over the timescale of days.
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Affiliation(s)
- Adam T. Preslar
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Mark T. McClendon
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Samantha S. Sefick
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Tyson J. Moyer
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Chad R. Haney
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Emily A. Waters
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Keith W. MacRenaris
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Samuel I. Stupp
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Address correspondence to ,
| | - Thomas J. Meade
- Departments of Chemistry, Materials Science and Engineering, and Institute for BioNanotechnology in Medicine, Chemical and Biological Engineering, Departments of Chemistry, Molecular Biosciences, Neurobiology and Radiology, and Center for Advanced Molecular Imaging, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Address correspondence to ,
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68
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Ye D, Pandit P, Kempen P, Lin J, Xiong L, Sinclair R, Rutt B, Rao J. Redox-triggered self-assembly of gadolinium-based MRI probes for sensing reducing environment. Bioconjug Chem 2014; 25:1526-36. [PMID: 24992373 PMCID: PMC4140571 DOI: 10.1021/bc500254g] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
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Controlled
self-assembly of small molecule gadolinium (Gd) complexes
into nanoparticles (GdNPs) is emerging as an effective approach to
design activatable magnetic resonance imaging (MRI) probes and amplify
the r1 relaxivity. Herein, we employ a
reduction-controlled macrocyclization reaction and self-assembly to
develop a redox activated Gd-based MRI probe for sensing a reducing
environment. Upon disulfide reduction at physiological conditions,
an acyclic contrast agent 1 containing dual Gd-chelates
undergoes intramolecular macrocyclization to form rigid and hydrophobic
macrocycles, which subsequently self-assemble into GdNPs, resulting
in a ∼60% increase in r1 relaxivity
at 0.5 T. Probe 1 has high r1 relaxivity (up to 34.2 mM–1 s–1 per molecule at 0.5 T) upon activation, and also shows a high sensitivity
and specificity for MR detection of thiol-containing biomolecules.
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Affiliation(s)
- Deju Ye
- Molecular Imaging Program, Departments of Radiology and Chemistry, and ‡Department of Materials Science and Engineering, Stanford University , Stanford, California 94305, United States
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69
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Jensen SA, Day ES, Ko CH, Hurley LA, Luciano JP, Kouri FM, Merkel TJ, Luthi AJ, Patel PC, Cutler JI, Daniel WL, Scott AW, Rotz MW, Meade TJ, Giljohann DA, Mirkin CA, Stegh AH. Spherical nucleic acid nanoparticle conjugates as an RNAi-based therapy for glioblastoma. Sci Transl Med 2014; 5:209ra152. [PMID: 24174328 DOI: 10.1126/scitranslmed.3006839] [Citation(s) in RCA: 411] [Impact Index Per Article: 41.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Glioblastoma multiforme (GBM) is a neurologically debilitating disease that culminates in death 14 to 16 months after diagnosis. An incomplete understanding of how cataloged genetic aberrations promote therapy resistance, combined with ineffective drug delivery to the central nervous system, has rendered GBM incurable. Functional genomics efforts have implicated several oncogenes in GBM pathogenesis but have rarely led to the implementation of targeted therapies. This is partly because many "undruggable" oncogenes cannot be targeted by small molecules or antibodies. We preclinically evaluate an RNA interference (RNAi)-based nanomedicine platform, based on spherical nucleic acid (SNA) nanoparticle conjugates, to neutralize oncogene expression in GBM. SNAs consist of gold nanoparticles covalently functionalized with densely packed, highly oriented small interfering RNA duplexes. In the absence of auxiliary transfection strategies or chemical modifications, SNAs efficiently entered primary and transformed glial cells in vitro. In vivo, the SNAs penetrated the blood-brain barrier and blood-tumor barrier to disseminate throughout xenogeneic glioma explants. SNAs targeting the oncoprotein Bcl2Like12 (Bcl2L12)--an effector caspase and p53 inhibitor overexpressed in GBM relative to normal brain and low-grade astrocytomas--were effective in knocking down endogenous Bcl2L12 mRNA and protein levels, and sensitized glioma cells toward therapy-induced apoptosis by enhancing effector caspase and p53 activity. Further, systemically delivered SNAs reduced Bcl2L12 expression in intracerebral GBM, increased intratumoral apoptosis, and reduced tumor burden and progression in xenografted mice, without adverse side effects. Thus, silencing antiapoptotic signaling using SNAs represents a new approach for systemic RNAi therapy for GBM and possibly other lethal malignancies.
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Affiliation(s)
- Samuel A Jensen
- Ken and Ruth Davee Department of Neurology, The Northwestern Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University, 303 East Superior, Chicago, IL 60611, USA
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70
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Wiener EC, Abadjian MC, Sengar R, Vander Elst L, Van
Niekerk C, Grotjahn DB, Leung PY, Schulte C, Moore C, Rheingold AL. Bifunctional chelates optimized for molecular MRI. Inorg Chem 2014; 53:6554-68. [PMID: 24933389 PMCID: PMC4095910 DOI: 10.1021/ic500085g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Indexed: 12/13/2022]
Abstract
Important requirements for exogenous dyes or contrast agents in magnetic resonance imaging (MRI) include an effective concentration of paramagnetic or superparamagnetic ions at the target to be imaged. We report the concise synthesis and characterization of several new enantiopure bifunctional derivatives of (α(1)R,α(4)R,α(7)R,α(10)R)-α(1),α(4),α(7),α(10)-tetramethyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTMA) (and their 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) analogues as controls) that can be covalently attached to a contrast agent delivery system using either click or peptide coupling chemistry. Gd complexes of these derivatives can be attached to delivery systems while maintaining optimal water residence time for increased molecular imaging sensitivity. Long chain biotin (LC-biotin) derivatives of the Eu(III) and Gd(III) chelates associated with avidin are used to demonstrate higher efficiencies. Variable-temperature relaxometry, (17)O NMR, and nuclear magnetic resonance dispersion (NMRD) spectroscopy used on the complexes and biotin-avidin adducts measure the influence of water residence time and rotational correlation time on constrained and unconstrained systems. The Gd(III)-DOTMA derivative has a shorter water residence time than the Gd(III)-DOTA derivative. Compared to the constrained Gd(III)-DOTA derivatives, the rotationally constrained Gd(III)-DOTMA derivative has ∼40% higher relaxivity at 37 °C, which could increase its sensitivity as an MRI agent as well as reduce the dose of the targeting agent.
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Affiliation(s)
- Erik C. Wiener
- Hillman
Cancer Center, University of Pittsburgh
Medical Center, 5117
Centre Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Marie-Caline Abadjian
- Department
of Chemistry and Biochemistry, San Diego
State University, 5500
Campanile Drive, San Diego, California 92182-1030, United States
| | - Raghvendra Sengar
- Hillman
Cancer Center, University of Pittsburgh
Medical Center, 5117
Centre Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Luce Vander Elst
- Department
of General, Organic and Biomedical Chemistry, University of Mons, 7000 Mons, Hainaut, Belgium
| | - Christoffel Van
Niekerk
- Department
of Chemistry and Biochemistry, San Diego
State University, 5500
Campanile Drive, San Diego, California 92182-1030, United States
| | - Douglas B. Grotjahn
- Department
of Chemistry and Biochemistry, San Diego
State University, 5500
Campanile Drive, San Diego, California 92182-1030, United States
| | - Po Yee Leung
- Department
of Chemistry and Biochemistry, San Diego
State University, 5500
Campanile Drive, San Diego, California 92182-1030, United States
| | - Christie Schulte
- Department
of Chemistry and Biochemistry, San Diego
State University, 5500
Campanile Drive, San Diego, California 92182-1030, United States
| | - Curtis
E. Moore
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0385, United States
| | - Arnold L. Rheingold
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0385, United States
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71
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Lasoroski A, Vuilleumier R, Pollet R. Vibrational dynamics of zero-field-splitting hamiltonian in gadolinium-based MRI contrast agents from ab initio molecular dynamics. J Chem Phys 2014; 141:014201. [DOI: 10.1063/1.4885848] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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72
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Boros E, Karimi S, Kenton N, Helm L, Caravan P. Gd(DOTAlaP): exploring the boundaries of fast water exchange in gadolinium-based magnetic resonance imaging contrast agents. Inorg Chem 2014; 53:6985-94. [PMID: 24922178 PMCID: PMC4095929 DOI: 10.1021/ic5008928] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
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Here,
we describe the synthesis of the single amino acid chelator DOTAlaP
and four of its derivatives. The corresponding gadolinium(III) complexes
were investigated for their kinetic inertness, relaxometric properties
at a range of fields and temperatures, water exchange rate, and interaction
with human serum albumin (HSA). Derivatives with one inner-sphere
water (q = 1) were determined to have a mean water
residency time between 8 and 6 ns in phoshate-buffered saline at 37
°C. The corresponding europium complexes were also formed and
used to obtain information on the hydration number of the corresponding
coordination complexes. Two complexes capable of binding HSA were
also synthesized, of which one, Gd(5b), contains no inner-sphere
water, while the other derivative, Gd(4b), is a mixture
of ca. 15% q =1 and 85% q = 0. In
the presence of HSA, the latter displayed a very short mean water
residency time (τM310 = 2.4 ns) and enhanced
relaxivity at intermediate and high fields. The kinetic inertness
of Gd(4b) with respect to complex dissociation was decreased
compared to its DOTAla analogue but still 100-fold more inert than
[Gd(BOPTA)(H2O)]2–. Magnetic resonance
imaging in mice showed that Gd(4b) was able to provide
38% better vessel to muscle contrast compared to the clinically used
HSA binding agent MS-325. Converting one
of the acetate groups in the single amino acid chelator DOTAla to
methylenephosphonate (DOTAlaP) results in gadolinium(III) complexes
with extremely fast water exchange kinetics and/or in equilibrium
between monoaquated (q = 1) and unaquated (q = 0) states. The presence of phosphonate and the very
fast water exchange kinetics result in stable complexes with high
relaxivity at high magnetic fields, especially when bound to serum
albumin.
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Affiliation(s)
- Eszter Boros
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School , 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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73
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Carney CE, MacRenaris KW, Mastarone DJ, Kasjanski DR, Hung AH, Meade TJ. Cell labeling via membrane-anchored lipophilic MR contrast agents. Bioconjug Chem 2014; 25:945-54. [PMID: 24787689 PMCID: PMC4033656 DOI: 10.1021/bc500083t] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
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Cell tracking in vivo with MR imaging requires
the development of contrast agents with increased sensitivity that
effectively label and are retained by cells. Most
clinically approved Gd(III)-based contrast agents require high incubation
concentrations and prolonged incubation times for cellular internalization.
Strategies to increase contrast agent permeability have included conjugating
Gd(III) complexes to cell penetrating peptides, nanoparticles, and
small molecules which have greatly improved cell labeling but have
not resulted in improved cellular retention. To overcome these challenges,
we have synthesized a series of lipophilic Gd(III)-based MR contrast
agents that label cell membranes in vitro. Two of
the agents were synthesized with a multiplexing strategy to contain
three Gd(III) chelates (1 and 2) while the
third contains a single Gd(III) chelate (3). These new
agents exhibit significantly enhanced labeling and retention in HeLa
and MDA-MB-231-mcherry cells compared to agents that are internalized
by cells (4 and Prohance).
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Affiliation(s)
- Christiane E Carney
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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74
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Affiliation(s)
- Marie C. Heffern
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Lauren M. Matosziuk
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Thomas J. Meade
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
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75
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Bottaro G, Rizzo F, Cavazzini M, Armelao L, Quici S. Efficient Luminescence from Fluorene- and Spirobifluorene-Based Lanthanide Complexes upon Near-Visible Irradiation. Chemistry 2014; 20:4598-607. [DOI: 10.1002/chem.201305029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 02/07/2014] [Indexed: 01/05/2023]
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76
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Li Y, Qian Y, Liu T, Zhang G, Hu J, Liu S. Asymmetrically functionalized β-cyclodextrin-based star copolymers for integrated gene delivery and magnetic resonance imaging contrast enhancement. Polym Chem 2014. [DOI: 10.1039/c3py01278f] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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77
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Hung AH, Liang T, Sukerkar PA, Meade TJ. High dynamic range processing for magnetic resonance imaging. PLoS One 2013; 8:e77883. [PMID: 24250788 PMCID: PMC3826760 DOI: 10.1371/journal.pone.0077883] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 09/13/2013] [Indexed: 01/18/2023] Open
Abstract
Purpose To minimize feature loss in T1- and T2-weighted MRI by merging multiple MR images acquired at different TR and TE to generate an image with increased dynamic range. Materials and Methods High Dynamic Range (HDR) processing techniques from the field of photography were applied to a series of acquired MR images. Specifically, a method to parameterize the algorithm for MRI data was developed and tested. T1- and T2-weighted images of a number of contrast agent phantoms and a live mouse were acquired with varying TR and TE parameters. The images were computationally merged to produce HDR-MR images. All acquisitions were performed on a 7.05 T Bruker PharmaScan with a multi-echo spin echo pulse sequence. Results HDR-MRI delineated bright and dark features that were either saturated or indistinguishable from background in standard T1- and T2-weighted MRI. The increased dynamic range preserved intensity gradation over a larger range of T1 and T2 in phantoms and revealed more anatomical features in vivo. Conclusions We have developed and tested a method to apply HDR processing to MR images. The increased dynamic range of HDR-MR images as compared to standard T1- and T2-weighted images minimizes feature loss caused by magnetization recovery or low SNR.
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Affiliation(s)
- Andy H Hung
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois, United States of America
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78
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Matosziuk LM, Leibowitz JH, Heffern MC, MacRenaris KW, Ratner MA, Meade TJ. Structural optimization of Zn(II)-activated magnetic resonance imaging probes. Inorg Chem 2013; 52:12250-61. [PMID: 23777423 PMCID: PMC3805786 DOI: 10.1021/ic400681j] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We report the structural optimization and mechanistic investigation of a series of bioactivated magnetic resonance imaging contrast agents that transform from low relaxivity to high relaxivity in the presence of Zn(II). The change in relaxivity results from a structural transformation of the complex that alters the coordination environment about the Gd(III) center. Here, we have performed a series of systematic modifications to determine the structure that provides the optimal change in relaxivity in response to the presence of Zn(II). Relaxivity measurements in the presence and absence of Zn(II) were used in conjunction with measurements regarding water access (namely, number of water molecules bound) to the Gd(III) center and temperature-dependent (13)C NMR spectroscopy to determine how the coordination environment about the Gd(III) center is affected by the distance between the Zn(II)-binding domain and the Gd(III) chelate, the number of functional groups on the Zn(II)-binding domain, and the presence of Zn(II). The results of this study provide valuable insight into the design principles for future bioactivated magnetic resonance probes.
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Affiliation(s)
- Lauren M. Matosziuk
- Departments of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Jonathan H. Leibowitz
- Departments of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Marie C. Heffern
- Departments of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Keith W. MacRenaris
- Departments of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Mark A. Ratner
- Department of Chemistry, and Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208-3113
| | - Thomas J. Meade
- Departments of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
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79
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Thorsen F, Fite B, Mahakian LM, Seo JW, Qin S, Harrison V, Johnson S, Ingham E, Caskey C, Sundstrøm T, Meade TJ, Harter PN, Skaftnesmo KO, Ferrara KW. Multimodal imaging enables early detection and characterization of changes in tumor permeability of brain metastases. J Control Release 2013; 172:812-22. [PMID: 24161382 DOI: 10.1016/j.jconrel.2013.10.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/14/2013] [Accepted: 10/15/2013] [Indexed: 12/31/2022]
Abstract
Our goal was to develop strategies to quantify the accumulation of model therapeutics in small brain metastases using multimodal imaging, in order to enhance the potential for successful treatment. Human melanoma cells were injected into the left cardiac ventricle of immunodeficient mice. Bioluminescent, MR and PET imaging were applied to evaluate the limits of detection and potential for contrast agent extravasation in small brain metastases. A pharmacokinetic model was applied to estimate vascular permeability. Bioluminescent imaging after injecting d-luciferin (molecular weight (MW) 320 D) suggested that tumor cell extravasation had already occurred at week 1, which was confirmed by histology. 7T T1w MRI at week 4 was able to detect non-leaky 100 μm sized lesions and leaky tumors with diameters down to 200 μm after contrast injection at week 5. PET imaging showed that (18)F-FLT (MW 244 Da) accumulated in the brain at week 4. Gadolinium-based MRI tracers (MW 559 Da and 2.066 kDa) extravasated after 5 weeks (tumor diameter 600 μm), and the lower MW agent cleared more rapidly from the tumor (mean apparent permeabilities 2.27 × 10(-5)cm/s versus 1.12 × 10(-5)cm/s). PET imaging further demonstrated tumor permeability to (64)Cu-BSA (MW 65.55 kDa) at week 6 (tumor diameter 700 μm). In conclusion, high field T1w MRI without contrast may improve the detection limit of small brain metastases, allowing for earlier diagnosis of patients, although the smallest lesions detected with T1w MRI were permeable only to d-luciferin and the amphipathic small molecule (18)F-FLT. Different-sized MR and PET contrast agents demonstrated the gradual increase in leakiness of the blood tumor barrier during metastatic progression, which could guide clinicians in choosing tailored treatment strategies.
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Affiliation(s)
- Frits Thorsen
- Department of Biomedicine, University of Bergen, Bergen, Norway.
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80
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Kotková Z, Helm L, Kotek J, Hermann P, Lukeš I. Gadolinium complexes of monophosphinic acid DOTA derivatives conjugated to cyclodextrin scaffolds: efficient MRI contrast agents for higher magnetic fields. Dalton Trans 2013; 41:13509-19. [PMID: 23018269 DOI: 10.1039/c2dt30858d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Middle-molecular-weight MRI contrast agents based on conjugates of a phosphinic acid DOTA analogue, 1,4,7,10-tetraazacyclododecane-4,7,10-triacetic-1-{methyl[(4-aminophenyl)methyl]phosphinic acid} (DO3AP(ABn)), with amino-substituted cyclodextrins were prepared and studied by a variety of physico-chemical methods. The conjugates were formed by reaction of the corresponding isothiocyanate with per-6-amino-α/β-cyclodextrin and were complexed with the Ln(III) ion to get the final complexes, (LnL)(6)-α-CD and (LnL)(7)-β-CD. Solution structure of the complexes was estimated by investigation of the Eu(III) complexes. The Gd(III) conjugate complexes are endowed with a short water residence time (τ(M) ∼ 10-15 ns at 298 K) and a high abundance of the twisted-square antiprismatic diastereoisomer. They show a high (1)H relaxivity at high fields due to a convenient combination of the fast water exchange rate and the slow rate of the molecular tumbling given by their macromolecular nature. The (1)H relaxation enhancements per molecule of a contrast agent (CA) are very high reaching for a larger (GdL)(7)-β-CD conjugate ∼140 s(-1) mM(-1) and ∼100 s(-1) mM(-1) at 25 °C and magnetic fields 1.5 T and 3 T, respectively, which is the highest reported longitudinal relaxivity for kinetically stable contrast agents of an intermediate molecular mass (<10 kDa) with one water molecule in the first coordination sphere.
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Affiliation(s)
- Zuzana Kotková
- Department of Inorganic Chemistry, Charles University in Prague, Hlavova 2030, 128 40 Prague 2, Czech Republic
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81
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Gambino G, De Pinto S, Tei L, Cassino C, Arena F, Gianolio E, Botta M. A new ditopic Gd(III) complex functionalized with an adamantyl moiety as a versatile building block for the preparation of supramolecular assemblies. J Biol Inorg Chem 2013; 19:133-43. [PMID: 24100595 DOI: 10.1007/s00775-013-1050-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 09/24/2013] [Indexed: 10/26/2022]
Abstract
A dimeric GdAAZTA-like complex (AAZTA is 6-amino-6-methylperhydro-1,4-diazepinetetraacetic acid) bearing an adamantyl group (Gd2L1) able to form strong supramolecular adducts with specific hosts such as β-cyclodextrin (β-CD), poly-β-CD, and human serum albumin (HSA) is reported. The relaxometric properties of Gd2L1 were investigated in aqueous solution by measuring the (1)H relaxivity as a function of pH, temperature, and magnetic field strength. The relaxivity of Gd2L1 (per Gd atom) at 40 MHz and 298 K is 17.6 mM(-1) s(-1), a value that remains almost constant at higher fields owing to the great compactness and rigidity of the bimetallic chelate, resulting in an ideal value for the rotational correlation time for high-field MRI applications (1.5-3.0 T). The noncovalent interaction of Gd2L1 with β-CD, poly-β-CD, and HSA and the relaxometric properties of the resulting host-guest adducts were investigated using (1)H relaxometric methods. Relaxivity enhancements of 29 and 108 % were found for Gd2L1-β-CD and Gd2L1-poly-β-CD, respectively. Binding of Gd2L1 to HSA (KA = 1.2 × 10(4) M(-1)) results in a remarkable relaxivity of 41.4 mM(-1) s(-1) for the bound form (+248 %). The relaxivity is only limited by the local rotation of the complex within the binding site, which decreases on passing from Gd2L1-β-CD to Gd2L1-HSA. Finally, the applicability of Gd2L1 as tumor-targeting agent through passive accumulation of the HSA-bound adduct was evaluated via acquisition of magnetic resonance images at 1 T of B16-tumor-bearing mice. These experiments indicate a considerable signal enhancement (+160 %) in tumor after 60 min from the injection and a very low hepatic accumulation.
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Affiliation(s)
- Giuseppe Gambino
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "Amedeo Avogadro", Viale T. Michel 11, 15121, Alessandria, Italy
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82
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Zhang HW, Wang LQ, Xiang QF, Zhong Q, Chen LM, Xu CX, Xiang XH, Xu B, Meng F, Wan YQ, Deng DYB. Specific lipase-responsive polymer-coated gadolinium nanoparticles for MR imaging of early acute pancreatitis. Biomaterials 2013; 35:356-67. [PMID: 24103651 DOI: 10.1016/j.biomaterials.2013.09.046] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 09/13/2013] [Indexed: 12/13/2022]
Abstract
Currently, available methods for diagnosis of acute pancreatitis (AP) are mainly dependent on serum enzyme analysis and imaging techniques that are too low in sensitivity and specificity to accurately and promptly diagnose AP. The lack of early diagnostic tools highlights the need to search for a highly effective and specific diagnostic method. In this study, we synthesized a conditionally activated, gadolinium-containing, nanoparticle-based MRI nanoprobe as a diagnostic tool for the early identification of AP. Gadolinium diethylenetriaminepentaacetic fatty acid (Gd-DTPA-FA) nanoparticles were synthesized by conjugation of DTPA-FA ligand and gadolinium acetate. Gd-DTPA-FA exhibited low cytotoxicity and excellent biocompatibility when characterized in vitro and in vivo studies. L-arginine induced a gradual increase in the intensity of the T1-weighted MRI signal from 1 h to 36 h in AP rat models. The increase in signal intensity was most significant at 1 h, 6 h and 12 h. These results suggest that the Gd-DTPA-FA as an MRI contrast agent is highly efficient and specific to detect early AP.
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Affiliation(s)
- Hong-Wu Zhang
- Research Center of Translational Medicine, The First Affiliated Hospital, Sun Yat-Sen University, 58# Zhongshan 2nd Road, Guangzhou 510080, China
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83
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Gale EM, Kenton N, Caravan P. [Gd(CyPic3A)(H2O)2]-: a stable, bis(aquated) and high-relaxivity Gd(III) complex. Chem Commun (Camb) 2013; 49:8060-2. [PMID: 23903523 PMCID: PMC3791611 DOI: 10.1039/c3cc44116d] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We report the synthesis and MR relevant properties of CyPic3A, a heptadentate chelator that forms ternary Gd(III) complexes of hydration state q = 2. [Gd(CyPic3A)(H2O)2](-) affords an r1 value of 5.70 mM(-1) s(-1) at 1.41 T and 310 K and displays thermodynamic stability and kinetic inertness comparable to FDA approved MR imaging probes.
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Affiliation(s)
- Eric M Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
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84
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Dynamic aggregation of the mid-sized gadolinium complex {Ph4[Gd(DTTA)(H2O)2]− 3}. J Biol Inorg Chem 2013; 19:145-59. [DOI: 10.1007/s00775-013-1036-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 08/14/2013] [Indexed: 12/28/2022]
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85
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Two multinuclear GdIII macrocyclic complexes as contrast agents with high relaxivity and stability using rigid linkers. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2013.07.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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86
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Hong BJ, Swindell EP, MacRenaris KW, Hankins PL, Chipre AJ, Mastarone DJ, Ahn RW, Meade TJ, O’Halloran TV, Nguyen ST. pH-Responsive Theranostic Polymer-Caged Nanobins (PCNs): Enhanced Cytotoxicity and T1 MRI Contrast by Her2-Targeting. PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION : MEASUREMENT AND DESCRIPTION OF PARTICLE PROPERTIES AND BEHAVIOR IN POWDERS AND OTHER DISPERSE SYSTEMS 2013; 30:770-774. [PMID: 24516291 PMCID: PMC3916701 DOI: 10.1002/ppsc.201300158] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A PCN theranostic platform comprises a doxorubicin (DXR)-loaded liposomal core and an acid-sensitive polymer shell that is functionalized with Herceptin and GdIII-based MRI contrast agents. In vitro testing reveals a 14-fold increase in DXR-based cytotoxicity versus a non-targeted analogue and an 120-fold improvement in cellular GdIII-uptake in comparison with clinically approved DOTA-GdIII, leading to significant T1 MRI contrast enhancement.
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Affiliation(s)
- Bong Jin Hong
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Elden P. Swindell
- Department of Chemical & Biological Engineering, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Keith W. MacRenaris
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Patrick L. Hankins
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Anthony J. Chipre
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Daniel J. Mastarone
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Richard W. Ahn
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Thomas J. Meade
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - Thomas V. O’Halloran
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
| | - SonBinh T. Nguyen
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208-3113 (USA)
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87
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Hung AH, Duch MC, Parigi G, Rotz MW, Manus LM, Mastarone DJ, Dam KT, Gits CC, MacRenaris KW, Luchinat C, Hersam MC, Meade TJ. Mechanisms of Gadographene-Mediated Proton Spin Relaxation. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2013; 117:10.1021/jp406909b. [PMID: 24298299 PMCID: PMC3843495 DOI: 10.1021/jp406909b] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Gd(III) associated with carbon nanomaterials relaxes water proton spins at an effectiveness that approaches or exceeds the theoretical limit for a single bound water molecule. These Gd(III)-labeled materials represent a potential breakthrough in sensitivity for Gd(III)-based contrast agents used for magnetic resonance imaging (MRI). However, their mechanism of action remains unclear. A gadographene library encompassing GdCl3, two different Gd(III)-complexes, graphene oxide (GO), and graphene suspended by two different surfactants and subjected to varying degrees of sonication was prepared and characterized for their relaxometric properties. Gadographene was found to perform comparably to other Gd(III)-carbon nanomaterials; its longitudinal (r1) and transverse (r2) relaxivity is modulated between 12-85 mM-1s-1 and 24-115 mM-1s-1, respectively, depending on the Gd(III)-carbon backbone combination. The unusually large relaxivity and its variance can be understood under the modified Florence model incorporating the Lipari-Szabo approach. Changes in hydration number (q), water residence time (τM), molecular tumbling rate (τR), and local motion (τfast) sufficiently explain most of the measured relaxivities. Furthermore, results implicated the coupling between graphene and Gd(III) as a minor contributor to proton spin relaxation.
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Affiliation(s)
- Andy H. Hung
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Matthew C. Duch
- Department of Materials Science and Engineering and Department of Chemistry, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
| | - Giacomo Parigi
- CERM and Department of Chemistry, University of Florence, via L. Sacconi 6, 50019 Sesto Florence, Italy
| | - Matthew W. Rotz
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Lisa M. Manus
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Daniel J. Mastarone
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Kevin T. Dam
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Colton C. Gits
- Department of Materials Science and Engineering and Department of Chemistry, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
| | - Keith W. MacRenaris
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Claudio Luchinat
- CERM and Department of Chemistry, University of Florence, via L. Sacconi 6, 50019 Sesto Florence, Italy
| | - Mark C. Hersam
- Department of Materials Science and Engineering and Department of Chemistry, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
| | - Thomas J. Meade
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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88
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Zhou Z, Wu X, Kresak A, Griswold M, Lu ZR. Peptide targeted tripod macrocyclic Gd(III) chelates for cancer molecular MRI. Biomaterials 2013; 34:7683-93. [PMID: 23863450 DOI: 10.1016/j.biomaterials.2013.06.057] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 06/26/2013] [Indexed: 02/06/2023]
Abstract
Rational design and develop of targeted contrast agents binding to cancer-related proteins will achieve more accurate cancer diagnosis and prognosis by magnetic resonance (MR) imaging. CREKA is a tumor-homing pentapeptide (Cys-Arg-Glu-Lys-Ala) specifically homes to fibrin-fibronectin complexes abundantly expressed in tumor microenvironment. In this study, we developed and evaluated a CREKA peptide targeted multiplexed Gd-MR probe (CREKA-Tris-Gd(DOTA)3) for MR imaging of breast tumors. CREKA and azide bearing Gd(III) was attached to a maleimide-functional trialkyne scaffold via thiol-maleimide and azide-alkyne click chemistry, respectively. CREKA-Tris-Gd(DOTA)3 has a well-defined structure with a molecular weight of 2914 Da. The T1 relaxivity of CREKA-Tris-Gd(DOTA)3 is 8.06 mM(-1) s(-1) per Gd (24.18 mM(-1) s(-1) per molecule) at room temperature and 3 T. Fluorescence imaging showed high binding specificity of CREKA to a 4T1 breast tumor model in mice while it was not found for the scrambled CREKA (CERAK). The CREKA peptide-targeted contrast agent resulted in greater contrast enhancement than the corresponding CERAK agent and the commercialized contrast agent ProHance(®) in tumor at a dose of 0.1 mmol Gd/kg in female athymic mice bearing 4T1 breast carcinoma xenograft. This small molecular contrast agent was easily excreted from body after imaging indicated low toxicity. The targeted MRI contrast agent has a potential for specific cancer molecular imaging with MRI.
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Affiliation(s)
- Zhuxian Zhou
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
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89
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Luchinat C, Parigi G, Ravera E. Water and Protein Dynamics in Sedimented Systems: A Relaxometric Investigation. Chemphyschem 2013; 14:3156-61. [DOI: 10.1002/cphc.201300167] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Indexed: 11/07/2022]
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90
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Polasek M, Caravan P. Is macrocycle a synonym for kinetic inertness in Gd(III) Complexes? Effect of coordinating and noncoordinating substituents on inertness and relaxivity of Gd(III) chelates with DO3A-like ligands. Inorg Chem 2013; 52:4084-96. [PMID: 23517079 PMCID: PMC3640422 DOI: 10.1021/ic400227k] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Gadolinium chelates with octadentate ligands are widely used as contrast agents for magnetic resonance imaging (MRI), with macrocyclic ligands based on DO3A being preferred for the high kinetic inertness of their Gd chelates. A major challenge in the design of new bifunctional MRI probes is the need to control the rotational motion of the chelate, which greatly affects its relaxivity. In this work we explored facile alkylation of a secondary amine in macrocyclic DO3A-like ligands to create a short, achiral linkage to limit the undesired internal motion of chelates within larger molecular constructs. The acetate moiety on the trans nitrogen was also replaced with either a bidentate (ethoxyacetate, L1 or methyl picolinate, L2) or bulky monodentate (methyl phosphonate, L3) donor arm to give octa- or heptadentate ligands, respectively. The resultant Gd(III) complexes were all monohydrated (q = 1) and exhibited water residency times that spanned 2 orders of magnitude (τM = 2190 ± 170, 3500 ± 90, and 12.7 ± 3.8 ns at 37 °C for GdL1, GdL2, and GdL3, respectively). Alkylation of the secondary amine with a noncoordinating biphenyl moiety resulted in coordinatively saturated q = 0 complexes of octadentate ligands L1 and L2. Relaxivities were limited by slow water exchange and/or lack of water coligand. All complexes showed decreased inertness compared to [Gd(DO3A)] despite higher ligand denticity, and inertness was further decreased upon N-alkylation. These results demonstrate that high kinetic inertness and in vivo safety of Gd chelates with macrocyclic ligands should not be generalized.
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Affiliation(s)
- Miloslav Polasek
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, MA 02129
| | - Peter Caravan
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, MA 02129
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91
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Martín Rodríguez E, Bogdan N, Capobianco JA, Orlandi S, Cavazzini M, Scalera C, Quici S. A highly sensitive luminescent lectin sensor based on an α-d-mannose substituted Tb3+ antenna complex. Dalton Trans 2013; 42:9453-61. [DOI: 10.1039/c3dt33023k] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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92
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Hu J, Liu T, Zhang G, Jin F, Liu S. Synergistically Enhance Magnetic Resonance/Fluorescence Imaging Performance of Responsive Polymeric Nanoparticles Under Mildly Acidic Biological Milieu. Macromol Rapid Commun 2012. [DOI: 10.1002/marc.201200613] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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93
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Boros E, Polasek M, Zhang Z, Caravan P. Gd(DOTAla): a single amino acid Gd-complex as a modular tool for high relaxivity MR contrast agent development. J Am Chem Soc 2012; 134:19858-68. [PMID: 23157602 DOI: 10.1021/ja309187m] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
MR imaging at high magnetic fields benefits from an increased signal-to-noise ratio; however T(1)-based MR contrast agents show decreasing relaxivity (r(1)) at higher fields. High field, high relaxivity contrast agents can be designed by carefully controlling the rotational dynamics of the molecule. To this end, we investigated applications of the alanine analogue of Gd(DOTA), Gd(DOTAla). Fmoc-protected DOTAla suitable for solid phase peptide synthesis was synthesized and integrated into polypeptide structures. Gd(III) coordination results in very rigid attachment of the metal chelate to the peptide backbone through both the amino acid side chain and coordination of the amide carbonyl. Linear and cyclic monomers (GdL1, GdC1), dimers (Gd(2)L2, Gd(2)C2), and trimers (Gd(3)L3, Gd(3)C3) were prepared and relaxivities were determined at different field strengths ranging from 0.47 to 11.7 T. Amide carbonyl coordination was indirectly confirmed by determination of the hydration number q for the EuL1 integrated into a peptide backbone, q = 0.96 ± 0.09. The water residency time of GdL1 at 37 °C was optimal for relaxivity, τ(M) = 17 ± 2 ns. Increased molecular size leads to increased per Gd relaxivity (from r(1) = 7.5 for GdL1 to 12.9 mM(-1) s(-1) for Gd(3)L3 at 1.4 T, 37 °C). The cyclic, multimeric derivatives exhibited slightly higher relaxivities than the corresponding linearized multimers (Gd(2)C2: r(1) = 10.5 mM(-1) s(-1) versus Gd(2)C2-red r(1) = 9 mM(-1) s(-1) at 1.4 T, 37 °C). Overall, all six synthesized Gd complexes had higher relaxivities at low, intermediate, and high fields than the clinically used small molecule contrast agent [Gd(HP-DO3A)(H(2)O)].
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Affiliation(s)
- Eszter Boros
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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94
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Lowell AN, Qiao H, Liu T, Ishikawa T, Zhang H, Oriana S, Wang M, Ricciotti E, FitzGerald GA, Zhou R, Yamakoshi Y. Functionalized low-density lipoprotein nanoparticles for in vivo enhancement of atherosclerosis on magnetic resonance images. Bioconjug Chem 2012; 23:2313-9. [PMID: 23075169 DOI: 10.1021/bc300561e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To allow visualization of macrophage-rich and miniature-sized atheromas by magnetic resonance (MR) imaging, we have converted low-density lipoprotein (LDL) into MR-active nanoparticles via the intercalation of a 1,4,7,10-tetraazacyclodecane-1,4,7-triacetic acid (DO3A) derivative and the subsequent coordination reaction with Gd(3+). After careful removal of nonchelated Gd(3+), an MR-active LDL (Gd(3+)-LDL) with a remarkably high payload of Gd(3+) (in excess of 200 Gd(3+) atoms per particle) and a high relaxivity (r(1) = 20.1 s(-1) mM(-1) per Gd(3+) or 4040 s(-1) mM(-1) per LDL) was obtained. Dynamic light-scattering photon correlation spectroscopy (DLS) and cryo transmission electron microscope (cryoTEM) images showed that Gd(3+)-LDL particles did not aggregate and remained of a similar size (25-30 nm) to native LDL. Intravenous injection of Gd(3+)-LDL into an atherosclerotic mouse model (ApoE(-/-)) resulted in an extremely high enhancement of the atheroma-bearing aortic walls at 48 h after injection. Free Gd(3+) dissociation from Gd(3+)-LDL was not detected over the imaging time window (96 h). Because autologous LDL can be isolated, modified, and returned to the same patient, our results suggest that MR-active LDL can potentially be used as a noninfectious and nonimmunogenic imaging probe for the enhancement of atheroplaques presumably via the uptake into macrophages inside the plaque.
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Affiliation(s)
- Andrew N Lowell
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104-6323, USA
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95
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Mi P, Cabral H, Kokuryo D, Rafi M, Terada Y, Aoki I, Saga T, Takehiko I, Nishiyama N, Kataoka K. Gd-DTPA-loaded polymer-metal complex micelles with high relaxivity for MR cancer imaging. Biomaterials 2012; 34:492-500. [PMID: 23059004 DOI: 10.1016/j.biomaterials.2012.09.030] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 09/16/2012] [Indexed: 11/20/2022]
Abstract
Nanodevices for magnetic resonance imaging of cancer were self-assembled to core-shell micellar structures by metal complex formation of K(2)PtCl(6) with diethylenetriaminepentaacetic acid gadolinium (III) dihydrogen (Gd-DTPA), a T(1)-contrast agent, and poly(ethylene glycol)-b-poly{N-[N'-(2-aminoethyl)-2-aminoethyl]aspartamide} (PEG-b-PAsp(DET)) copolymer in aqueous solution. Gd-DTPA-loaded polymeric micelles (Gd-DTPA/m) showed a hydrodynamic diameter of 45 nm and a core size of 22 nm. Confining Gd-DTPA inside the core of the micelles increased the relaxivity of Gd-DTPA more than 13 times (48 mM(-1) s(-1)). In physiological conditions Gd-DTPA/m sustainedly released Gd-DTPA, while the Pt(IV) complexes remain bound to the polymer. Gd-DTPA/m extended the circulation time in plasma and augmented the tumor accumulation of Gd-DTPA leading to successful contrast enhancement of solid tumors. μ-Synchrotron radiation-X-ray fluorescence results confirmed that Gd-DTPA was delivered to the tumor site by the micelles. Our study provides a facile strategy for incorporating contrast agents, dyes and bioactive molecules into nanodevices for developing safe and efficient drug carriers for clinical application.
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Affiliation(s)
- Peng Mi
- Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
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96
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Santra S, Jativa SD, Kaittanis C, Normand G, Grimm J, Perez JM. Gadolinium-encapsulating iron oxide nanoprobe as activatable NMR/MRI contrast agent. ACS NANO 2012; 6:7281-94. [PMID: 22809405 PMCID: PMC3429787 DOI: 10.1021/nn302393e] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Herein we report a novel gadolinium-encapsulating iron oxide nanoparticle-based activatable NMR/MRI nanoprobe. In our design, Gd-DTPA is encapsulated within the poly(acrylic acid) (PAA) polymer coating of a superparamagnetic iron oxide nanoparticle (IO-PAA), yielding a composite magnetic nanoprobe (IO-PAA-Gd-DTPA) with quenched longitudinal spin-lattice magnetic relaxation (T(1)). Upon release of the Gd-DTPA complex from the nanoprobe's polymeric coating in acidic media, an increase in the T(1) relaxation rate (1/T(1)) of the composite magnetic nanoprobe was observed, indicating a dequenching of the nanoprobe with a corresponding increase in the T(1)-weighted MRI signal. When a folate-conjugated nanoprobe was incubated in HeLa cells, a cancer cell line overexpressing folate receptors, an increase in the 1/T(1) signal was observed. This result suggests that, upon receptor-mediated internalization, the composite magnetic nanoprobe degraded within the cell's lysosome acidic (pH 5.0) environment, resulting in an intracellular release of Gd-DTPA complex with subsequent T(1) activation. In addition, when an anticancer drug (Taxol) was coencapsulated with the Gd-DTPA within the folate receptor targeting composite magnetic nanoprobe, the T(1) activation of the probe coincided with the rate of drug release and corresponding cytotoxic effect in cell culture studies. Taken together, these results suggest that our activatable T(1) nanoagent could be of great importance for the detection of acidic tumors and assessment of drug targeting and release by MRI.
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Affiliation(s)
- Santimukul Santra
- Nanoscience Technology Center and Chemistry Department, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826. USA
| | - Samuel D. Jativa
- Nanoscience Technology Center and Chemistry Department, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826. USA
| | - Charalambos Kaittanis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Guillaume Normand
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Jan Grimm
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - J. Manuel Perez
- Nanoscience Technology Center and Chemistry Department, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826. USA
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97
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Bernard ED, Beking MA, Rajamanickam K, Tsai EC, Derosa MC. Target binding improves relaxivity in aptamer-gadolinium conjugates. J Biol Inorg Chem 2012; 17:1159-75. [PMID: 22903502 DOI: 10.1007/s00775-012-0930-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Accepted: 07/29/2012] [Indexed: 11/24/2022]
Abstract
MRI contrast agents (CA) have been heavily used over the past several decades to enhance the diagnostic value of the obtained images. From a design perspective, two avenues to improve the efficacy of contrast agents are readily evident: optimization of magnetic properties of the CA, and optimization of the pharmacokinetics and distribution of the CA in the patient. Contrast agents consisting of DNA aptamer-gadolinium(III) conjugates provide a single system in which these factors can be addressed simultaneously. In this proof-of-concept study, the 15mer thrombin aptamer was conjugated to diethylenetriaminepentaacetic (DTPA) dianhydride to form a monoamide derivative of the linear open-chain chelate present in the commonly used contrast agent Magnevist(®). The stability of the conjugated DNA aptamer-DTPA-Gd(III) chelate in a transmetallation study using Zn(II) was found to be similar to that reported for DTPA-Gd(III). Relaxivity enhancements of 35 ± 4 and 20 ± 1 % were observed in the presence of thrombin compared to a control protein at fields of 9.4 and 1.5 T, respectively. The inclusion of spacers between the aptamer and the DTPA to eliminate possible steric effects was also investigated but not found to improve the relaxation enhancement achieved in comparison to the unaltered aptamer conjugate.
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Affiliation(s)
- Elyse D Bernard
- Department of Chemistry, Ottawa-Carleton Chemistry Institute, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
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98
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Manus LM, Strauch RC, Hung AH, Eckermann AL, Meade TJ. Analytical methods for characterizing magnetic resonance probes. Anal Chem 2012; 84:6278-87. [PMID: 22624599 PMCID: PMC3418482 DOI: 10.1021/ac300527z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The efficiency of Gd(III) contrast agents in magnetic resonance image enhancement is governed by a set of tunable structural parameters. Understanding and measuring these parameters requires specific analytical techniques. This Feature describes strategies to optimize each of the critical Gd(III) relaxation parameters for molecular imaging applications and the methods employed for their evaluation.
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Affiliation(s)
- Lisa M. Manus
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Renee C. Strauch
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Andy H. Hung
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Amanda L. Eckermann
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
| | - Thomas J. Meade
- Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University, Evanston, Illinois 60208-3113
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99
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Duncan AK, Klemm PJ, Raymond KN, Landry CC. Silica microparticles as a solid support for gadolinium phosphonate magnetic resonance imaging contrast agents. J Am Chem Soc 2012; 134:8046-9. [PMID: 22545921 PMCID: PMC3403734 DOI: 10.1021/ja302183w] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Particle-based magnetic resonance imaging (MRI) contrast agents have been the focus of recent studies, primarily due to the possibility of preparing multimodal particles capable of simultaneously targeting, imaging, and treating specific biological tissues in vivo. In addition, particle-based MRI contrast agents often have greater sensitivity than commercially available, soluble agents due to decreased molecular tumbling rates following surface immobilization, leading to increased relaxivities. Mesoporous silica particles are particularly attractive substrates due to their large internal surface areas. In this study, we immobilized a unique phosphonate-containing ligand onto mesoporous silica particles with a range of pore diameters, pore volumes, and surface areas, and Gd(III) ions were then chelated to the particles. Per-Gd(III) ionic relaxivities ranged from ∼2 to 10 mM(-1) s(-1) (37 °C, 60 MHz), compared to 3.0-3.5 mM(-1) s(-1) for commercial agents. The large surface areas allowed many Gd(III) ions to be chelated, leading to per-particle relaxivities of 3.3 × 10(7) mM(-1) s(-1), which is the largest value measured for a biologically suitable particle.
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Affiliation(s)
- Alexandra K. Duncan
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405, United States
| | - Piper J. Klemm
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Kenneth N. Raymond
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Christopher C. Landry
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405, United States
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100
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Gouin SG, Roger M, Leygue N, Deniaud D, Julienne K, Benoist E, Picard C, Kovensky J, Galaup C. Lanthanide(III) complexes of pyridine–tetraacetic acid-glycoconjugates: Synthesis and luminescence studies of mono and divalent derivatives. Bioorg Med Chem Lett 2012; 22:2684-8. [DOI: 10.1016/j.bmcl.2012.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 03/02/2012] [Accepted: 03/03/2012] [Indexed: 10/28/2022]
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