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Uehara T, Sensui A, Ishioka S, Mizuno Y, Takahashi S, Takemori H, Suzuki H, Arano Y. Manipulating Pharmacokinetics of Purification-Free 99mTc-Labeled Bivalent Probes for In Vivo Imaging of Saturable Targets. Mol Pharm 2020; 17:1621-1628. [PMID: 32275437 DOI: 10.1021/acs.molpharmaceut.0c00070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The accumulation of 99mTc-labeled probes targeting saturable systems of the body is hindered by the presence of a large excess of unlabeled ligands needed to ensure high radiochemical yields in a short reaction time. To address the issue, we recently reported a novel concept of a metal-coordination-mediated synthesis of a bivalent 99mTc-labeled probe from a monovalent ligand using d-penicillamine (Pen) as a chelating molecule and c(RGDfK) as a model targeting device. The Pen-conjugated c(RGDfK) via a hexanoate linkage (Pen-Hx-c(RGDfK)) provided a bivalent [99mTc]Tc-[(Pen-Hx-c(RGDfK))2 that possessed much higher integrin αvβ3 binding affinity than Pen-Hx-c(RGDfK) and visualized a murine tumor without purification. However, high radioactivity levels were observed in the abdominal regions, which necessitated improved pharmacokinetics of the probes for practical applications. In this study, a pharmacokinetic (PK) modifier was introduced to manipulate the pharmacokinetics of the 99mTc-Pen2-based bivalent probe. The Hx linkage in Pen-Hx-c(RGDfK) was replaced with acetyl-d-serine-d-serine-glycine (Ac-ssG) or hexanoyl-d-serine-d-serine-d-serine (Hx-sss) to prepare Pen-Ac-ssG-c(RGDfK) or Pen-Hx-sss-c(RGDfK). Pen-Ac-ssG-c(RGDfK) impaired the complexation ability of Pen-Hx-c(RGDfK), and a monovalent 99mTc-labeled compound was generated at low ligand concentration. However, Pen-Hx-sss-c(RGDfK) provided the objective bivalent 99mTc-labeled probe in high radiochemical yields at a concentration similar to that of Pen-Hx-c(RGDfK). [99mTc]Tc-[Pen-Hx-sss-c(RGDfK)]2 also possessed stability and integrin αvβ3 binding affinity similar to those of [99mTc]Tc-[Pen-Hx-c(RGDfK)]2. As a result, [99mTc]Tc-[Pen-Hx-sss-c(RGDfK)]2 exhibited tumor and abdominal radioactivity levels similar to and significantly lower than those of [99mTc]Tc-[Pen-Hx-c(RGDfK)]2. These findings indicate the incorporation of a tripeptide PK modifier to Pen-Hx-c(RGDfK) preserved the complexation ability and improved the pharmacokinetics of the resulting 99mTc-labeled bivalent probe without impairing the targeting ability. Thus, the [Pen-Hx-(PK modifier)-(targeting device)] would constitute a basic formulation for preparing the 99mTc-Pen2-based bivalent probes for imaging saturable targets of the body.
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Affiliation(s)
- Tomoya Uehara
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Ayaka Sensui
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Shiori Ishioka
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Yuki Mizuno
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan.,Showa Pharmaceutical University, Machida 194-8543, Japan
| | - Shiori Takahashi
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Hideaki Takemori
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Hiroyuki Suzuki
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Yasushi Arano
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
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Mizuno Y, Uehara T, Jen CW, Akizawa H, Arano Y. The synthesis of a 99mTc-labeled tetravalent targeting probe upon isonitrile coordination to 99mTcI for enhanced target uptake in saturable systems. RSC Adv 2019; 9:26126-26135. [PMID: 35531015 PMCID: PMC9070385 DOI: 10.1039/c9ra04311j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 08/11/2019] [Indexed: 11/21/2022] Open
Abstract
The difference in 2-proton's acidity between Lβ and LG led to dramatically different results of their reactions with [99mTc][Tc(CO)3(OH2)3]+.
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Affiliation(s)
- Yuki Mizuno
- Laboratory of Molecular Imaging and Radiotherapy
- Graduate School of Pharmaceutical Sciences
- Chiba University
- Chiba 260-8675
- Japan
| | - Tomoya Uehara
- Laboratory of Molecular Imaging and Radiotherapy
- Graduate School of Pharmaceutical Sciences
- Chiba University
- Chiba 260-8675
- Japan
| | - Chun-wei Jen
- Laboratory of Molecular Imaging and Radiotherapy
- Graduate School of Pharmaceutical Sciences
- Chiba University
- Chiba 260-8675
- Japan
| | - Hiromichi Akizawa
- Laboratory of Physical Chemistry
- Showa Pharmaceutical University
- Tokyo 194-8543
- Japan
| | - Yasushi Arano
- Laboratory of Molecular Imaging and Radiotherapy
- Graduate School of Pharmaceutical Sciences
- Chiba University
- Chiba 260-8675
- Japan
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Holik HA, Uehara T, Nemoto S, Rokugawa T, Tomizawa Y, Sakuma A, Mizuno Y, Suzuki H, Arano Y. Coordination-Mediated Synthesis of 67Ga-Labeled Purification-Free Trivalent Probes for in Vivo Imaging of Saturable Systems. Bioconjug Chem 2018; 29:2909-2919. [DOI: 10.1021/acs.bioconjchem.8b00337] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Holis A. Holik
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Jl. Raya Bandung-Sumedang KM 21, Sumedang 46363, Indonesia
| | - Tomoya Uehara
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Soki Nemoto
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Takemi Rokugawa
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Yuumi Tomizawa
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Ayako Sakuma
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Yuki Mizuno
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
- Laboratory of Physical Chemistry, Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Hiroyuki Suzuki
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Yasushi Arano
- Laboratory of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
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Taira Y, Uehara T, Tsuchiya M, Takemori H, Mizuno Y, Takahashi S, Suzuki H, Hanaoka H, Akizawa H, Arano Y. Coordination-Mediated Synthesis of Purification-Free Bivalent 99mTc-Labeled Probes for in Vivo Imaging of Saturable System. Bioconjug Chem 2018; 29:459-466. [PMID: 29320158 DOI: 10.1021/acs.bioconjchem.7b00788] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In the synthesis of technetium-99m (99mTc) labeled target-specific ligands, the presence of a large excess of unlabeled ligands over 99mTc in the injectate hinders target accumulation of 99mTc-labeled ligands by competing for target molecules. To circumvent the problem, we recently developed a concept of the metal coordination-mediated multivalency, and proved the concept with a 99mTc-labeled trivalent compound [99mTc(CO)3(CN-RGD)3]+. In this study, D-penicillamine (Pen) was selected as a chelating molecule and a cyclic RGDfK peptide was conjugated to Pen via a hexanoic linkage (Pen-Ahx-c(RGDfK)). 99mTc complexation reaction, and the stability, integrin αvβ3 binding affinity, and biodistribution of the 99mTc-labeled probe were investigated to evaluate the applicability of the concept to bivalent probes. 99mTc-[Pen-Ahx-c(RGDfK)]2 was obtained over 95% radiochemical yields under low Pen-Ahx-c(RGDfK) concentration (50 μM). 99mTc-[Pen-Ahx-c(RGDfK)]2 showed approximately 10-times higher integrin αvβ3 binding affinity than the monovalent compounds, Pen-Ahx-c(RGDfK) and c(RGDyV). In biodistribution studies, the tumor accumulation of 99mTc-[Pen-Ahx-c(RGDfK)]2 was decreased to 77% and 43% of HPLC-purified (Pen-Ahx-c(RGDfK)-free) 99mTc-[Pen-Ahx-c(RGDfK)]2 by the presence of 5 nmol of unlabeled Pen-Ahx-c(RGDfK) and Re-[Pen-Ahx-c(RGDfK)]2, respectively. 99mTc-[Pen-Ahx-c(RGDfK)]2 provided tumor image without removing unlabeled ligand, while a 99mTc-labeled monovalent probe prepared from a monovalent ligand could not. These findings indicate the availability of the design concept to prepare 99mTc-labeled bivalent probes with a variety of 99mTc core and other metallic radionuclides of clinical relevance.
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Affiliation(s)
- Yuichiro Taira
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan
| | - Tomoya Uehara
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan
| | - Masao Tsuchiya
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan
| | - Hideaki Takemori
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan
| | - Yuki Mizuno
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan.,Showa Pharmaceutical University , Machida, 194-8543, Japan
| | - Shiori Takahashi
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan
| | - Hiroyuki Suzuki
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan
| | - Hirofumi Hanaoka
- Graduate School of Medicine, Gunma University , Maebashi, 371-8511, Japan
| | | | - Yasushi Arano
- Graduate School of Pharmaceutical Sciences, Chiba University , Chiba, 260-8675, Japan
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Mizuno Y, Uehara T, Hanaoka H, Endo Y, Jen CW, Arano Y. Purification-Free Method for Preparing Technetium-99m-Labeled Multivalent Probes for Enhanced in Vivo Imaging of Saturable Systems. J Med Chem 2016; 59:3331-9. [PMID: 26999587 DOI: 10.1021/acs.jmedchem.6b00024] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Metallic radionuclides provide target-specific radiolabeled probes for molecular imaging in radiochemical yields sufficient for administration to subjects without purification. However, unlabeled ligands in the injectate can compete for targeted molecules with radiolabeled probes, which eventually necessitates postlabeling purification. Herein we describe a "1 to 3" design to circumvent the issue by taking advantage of inherent coordination properties of technetium-99m ((99m)Tc). A monovalent RGD ligand possessing an isonitrile as a coordinating moiety (CN-RGD) was reacted with [(99m)Tc(CO)3(OH2)3](+) to prepare [(99m)Tc(CO)3(CN-RGD)3](+) in over 95% radiochemical yields. This complex exhibited higher integrin αvβ3 binding affinity than its unlabeled monovalent ligand, primarily due to its multivalency. This compound visualized a murine tumor without removing unlabeled ligands, while a (99m)Tc-labeled monovalent probe derived from a monovalent ligand could not. The metal coordination-mediated synthesis of radiolabeled multivalent probes thereby can be a useful approach for preparing ready-to-use target-specific probes labeled with (99m)Tc and other metallic radionuclides of interest.
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Affiliation(s)
- Yuki Mizuno
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University , 1-8-1 Inohana, Chuo-ku, Chiba 260-8675 Japan
| | - Tomoya Uehara
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University , 1-8-1 Inohana, Chuo-ku, Chiba 260-8675 Japan
| | - Hirofumi Hanaoka
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University , 1-8-1 Inohana, Chuo-ku, Chiba 260-8675 Japan
| | - Yota Endo
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University , 1-8-1 Inohana, Chuo-ku, Chiba 260-8675 Japan
| | - Chun-Wei Jen
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University , 1-8-1 Inohana, Chuo-ku, Chiba 260-8675 Japan
| | - Yasushi Arano
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Sciences, Chiba University , 1-8-1 Inohana, Chuo-ku, Chiba 260-8675 Japan
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Manicum A, Schutte-Smith M, Kemp G, Visser H. Illustration of the electronic influence of coordinated β-diketone type ligands: A kinetic and structural study. Polyhedron 2015. [DOI: 10.1016/j.poly.2014.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Patel MR, Patel RB, Bhatt KK, Patel BG, Gaikwad RV. Paliperidone microemulsion for nose-to-brain targeted drug delivery system: pharmacodynamic and pharmacokinetic evaluation. Drug Deliv 2014; 23:346-54. [PMID: 24865295 DOI: 10.3109/10717544.2014.914602] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE The objective of present study was to develop and evaluate paliperidone (PALI) loaded microemulsion (PALI-ME) for intranasal delivery in the treatment of schizophrenia. MATERIAL AND METHODS The PALI-ME was formulated by the spontaneous microemulsification method and characterized for physicochemical parameters. Pharmacodynamic assessments (apomorphine-induced compulsive behavior and spontaneous motor activity) were performed using mice. All formulations were tagged with (99m)Tc (technetium). Pharmacokinetic evaluation of PALI in the brain was investigated using Swiss albino rats. Brain scintigraphy imaging was performed in rabbits. RESULTS AND DISCUSSION PALI-ME was found stable with average droplet size of 20.01 ± 1.28 nm. In pharmacodynamic studies, significant (p < 0.05) deference in parameters estimated, were found between the treated and control groups. (99m)Tc-tagged PALI solution (PALI-SOL)/PALI-ME/PALI muco-adhesive ME (PALI-MME) was found to be stable and suitable for in vivo studies. Brain-to-blood ratio at all sampling points up to 8 h following intranasal administration of PALI-MME compared to intravenous PALI-ME was found to be 6-8 times higher signifying greater extent of distribution of the PALI in brain. Rabbit brain scintigraphy demonstrated higher intranasal uptake of the PALI into the brain. CONCLUSION This investigation demonstrates a prompt and larger extent of transport of PALI into the brain through intranasal PALI-MME, which may prove beneficial for treatment of schizophrenia.
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Affiliation(s)
- Mrunali R Patel
- a Department of Pharmaceutics & Pharmaceutical Technology , Indukaka Ipcowala College of Pharmacy , New Vallabh Vidyanagar , Gujarat , India
| | - Rashmin B Patel
- b Department of Pharmceutical Chemistry & Quality Assurance , A.R. College of Pharmacy & G.H. Patel Institute of Pharmacy , Vallabh Vidynagar , Gujarat , India
| | - Kashyap K Bhatt
- b Department of Pharmceutical Chemistry & Quality Assurance , A.R. College of Pharmacy & G.H. Patel Institute of Pharmacy , Vallabh Vidynagar , Gujarat , India
| | - Bharat G Patel
- c Department of Pharmacology & Clinical Pharmacy , Charotar University of Science and Technology , Changa , Gujarat , India , and
| | - Rajiv V Gaikwad
- d Veterinary Nuclear Medicine Center , Bombay Veterinary College , Mumbai , India
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Patel RB, Patel MR, Bhatt KK, Patel BG, Gaikwad RV. Evaluation of brain targeting efficiency of intranasal microemulsion containing olanzapine: pharmacodynamic and pharmacokinetic consideration. Drug Deliv 2014; 23:307-15. [PMID: 24845478 DOI: 10.3109/10717544.2014.912694] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The objective of this study was to develop and evaluate olanzapine (OZP) -loaded microemulsions (OZPME) for intranasal delivery in the treatment of schizophrenia. The OZPME was formulated by the spontaneous microemulsification method and characterized for physicochemical parameters. Pharmacodynamic assessments (apomorphine - induced compulsive behavior and spontaneous locomotor activity) were performed using mice. All formulations were radiolabeled with technetium-99 ((99m)Tc), and biodistribution of drug in the brain was investigated using Swiss albino rats. Brain scintigraphy imaging in rabbits was performed to determine the uptake of the OZP into the brain. OZPME were found clear and stable with average globule size of 23.87 ± 1.07 nm. In pharmacodynamic assessments, significant (p < 0.05) difference in parameters estimated were found between the treated and control groups. (99m)Tc-labeled OZP solution (OZPS)/OZPME/OZP mucoadhesive microemulsion (OZPMME) were found to be stable and suitable for in vivo studies. Brain/blood ratio at all sampling points up to 8 h following intranasal administration of OZPMME compared to intravenous OZPME was found to be five to six times higher signifying larger extent of distribution of the OZP in brain. Drug targeting efficiency and direct drug transport were found to be highest for intranasal OZPMME, compared to intravenous OZPME. Furthermore, rabbit brain scintigraphy also demonstrated higher intranasal uptake of the OZP into the brain. This investigation demonstrates a prompt and larger extent of transport of OZP into the brain through intranasal OZPMME, which may prove beneficial for treatment of schizophrenia.
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Affiliation(s)
- Rashmin B Patel
- a A. R. College of Pharmacy & G. H. Patel Institute of Pharmacy , Vallabh Vidyanagar , Gujarat , India
| | - Mrunali R Patel
- b Indukaka Ipcowala College of Pharmacy , New Vallabh Vidyanagar , Gujarat , India
| | - Kashyap K Bhatt
- b Indukaka Ipcowala College of Pharmacy , New Vallabh Vidyanagar , Gujarat , India
| | - Bharat G Patel
- c Charotar University of Science and Technology , Changa , Gujarat , India , and
| | - Rajiv V Gaikwad
- d Veterinary Nuclear Medicine Center , Bombay Veterinary College , Mumbai , Maharashtra , India
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Patel RB, Patel MR, Bhatt KK, Patel BG, Gaikwad RV. Microemulsion-based drug delivery system for transnasal delivery of Carbamazepine: preliminary brain-targeting study. Drug Deliv 2014; 23:207-13. [PMID: 24825492 DOI: 10.3109/10717544.2014.908980] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study reports the development and evaluation of Carbamazepine (CMP)-loaded microemulsions (CMPME) for intranasal delivery in the treatment of epilepsy. The CMPME was prepared by the spontaneous emulsification method and characterized for physicochemical parameters. All formulations were radiolabeled with (99m)Tc (technetium) and biodistribution of CMP in the brain was investigated using Swiss albino rats. Brain scintigraphy imaging in rats was also performed to determine the uptake of the CMP into the brain. CMPME were found crystal clear and stable with average globule size of 34.11 ± 1.41 nm. (99m)Tc-labeled CMP solution (CMPS)/CMPME/CMP mucoadhesive microemulsion (CMPMME) were found to be stable and suitable for in vivo studies. Brain/blood ratio at all sampling points up to 8 h following intranasal administration of CMPMME compared to intravenous CMPME was found to be 2- to 3-fold higher signifying larger extent of distribution of the CMP in brain. Drug targeting efficiency and direct drug transport were found to be highest for CMPMME post-intranasal administration compared to intravenous CMP. Rat brain scintigraphy also demonstrated higher intranasal uptake of the CMP into the brain. This investigation demonstrates a prompt and larger extent of transport of CMP into the brain through intranasal CMPMME, which may prove beneficial for treatment of epilepsy.
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Affiliation(s)
- Rashmin Bharatbhai Patel
- a A. R. College of Pharmacy & G. H. Patel Institute of Pharmacy , Vallabh Vidynagar , Gujarat , India
| | | | - Kashyap K Bhatt
- b Indukaka Ipcowala College of Pharmacy , New Vallabh Vidyanagar , Gujarat , India
| | - Bharat G Patel
- c Department of Pharmacology & Clinical Pharmacology , Charotar University of Science and Technology , Changa , Gujarat , India , and
| | - Rajiv V Gaikwad
- d Veterinary Nuclear Medicine Center , Bombay Veterinary College , Mumbai , India
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Jürgens S, Herrmann WA, Kühn FE. Rhenium and technetium based radiopharmaceuticals: Development and recent advances. J Organomet Chem 2014. [DOI: 10.1016/j.jorganchem.2013.07.042] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Abdelbary GA, Tadros MI. Brain targeting of olanzapine via intranasal delivery of core-shell difunctional block copolymer mixed nanomicellar carriers: in vitro characterization, ex vivo estimation of nasal toxicity and in vivo biodistribution studies. Int J Pharm 2013; 452:300-10. [PMID: 23684658 DOI: 10.1016/j.ijpharm.2013.04.084] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 04/19/2013] [Accepted: 04/28/2013] [Indexed: 10/26/2022]
Abstract
Olanzapine (OZ) is atypical antipsychotic drug that suffers from low brain permeability due to efflux by P-glycoproteins and hepatic first-pass metabolism. The current work aimed to develop OZ-loaded micellar nanocarriers and investigate their nose-to-brain targeting potential. OZ-loaded (5mg/ml) micelles (F1-F12) were prepared, using a Pluronic(®) mixture of L121 and P123, adopting thin-film hydration method. The micelles were evaluated for turbidity, particle size, morphology, drug-entrapment efficiency (EE%), drug-loading characteristics, in vitro drug release and ex vivo nasal toxicity in sheep. The in vivo biodistribution and pharmacokinetic studies in the brain/blood following intravenous (i.v.) and intranasal (i.n.) administrations of technetium-labeled OZ-loaded micelles and OZ-solution were evaluated in rats. Spherical micelles ranging in size from 18.97 to 380.70 nm were successfully developed. (1)H NMR studies confirmed OZ incorporation into micelle core. At a drug:Pluronic(®) L121:Pluronic(®) P123 ratio of 1:8:32 (F11), the micelles achieved a conciliation between kinetic and thermodynamic stability, high drug-EE%, controlled drug-release characteristics and evoked minor histopathological changes in sheep nasal mucosa. The significantly (P<0.05) higher values for F11 micelles (i.n.); brain/blood ratio (0.92), drug targeting index (5.20), drug targeting efficiency (520.26%) and direct transport percentage (80.76%) confirm the development of a promising non-invasive OZ-loaded nose-to-brain delivery system.
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Affiliation(s)
- Ghada Ahmed Abdelbary
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, 11562 Cairo, Egypt
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Pirmettis I, Arano Y, Tsotakos T, Okada K, Yamaguchi A, Uehara T, Morais M, Correia JDG, Santos I, Martins M, Pereira S, Triantis C, Kyprianidou P, Pelecanou M, Papadopoulos M. New (99m)Tc(CO)(3) mannosylated dextran bearing S-derivatized cysteine chelator for sentinel lymph node detection. Mol Pharm 2012; 9:1681-92. [PMID: 22519912 DOI: 10.1021/mp300015s] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The aim of the present study is to synthesize new mannosylated dextran derivative that can be labeled with Tc-99m for potential use in sentinel lymph node detection (SLND). The compound was designed to have a dextran with molecular weight of 10 kDa as a backbone, mannose for binding to mannose receptors of the lymph node and S-derivatized cysteine as a suitable chelator for labeling with [(99m)Tc(H(2)O)(3)(CO)(3)](+) precursor. Reaction of allyl bromide with dextran (MW 11800) yielded the intermediate allyl-dextran (1) with about 40% coupling. Addition of cysteine to allyl-dextran resulted in the S-derivatized cysteine, compound DC15 (2). The final product DCM20 (3) was obtained in good yield after in situ hydrolysis and activation of cyanomethyl tetraacetyl-1-thio-d-mannopyranoside and coupling to DC15. All derivatives were purified by ultrafiltration and characterized by NMR. DC15 and DCM20 were quantitatively labeled with (99m)Tc (>95% radiochemical purity) using the fac-[(99m)Tc(OH(2))(3)(CO)(3)](+) precursor and ligand concentration of 1.5 × 10(-6) M at neutral pH. Both (99m)Tc-labeled compounds (99m)Tc(CO)(3)-DC15 (6) and (99m)Tc(CO)(3)-DCM20 (7) remained stable after 6 h incubation at 37 °C in the presence of excess histidine or cysteine, as well as even after 20-fold dilution and incubation for 24 h at room temperature. The characterization of the compounds 6 and 7 was performed by comparing their HPLC radiochromatograms with those of their rhenium surrogates Re(CO)(3)-DC15 (4) and Re(CO)(3)-DCM20 (5) respectively that were prepared using the precursor [NEt(4)](2)fac-[ReBr(3)(CO)(3)] and characterized by IR and NMR spectroscopy. When injected subcutaneously from the foot pad of mice, (99m)Tc-labeled mannosylated dextran (7) showed accumulation in the popliteal lymph node (SLN in this model) higher than that of non-mannosylated analogue (6) and the (99m)Tc-phytate serving as standard. Compound 7 also exhibited lower radioactivity levels at the injection site compared to (99m)Tc-phytate. The SPECT/CT studies in mice confirmed that 7 accumulated in the popliteal lymph node allowing its clear visualization. The present findings demonstrate that compound 7 ((99m)Tc(CO)(3)-DCM20) is promising and merits further evaluation as a radiopharmaceutical for sentinel lymph node detection.
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Affiliation(s)
- I Pirmettis
- Institute of Radioisotopes and Radiodiagnostic Products, NCSR Demokritos, 15310 Ag. Paraskevi, Athens, Greece.
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13
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Kakkar V, Mishra AK, Chuttani K, Chopra K, Kaur IP. Delivery of Sesamol-Loaded Solid Lipid Nanoparticles to the Brain for Menopause-Related Emotional and Cognitive Central Nervous System Derangements. Rejuvenation Res 2011; 14:597-604. [DOI: 10.1089/rej.2011.1193] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- Vandita Kakkar
- Department of Pharmaceutics, University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
| | - Anil Kumar Mishra
- Government of India, Ministry of Defence, Institute of Nuclear Medicine and Allied Sciences, Brig. S.K. Mazumdar Marg, Delhi, India
| | - Krishna Chuttani
- Government of India, Ministry of Defence, Institute of Nuclear Medicine and Allied Sciences, Brig. S.K. Mazumdar Marg, Delhi, India
| | - Kanwaljit Chopra
- Department of Pharmacology, University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
| | - Indu Pal Kaur
- Department of Pharmaceutics, University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
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14
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Chaudhari KR, Ukawala M, Manjappa AS, Kumar A, Mundada PK, Mishra AK, Mathur R, Mönkkönen J, Murthy RSR. Opsonization, biodistribution, cellular uptake and apoptosis study of PEGylated PBCA nanoparticle as potential drug delivery carrier. Pharm Res 2011; 29:53-68. [PMID: 21744174 DOI: 10.1007/s11095-011-0510-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 06/10/2011] [Indexed: 10/18/2022]
Abstract
PURPOSE For nanocarrier-based targeted delivery systems, preventing phagocytosis for prolong circulation half life is a crucial task. PEGylated poly(n-butylcyano acrylate) (PBCA) NP has proven a promising approach for drug delivery, but an easy and reliable method of PEGylation of PBCA has faced a major bottleneck. METHODS PEGylated PBCA NPs containing docetaxel (DTX) by modified anionic polymerization reaction in aqueous acidic media containing amine functional PEG were made as an single step PEGylation method. In vitro colloidal stability studies using salt aggregation method and antiopsonization property of prepared NPs using mouse macrophage cell line RAW264 were performed. In vitro performance of anticancer activity of prepared formulations was checked on MCF7 cell line. NPs were radiolabeled with 99mTc and intravenously administered to study blood clearance and biodistribution in mice model. RESULTS These formulations very effectively prevented phagocytosis and found excellent carrier for drug delivery purpose. In vivo studies display long circulation half life of PBCA-PEG20 NP in comparison to other formulations tested. CONCLUSIONS The PEGylated PBCA formulation can work as a novel tool for drug delivery which can prevent RES uptake and prolong circulation half life.
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Affiliation(s)
- Kiran Ramanlal Chaudhari
- Pharmacy Department TIFAC Centre of Relevance & Excellence in New Drug Delivery Systems G.H. Patel Pharmacy Building, The Maharaja Sayajirao University of Baroda, Donor's Plaza, Fatehgunj, Vadodara 390002, India
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15
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Banerjee S, Das T, Chakraborty S, Venkatesh M. Emergence and present status of Lu-177 in targeted radiotherapy: the Indian scenario. ACTA ACUST UNITED AC 2011. [DOI: 10.1524/ract.2011.1843] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Abstract
177Lu is presently considered to be a potential radionuclide for the development of agents for radionuclide therapy owing to its favorable nuclear decay characteristics [T
1/2 = 6.65 d, E
β(max) = 0.497 MeV, E
γ
= 113 KeV (6.4%) and 208 KeV (11%)]. While the long half-life of this promising radioisotope offers distinct logistic advantage, particularly, in countries having limited reactor facilities, the feasibility of its large-scale production with adequate specific activity and excellent radionuclidic purity in medium flux research reactors constitute yet another desirable feature. Extensive studies have been carried out to optimize the production of this isotope, with high specific activity and radionuclidic purity by the (n,γ) route using the highest available flux and the optimum irradiation time. The gradual evolution of clin ical grade 177LuCl3 as a new radiochemical, ready for commercial deployment by Radiopharmaceuticals Division, Bhabha Atomic Research Centre, to nuclear medicine centers all over India was accomplished in 2010 in a stepwise manner with the commencement of the production of high specific activity 177Lu from enriched target in 2001. Research on 177Lu has demonstrated its immense potential in radiotherapeutic applications, a direct outcome of which has resulted in indigenous development of two agents viz.
177Lu-EDTMP and 177Lu-DOTA-TATE presently being evaluated in human patients for palliative care of bone pain due to skeletal metastases and treatment of malignancies of neuroendocrine origin, respectively. Using locally produced 177Lu, the radiolabeling of a plethora of other molecules with potential applicability in radiation synovectomy and targeted therapy of malignant tumors have been successfully demonstrated. A few of these agent such as a novel 177Lu-labeled porphyrin has shown considerable promise in initial studies and is presently evaluated. In the present article, our research efforts toward standardization of production methodology of 177Lu in high specific activity and its utilization in the devel opment of agents for targeted radiotherapy are being reported.
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Affiliation(s)
| | - Tapas Das
- Bhabha Atomic Research Centre, Radiopharmaceuticals Division, Trombay, Mumbai 400085, Indien
| | - S. Chakraborty
- Bhabha Atomic Research Centre, Radiopharmaceuticals Division, Trombay, Mumbai 400085, Indien
| | - Meera Venkatesh
- Bhabha Atomic Research Centre, Radiopharmaceuticals Division, Trombay, Mumbai 400085, Indien
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16
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Florence K, Manisha L, Kumar BA, Ankur K, Kumar MA, Ambikanandan M. Intranasal clobazam delivery in the treatment of status epilepticus. J Pharm Sci 2010; 100:692-703. [PMID: 20799366 DOI: 10.1002/jps.22307] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Revised: 06/16/2010] [Accepted: 06/27/2010] [Indexed: 11/11/2022]
Abstract
The aim of the present investigation was to prepare and characterize clobazam mucoadhesive microemulsion (CZMME) to assess brain drug uptake and protection against pentylenetetrazole (PTZ)-induced convulsions in mice. Clobazam microemulsion (CZME) and CZMME were prepared by titration method and characterized. Brain uptake and pharmacokinetic parameters were calculated from drug concentration in mice brain versus time plots following intranasal administration of radiolabeled CZME and CZMME, intravenous and intranasal administration of radiolabeled clobazam solution. Gamma scintigraphy imaging of rabbit brain following intranasal administration was performed. Formulations were investigated for the onset of seizures in PTZ-challenged mice. Brain targeting efficiency and direct nose-to-brain transport percentage for mucoadhesive microemulsion suggested an improved brain uptake following intranasal administration. The findings were supported by gamma scintigraphy images. Delay in onset of PTZ-induced seizures with CZMME compared with positive control and placebo-treated groups confirmed the improved brain uptake. However, extensive animal studies followed by clinical trials are necessary to develop a product suitable for emergencies of acute seizures in status epilepticus and patients suffering from drug tolerance and hepatic impairment on long-term use in treatment of epilepsy, schizophrenia, and anxiety.
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Affiliation(s)
- Kiruba Florence
- Pharmacy Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat, India
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17
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Donovan AC, Valliant JF. Preparation and evaluation of reagents for tagging amino and thiol groups with fluorous stannanes. A convenient method for producing radioiodinated compounds in high effective specific activity. J Labelled Comp Radiopharm 2010. [DOI: 10.1002/jlcr.1807] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Bartholomä MD, Louie AS, Valliant JF, Zubieta J. Technetium and Gallium Derived Radiopharmaceuticals: Comparing and Contrasting the Chemistry of Two Important Radiometals for the Molecular Imaging Era. Chem Rev 2010; 110:2903-20. [DOI: 10.1021/cr1000755] [Citation(s) in RCA: 250] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Mark D. Bartholomä
- Department of Chemistry, Syracuse University, Syracuse, New York 13244, and Department of Chemistry, McMaster University, Hamilton, Canada ON L8S 4M1
| | - Anika S. Louie
- Department of Chemistry, Syracuse University, Syracuse, New York 13244, and Department of Chemistry, McMaster University, Hamilton, Canada ON L8S 4M1
| | - John F. Valliant
- Department of Chemistry, Syracuse University, Syracuse, New York 13244, and Department of Chemistry, McMaster University, Hamilton, Canada ON L8S 4M1
| | - Jon Zubieta
- Department of Chemistry, Syracuse University, Syracuse, New York 13244, and Department of Chemistry, McMaster University, Hamilton, Canada ON L8S 4M1
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19
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Sundararajan C, Besanger TR, Labiris R, Guenther KJ, Strack T, Garafalo R, Kawabata TT, Finco-Kent D, Zubieta J, Babich JW, Valliant JF. Synthesis and Characterization of Rhenium and Technetium-99m Labeled Insulin. J Med Chem 2010; 53:2612-21. [DOI: 10.1021/jm100096c] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chitra Sundararajan
- Departments of Chemistry and Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Travis R. Besanger
- Departments of Chemistry and Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Renee Labiris
- Department of Medicine, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Katharina J. Guenther
- Departments of Chemistry and Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Thomas Strack
- Pfizer, Inc., 235 East 42nd Street 3/58, New York, New York 10017
| | - Robert Garafalo
- Pfizer, Inc., 235 East 42nd Street 3/58, New York, New York 10017
| | | | | | - Jon Zubieta
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York 13244
| | - John W. Babich
- Molecular Insight Pharmaceuticals, Inc., Cambridge, Massachusetts 02142
| | - John F. Valliant
- Departments of Chemistry and Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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20
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Sharma G, Mishra AK, Mishra P, Misra A. Intranasal cabergoline: pharmacokinetic and pharmacodynamic studies. AAPS PharmSciTech 2009; 10:1321-30. [PMID: 19894122 DOI: 10.1208/s12249-009-9329-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Accepted: 10/13/2009] [Indexed: 12/18/2022] Open
Abstract
Aims of this investigation were to prepare and characterize cabergoline intranasal microemulsion formulations, determine brain drug delivery through biodistribution using technetium-99m (99mTc) as a tracer, and assess its performance pharmacodynamically in weight control. Cabergoline microemulsions of different compositions were prepared by water titration method and characterized for globule size and zeta potential. Microemulsion with maximum drug solubilization and stability was considered optimal and taken for further studies with or without addition of mucoadhesive agent. Pharmacokinetics of optimized 99mTc-labeled cabergoline formulations and 99mTc-labeled drug solution were studied by estimating radioactivity in brain and blood of albino rats post intranasal, intravenous, and oral administrations. To confirm localization of drug in brain following intranasal, intravenous, and oral administrations, gamma scintigraphy imaging was also performed. To assess weight control performance of formulations, body weight, white adipose tissue mass, serum lipids, leptin, and prolactin were determined before and after 40 days of intranasal administrations of these formulations to Wistar rats. Microemulsions were found to be stable both physically and chemically when stored at various stress conditions. Brain/blood uptake ratios, drug targeting efficiency, and direct drug transport were found to be highest for drug mucoadhesive microemulsion followed by drug microemulsion and drug solution post-intranasal administration compared to intravenous drug microemulsion. Significant (p<0.05) reduction in assessed pharmacodynamic parameters was observed after intranasal administration of mucoadhesive microemulsion against control group. The results of the studies conclusively demonstrate that intranasal microemulsion formulations developed in this investigation are stable and can deliver cabergoline selectively and in higher amounts to the brain compared to both drug administrations as a solution intranasally or microemulsion intravenously. The results also demonstrate reduction in weight, adipose tissue mass, serum lipids, and serum prolactin after intranasal administration of drug microemulsion. Hence, long-term studies in at least two more animal models followed by extensive clinical evaluation can safely result into a product for clinical use.
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21
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Donovan AC, Valliant JF. Fluorous Isocyanates: Convenient Synthons for the Preparation of Radioiodinated Compounds in High Effective Specific Activity. J Org Chem 2009; 74:8133-8. [DOI: 10.1021/jo901475d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Amanda C. Donovan
- Departments of Chemistry and Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main St. West, Hamilton, Ontario, Canada L8S 4M1
| | - John F. Valliant
- Departments of Chemistry and Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main St. West, Hamilton, Ontario, Canada L8S 4M1
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22
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Richard C, Chaumet-Riffaud P, Belland A, Parat A, Contino-Pepin C, Bessodes M, Scherman D, Pucci B, Mignet N. Amphiphilic perfluoroalkyl carbohydrates as new tools for liver imaging. Int J Pharm 2009; 379:301-8. [DOI: 10.1016/j.ijpharm.2009.05.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 04/09/2009] [Accepted: 05/18/2009] [Indexed: 10/20/2022]
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23
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Kumar M, Misra A, Mishra AK, Mishra P, Pathak K. Mucoadhesive nanoemulsion-based intranasal drug delivery system of olanzapine for brain targeting. J Drug Target 2009; 16:806-14. [PMID: 18988064 DOI: 10.1080/10611860802476504] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The objective of the present study was to optimize olanzapine nanoemulsion (ONE), for nose-to-brain delivery. The nanoemulsions and olanzapine mucoadhesive nanoemulsions (OMNEs) were prepared using water titration method and characterized for technical and electrokinetic properties. Biodistribution of nanoemulsions and olanzapine solution (OS) in the brain and blood of rats following intranasal (intranasal) and intravenous (intravenous) administrations were examined using optimized technetium-labeled ((99m)Tc-labeled) olanzapine formulations. The brain/blood uptake ratios of 0.45, 0.88, 0.80, and 0.04 of OS (intranasal), ONE (intranasal), OMNE (intranasal), ONE (intravenous), respectively, at 0.5 h are indicative of direct nose-to-brain transport (DTP). Higher % drug targeting efficiency (%DTE) and %DTP for mucoadhesive nanoemulsions indicated effective brain targeting of olanzapine among the prepared nanoemulsions. Gamma scintigraphy imaging of the rat brain conclusively demonstrated rapid and larger extent of transport of olanzapine by OMNE (intranasal), when compared with OS (intranasal), ONE (intranasal), and ONE (intravenous), into the rat brain.
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Affiliation(s)
- Mukesh Kumar
- Department of Pharmaceutics, Rajiv Academy for Pharmacy, Mathura, India
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24
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Bartholomä M, Valliant J, Maresca KP, Babich J, Zubieta J. Single amino acid chelates (SAAC): a strategy for the design of technetium and rhenium radiopharmaceuticals. Chem Commun (Camb) 2009:493-512. [PMID: 19283279 DOI: 10.1039/b814903h] [Citation(s) in RCA: 168] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Mark Bartholomä
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, USA
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25
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Vyas TK, Babbar AK, Sharma RK, Misra A. Intranasal mucoadhesive microemulsions of zolmitriptan: Preliminary studies on brain-targeting. J Drug Target 2008; 13:317-24. [PMID: 16199375 DOI: 10.1080/10611860500246217] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The aim of this investigation was to prepare microemulsions containing zolmitriptan (ZT) for rapid drug delivery to the brain to treat acute attacks of migraine and to characterize microemulsions and evaluate biodistribution in rats. Zolmitriptan microemulsions (ZME) were prepared using the titration method and were characterized for globule size distribution and zeta potential. ZT was radiolabeled using (99m)Tc (technetium) and radiolabeled-drug formulations of ZT were used to carry out biodistribution of drug in the brain of Swiss albino rats after intranasal and intravenous administration. The pharmacokinetic parameters, drug targeting efficiency (%DTE) and direct nose-to-brain drug transport (%DTP) were calculated. Brain scintigraphy imaging in rats were also performed to ascertain the uptake of drug into the brain. ZME were transparent and stable with mean globule size of 35 +/- 25 nm and zeta potential of - 38- - 52 mV. (99m)Tc-labeled-drug formulations of ZT were found to be stable and suitable to perform in vivo studies. Following intranasal administrations of zolmitriptan mucoadhesive microemulsion (ZMME), ZME, Zolmitriptan solution (ZS) and intravenous administration of ZS, brain/blood uptake ratios at 0.50 h were found to be 0.70, 0.56, 0.27 and 0.13, respectively, indicating effective brain-targeting following intranasal administration of ZMME. Comparing intranasal administration of ZMME with intravenous administration of ZME, the %DTE and %DTP were found higher indicating effective drug transport following intranasal administration and highest brain-targeting following ZMME administration. Rat brain scintigrams showed substantial uptake of drug into the brain after intranasal administration of ZMME. Studies of this investigation conclusively demonstrated rapid and larger extent of transport into the rat brain following intranasal administration of ZMME and can play a promising role in the treatment of acute attacks of migraine.
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Affiliation(s)
- Tushar K Vyas
- The Maharaja Sayajirao University of Baroda, Pharmacy Department, Faculty of Technology and Engineering, Kalabhavan, Post Box No.51, Vadodara, 390 001, Gujarat, India
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26
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McIntee JW, Sundararajan C, Donovan AC, Kovacs MS, Capretta A, Valliant JF. A Convenient Method for the Preparation of Fluorous Tin Derivatives for the Fluorous Labeling Strategy. J Org Chem 2008; 73:8236-43. [DOI: 10.1021/jo8013287] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jason W. McIntee
- Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Ontario, Canada L8S 4M1
| | - Chitra Sundararajan
- Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Ontario, Canada L8S 4M1
| | - Amanda C. Donovan
- Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Ontario, Canada L8S 4M1
| | - Michael S. Kovacs
- Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Ontario, Canada L8S 4M1
| | - Alfredo Capretta
- Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Ontario, Canada L8S 4M1
| | - John F. Valliant
- Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Ontario, Canada L8S 4M1
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Donovan AC, Valliant JF. A convenient solution-phase method for the preparation of meta-iodobenzylguanidine in high effective specific activity. Nucl Med Biol 2008; 35:741-6. [DOI: 10.1016/j.nucmedbio.2008.07.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Revised: 07/14/2008] [Accepted: 07/24/2008] [Indexed: 11/26/2022]
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28
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Shah P, Jogani V, Mishra P, Mishra AK, Bagchi T, Misra A. In Vitro Assessment of Acyclovir Permeation Across Cell Monolayers in the Presence of Absorption Enhancers. Drug Dev Ind Pharm 2008; 34:279-88. [DOI: 10.1080/03639040701655952] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Causey PW, Besanger TR, Schaffer P, Valliant JF. Expedient Multi-Step Synthesis of Organometallic Complexes of Tc and Re in High Effective Specific Activity. A New Platform for the Production of Molecular Imaging and Therapy Agents. Inorg Chem 2008; 47:8213-21. [DOI: 10.1021/ic800775w] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Patrick W. Causey
- McMaster Nuclear Reactor, Department of Chemistry, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Canada, L8S 4M1
| | - Travis R. Besanger
- McMaster Nuclear Reactor, Department of Chemistry, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Canada, L8S 4M1
| | - Paul Schaffer
- McMaster Nuclear Reactor, Department of Chemistry, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Canada, L8S 4M1
| | - John F. Valliant
- McMaster Nuclear Reactor, Department of Chemistry, and McMaster Institute of Applied Radiation Sciences (McIARS), McMaster University, Hamilton, Canada, L8S 4M1
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Eckelman WC, Reba RC, Kelloff GJ. Targeted imaging: an important biomarker for understanding disease progression in the era of personalized medicine. Drug Discov Today 2008; 13:748-59. [PMID: 18617011 DOI: 10.1016/j.drudis.2008.05.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Revised: 04/30/2008] [Accepted: 05/22/2008] [Indexed: 11/16/2022]
Abstract
The key to applying targeted imaging to personalized medicine is the choice of the right radiolabeled probe for the right target for the right disease following the lead of pharmaceutical development. The imaging approach differs depending on whether the target is a single disease control point (e.g. a specific receptor or transport protein linked to the mechanistic activity of a drug) or a general disease control point applicable to a number of treatment paradigms (e.g. proliferation, angiogenesis, inflammation). But in either case, the number of control points must be small given the time constraints on molecular imaging procedures in the clinic. Regardless of the choice, the radiotracer must be validated as binding to the target with the appropriate pharmacokinetics and pharmacodynamics for effective external imaging. Such an imaging agent developed in concert with drug development has a built in synergy that will accelerate the drug development process, targeted imaging and personalized medicine as well.
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31
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Kumar M, Misra A, Babbar A, Mishra A, Mishra P, Pathak K. Intranasal nanoemulsion based brain targeting drug delivery system of risperidone. Int J Pharm 2008; 358:285-91. [DOI: 10.1016/j.ijpharm.2008.03.029] [Citation(s) in RCA: 293] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2007] [Revised: 03/05/2008] [Accepted: 03/09/2008] [Indexed: 11/24/2022]
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32
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Intranasal Mucoadhesive Microemulsion of Tacrine to Improve Brain Targeting. Alzheimer Dis Assoc Disord 2008; 22:116-24. [DOI: 10.1097/wad.0b013e318157205b] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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33
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Volkert W, Karra S, Gali H, Schibli R, Katti K. Bifunctional Chelation Systems Based on Hydroxymethyl Phosphine-Based Donor Groups. PHOSPHORUS SULFUR 2008. [DOI: 10.1080/10426509908546288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- W.A. Volkert
- a Dept. of Radiology and Research Reactor Center , Univ. of Missouri Columbia , Missouri, 65211, USA
- b Dept. of Radiology and Columbia , Missouri, 65211, USA
- c Dept. of Radiology and Columbia , Missouri, 65211, USA
- d Dept. of Radiology and Columbia , Missouri, 65211, USA
- e Dept. of Radiology and Research Service , H.S. Truman VA Memorial Hosp. , Columbia, Missouri, 65211, USA
| | - S.R. Karra
- a Dept. of Radiology and Research Reactor Center , Univ. of Missouri Columbia , Missouri, 65211, USA
- b Dept. of Radiology and Columbia , Missouri, 65211, USA
- c Dept. of Radiology and Columbia , Missouri, 65211, USA
- d Dept. of Radiology and Columbia , Missouri, 65211, USA
- e Dept. of Radiology and Research Service , H.S. Truman VA Memorial Hosp. , Columbia, Missouri, 65211, USA
| | - H. Gali
- a Dept. of Radiology and Research Reactor Center , Univ. of Missouri Columbia , Missouri, 65211, USA
- b Dept. of Radiology and Columbia , Missouri, 65211, USA
- c Dept. of Radiology and Columbia , Missouri, 65211, USA
- d Dept. of Radiology and Columbia , Missouri, 65211, USA
- e Dept. of Radiology and Research Service , H.S. Truman VA Memorial Hosp. , Columbia, Missouri, 65211, USA
| | - R. Schibli
- a Dept. of Radiology and Research Reactor Center , Univ. of Missouri Columbia , Missouri, 65211, USA
- b Dept. of Radiology and Columbia , Missouri, 65211, USA
- c Dept. of Radiology and Columbia , Missouri, 65211, USA
- d Dept. of Radiology and Columbia , Missouri, 65211, USA
- e Dept. of Radiology and Research Service , H.S. Truman VA Memorial Hosp. , Columbia, Missouri, 65211, USA
| | - K.V. Katti
- a Dept. of Radiology and Research Reactor Center , Univ. of Missouri Columbia , Missouri, 65211, USA
- b Dept. of Radiology and Columbia , Missouri, 65211, USA
- c Dept. of Radiology and Columbia , Missouri, 65211, USA
- d Dept. of Radiology and Columbia , Missouri, 65211, USA
- e Dept. of Radiology and Research Service , H.S. Truman VA Memorial Hosp. , Columbia, Missouri, 65211, USA
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Abstract
In the treatment of Alzheimer's disease tacrine, a cholinesterase inhibitor, is not the drug of choice due to its low oral bioavailability, extensive hepatic first-pass effect, rapid clearance from the systemic circulation, pronounced hepatotoxicity, and the availability of drugs better than tacrine in the same pharmacological class. Hence, the aim of this investigation was to ascertain the possibility of direct nose-to-brain delivery of tacrine to improve bioavailability, to avoid the first-pass effect and to minimize hepatotoxicity. Tacrine solution (TS) in propylene glycol was radiolabelled with (99m)Tc (technetium) and administered in BALB/c mice intranasally (i.n.) and intravenously (i.v.). Drug concentrations in blood and brain were determined at predetermined time intervals post dosing. Drug targeting efficiency (DTE %) and the brain drug direct transport percentage (DTP %) were calculated to evaluate the brain targeting efficiency. Brain scintigraphy imaging in rabbits was performed to ascertain the uptake of the drug into the brain. Tacrine solution was effectively labelled with (99m)Tc and was found to be stable and suitable for in-vivo studies. Following intranasal administration tacrine was delivered quickly (T(max) 60 min) to the brain compared with intravenous administration (T(max) 120 min). The brain/blood ratios of the drug were found to be higher for [(99m)Tc]TS(i.n.) compared with [(99m)Tc]TS(i.v.) at all time points. The DTE (207.23%) and DTP (51.75%) following intranasal administration suggested that part of tacrine was directly transported to brain from the nasal cavity. Rabbit brain scintigraphy imaging showed higher uptake of the drug into the brain following intranasal administration compared with intravenous administration. The results showed that tacrine could be directly transported into the brain from the nasal cavity and intranasal administration resulted in higher bioavailability of drug with reduced distribution into non-targeted tissues. This selective localization of tacrine in the brain may be helpful in reducing dose, frequency of dosing and dose-dependent side effects, and may prove an interesting new approach in delivery of the drug to the brain for the treatment of Alzheimer's disease.
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Affiliation(s)
- Viral V Jogani
- Department of Pharmacy, Faculty of Technology & Engineering, The Maharaja Sayajirao University of Baroda, Post Box No. 51, Kalabhavan, Vadodara 390001, India
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Chazov EI, Bespalova JD, Arefieva TI, Kukhtina NB, Sidorova MV, Provatorov SI, Krasnikova TL. The peptide analogue of MCP-1 65-76 sequence is an inhibitor of inflammation. Can J Physiol Pharmacol 2007; 85:332-40. [PMID: 17612642 DOI: 10.1139/y07-008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Inflammation plays an important role in vessel wall remodeling that occurs in atherosclerosis and postangioplasty restenosis. Monocytic chemoattractant protein-1 (MCP-1) is one of the main attractors of monocytes and some lymphocyte subsets to the damaged vessel. The aims of the study were to confirm MCP-1 participation in the development of acute coronary syndromes, to produce the potential MCP-1 peptide antagonist, and to investigate its effects in vitro and in vivo in different animal models of inflammation. MCP-1 plasma concentration was measured by ELISA (enzyme-linked immunosorbent assay). Chemokine receptor expression by cells isolated from human atherosclerotic lesions was assessed by direct immunofluorescence and flow cytometry. MCP-1 sequence was analyzed with Peptide Companion software and peptides were synthesized using Fmoc strategy. The peptide resistance to degradation was checked by 1H-NMR spectroscopy. The peptide effect on MCP-1-stimulated cell migration was studied in Boyden chamber and in mouse air pouch model, and its influence on lipopolysaccharide (LPS)-induced inflammatory cell recruitment was investigated in models of subcutaneous inflammation in rats and nonhuman primates. We revealed nearly a 2-fold increase of MCP-1 plasma level in patients with unstable angina in comparison with patients with stable angina. The atherosclerotic plaque specimens obtained from patients with unstable angina contained a significant amount of chemokine receptor-expressing leukocytes. Peptide from MCP-1 C-terminal 65-76 sequence (peptide X) inhibited MCP-1-stimulated monocytic cell migration in vitro and in vivo. Peptide X labeled with 99mTc accumulated specifically at sites of inflammation in rats. Peptide X administrated i.m and i.v. suppressed monocyte and granulocyte recruitment induced by subcutaneous injection of LPS in the back of rats and non-human primates. Our data demonstrate that MCP-1-mediated chemotaxis could be responsible for atherosclerotic plaque "destabilization". Peptide X may represent a new class of anti-inflammatory drugs to be used in cardiology.
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Affiliation(s)
- Evgeny I Chazov
- Russian Cardiology Research Complex, 3 Cherepkovskaya, 15a, Moscow 121552 Russia
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Shah P, Jogani V, Mishra P, Mishra AK, Bagchi T, Misra A. Modulation of Ganciclovir Intestinal Absorption in Presence of Absorption Enhancers. J Pharm Sci 2007; 96:2710-22. [PMID: 17680662 DOI: 10.1002/jps.20888] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The purpose of this investigation was to study the influences of absorption enhancers in increasing oral bioavailability of Ganciclovir (GAN) by assessing the transepithelial permeation across cell monolayers in vitro and bioavailability in rats in vivo. The permeation of GAN across Caco-2 and MDCK cell monolayers in the absence/presence of dimethyl-beta-cyclodextrin (DMbetaCD), chitosan hydrochloride (CH), sodium lauryl sulphate (SLS), and their combinations was studied for a 2-h period. GAN was administered to rats in absence/presence of absorption enhancers and drug contents in plasma were estimated. We found that the apparent permeability coefficient (Papp) of GAN in absence of absorption enhancers (control) were 0.261 +/- 0.072 x 10(-6) and 0.486 +/- 0.063 x 10(-6) cm/s in Caco-2 and MDCK cell monolayers, respectively, whereas in the presence of DMbetaCD, CH, SLS, and their combinations, Papp of GAN increased by 5- to 25-fold and 7- to 33-fold as compared to control in Caco-2 and MDCK cell monolayers, respectively. However, in rats, the maximum enhancement in bioavailability of GAN during coadministration of these absorption enhancers was only fivefold compared to GAN control. To conclude, the absorption enhancers-DMbetaCD, CH, SLS, and their combinations demonstrated significant improvement in transepithelial permeation and bioavailability of GAN.
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Affiliation(s)
- Pranav Shah
- Department of Pharmacy, Faculty of Technology & Engineering, The Maharaja Sayajirao University of Baroda, P.O. Box 51, Kalabhavan, Vadodara 390 001, India
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Park KH, Song HC, Na K, Bom HS, Lee KH, Kim S, Kang D, Lee DH. Ionic strength-sensitive pullulan acetate nanoparticles (PAN) for intratumoral administration of radioisotope: Ionic strength-dependent aggregation behavior and 99mTechnetium retention property. Colloids Surf B Biointerfaces 2007; 59:16-23. [PMID: 17532195 DOI: 10.1016/j.colsurfb.2007.04.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2007] [Revised: 04/07/2007] [Accepted: 04/11/2007] [Indexed: 10/23/2022]
Abstract
In order to design an effective intratumoral radioisotope carrier, a self-assembled nanoparticle evidencing ionic strength (IS)-sensitivity from a polysaccharide derivative (pullulan acetate nanoparticle (PAN)) was prepared via dialysis. The PAN had a spherical shape in a range of size of 50-130 nm and a low critical aggregation concentration (CAC) (<8 microg/mL). With increases in the IS of the dialysis media (IS(dia)), the CAC of PAN was reduced gradually and the rigidity of the hydrophobic core in PAN was increased. This suggests that the property of PAN was altered more hydrophobically at high IS values. The stabilities of PANs prepared from various IS(dia) were also monitored with changes in the turbidity and particle size in different IS solutions. In the case of PAN prepared at an IS(dia)=0.0, the turbidity was dramatically reduced with increasing IS due to the facilitation of aggregation between the particles, whereas in the other cases, these changes were negligible. This finding indicates that PAN prepared in distilled water (IS=0.0) can be readily injected as the consequence of its nano-size, and accumulates quickly, then remains in the tumor site for a considerable period (IS=0.15). In order to closely estimate the potential of PAN as a radioisotope carrier, the radioisotope labeling efficiency of PAN with no chelating agents was evaluated. PAN evidenced a high degree of (99m)Technetium ((99m)Tc) labeling efficiency (approximately 98%). The percentage retention rate (%RR) of the (99m)Tc-labeled PAN was significantly longer than that of the free (99m)Tc (p<0.05), due largely to PAN's IS-sensitivity. In conclusion, PAN may constitute a new approach to the achievement of maximal radioisotope efficiency with regard to intratumoral administration.
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Affiliation(s)
- Keun-Hong Park
- College of Medicine, Pochon CHA University, Cell and Gene Therapy Research Institute 605, Yeoksam 1-dong, Kangnam-gu, Seoul 135-081l, Korea
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Shah PJ, Jogani VV, Mishra P, Mishra AK, Bagchi T, Misra AR. Role of 99mTc-mannitol and 99mTc-PEG in the assessment of paracellular integrity of cell monolayers. Nucl Med Commun 2007; 28:653-9. [PMID: 17625388 DOI: 10.1097/mnm.0b013e32822a0e8b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM To assess the role of 99mTc-mannitol and 99mTc-polyethylene glycol 4000 in the evaluation of paracellular integrity of Caco-2 and Madine-Darby canine kidney (MDCK) cell monolayers, and confirm it in the presence of absorption promoters. METHODS Radiolabelling of mannitol and polyethylene glycol was performed by a simple reduction method. Transepithelial electrical resistance values were measured to gain information regarding the integrity of tight junctions of Caco-2 and MDCK cell monolayers. Permeabilities of 99mTc-mannitol/99mTc-polyethylene glycol across cell monolayers were studied in the absence and presence of absorption promoters, namely dimethyl-beta-cyclodextrin, chitosan hydrochloride and sodium lauryl sulfate, and during recovery studies to assess paracellular integrity. RESULTS Values for the apparent permeability coefficient (Papp) of Tc-mannitol were found to be 0.286 x 10 cm x s(-1) and 0.507 x 10 cm x s(-1) in Caco-2 and MDCK cell monolayers, respectively, whereas corresponding values for 99mTc-polyethylene glycol were 0.046 x 10 cm x s(-1) and 0.065 x 10 cm x s(-1). The insignificant Papp values of the marker molecules demonstrated the paracellular integrity of the cell monolayers. Significant increases in the Papp values in the presence of absorption promoters and their combinations due to opening of paracellular pathways and a return of Papp values to almost baseline values during recovery studies confirm the role of these marker molecules in the assessment of paracellular integrity of cell monolayers. CONCLUSION 99mTc-labelled marker molecules can be attractive, useful and viable alternatives to the conventionally used markers in the assessment of paracellular integrity because of the absence of tissue-damaging corpuscular radiation and the ease of production of radiochemically pure and stable molecules at a reasonable cost.
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Affiliation(s)
- Pranav J Shah
- Department of Pharmacy, Faculty of Technology & Engineering, Institute of Nuclear Medicine and Allied Sciences, New Delhi, India
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Djokić D, Janković D. Biological evaluation and comparison of three different procedures for labelling of amino acids tyrosine and lysine with technetium-99m. J Labelled Comp Radiopharm 2007. [DOI: 10.1002/jlcr.1205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Lazarova N, Babich J, Valliant J, Schaffer P, James S, Zubieta J. Thiol- and thioether-based bifunctional chelates for the {M(CO)3}+ core (M = Tc, Re). Inorg Chem 2006; 44:6763-70. [PMID: 16156635 DOI: 10.1021/ic050735a] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
By analogy to the recently described single amino acid chelate (SAAC) technology for complexation of the {M(CO)3}+ core (M = Tc, Re), a series of tridentate ligands containing thiolate and thioether groups, as well as amino and pyridyl nitrogen donors, have been prepared: (NC5H4CH2)2NCH2CH2SEt (L1); (NC5H4CH2)2NCH2CH2SH (L2); NC5H4CH2N(CH2CH2SH)2 (L3); (NC5H4CH2)N(CH2CH2SH)(CH2CO2R) [R = H (L4); R = -C2H5 (L5). The {Re(CO)3}+ core complexes of L1-L5 were prepared by the reaction of [Re(CO)3(H2O)3]Br or [NEt4]2[Re(CO)3Br3] with the appropriate ligand in methanol and characterized by infrared spectroscopy, 1H and 13C NMR spectroscopy, mass spectrometry, and in the case of [Re(CO)3(L2)] (Re-2) and [Re(CO)3(L1)Re(CO)3Br2] (Re-1a) by X-ray crystallography. The structure of Re-2 consists of discrete neutral monomers with a fac-Re(CO)3 coordination unit and the remaining coordination sites occupied by the amine, pyridyl, and thiolate donors of L2, leaving a pendant pyridyl arm. In contrast, the structure of Re-1a consists of discrete binuclear units, constructed from a {Re(CO)3(L1)}+ subunit linked to a {Re(CO)3Br2}- group through the sulfur donor of the pendant thioether arm. The series of complexes establishes that thiolate donors are effective ligands for the {M(CO)3}+ core and that a qualitative ordering of the coordination preferences of the core may be proposed: pyridyl nitrogen approximately thiolate > carboxylate > thioether sulfur > thiophene sulfur. The ligands L1 and L2 react cleanly with [99mTc(CO)3(H2O)3]+ in H2O/DMSO to give [99mTc(CO)3(L1)]+ (99m)Tc-1) and [99mTc(CO)3(L2)] (99mTc-2), respectively, in ca. 90% yield after HPLC purification. The Tc analogues 99mTc-1 and 99mTc-2 were subjected to ligand challenges by incubating each in the presence of 1000-fold excesses of both cysteine and histidine. The radiochromatograms showed greater than 95% recovery of the complexes.
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Affiliation(s)
- Neva Lazarova
- Department of Chemistry, Syracuse University, Syracuse, NY 13244-4100, USA
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41
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Wei L, Babich JW, Ouellette W, Zubieta J. Developing the {M(CO)3}+ Core for Fluorescence Applications: Rhenium Tricarbonyl Core Complexes with Benzimidazole, Quinoline, and Tryptophan Derivatives. Inorg Chem 2006; 45:3057-66. [PMID: 16562962 DOI: 10.1021/ic0517319] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tridentate ligands derived from benzimidazole, quinoline, and tryptophan have been synthesized, and their reactions with [NEt4]2[Re(CO)3Br3] have been investigated. The complexes 1-4 and 6 and 7 exhibit fac-{Re(CO)3N3} coordination geometry in the cationic molecular units, while 5 exhibits fac-{Re(CO)3N2O} coordination for the neutral molecular unit, where N3 and N2O refer to the ligand donor groups. The ligands bis(1-methyl-1H-benzoimidazol-2-ylmethyl)amine (L1), [bis(1-methyl-1H-benzoimidazol-2-ylmethyl)amino]acetic acid ethyl ester (L2), [bis(1-methyl-1H-benzoimidazol-2-ylmethy)amino]acetic acid methyl ester (L3), [bis(quinolin-2-ylmethyl)amino]acetic acid methyl ester (L4), 3-(1-methyl-1H-indol-3-yl)-2-[(pyridin-2-ylmethyl)amino]propionic acid (L5), 2-[bis(pyridin-2-ylmethyl)amino]-3-(1-methyl-1H-indol-3-yl)propionic acid (L6), and 2-[bis(quinolin-2-ylmethyl)amino]-3-(1-methyl-1H-indol-3-yl)propionic acid (L7) were obtained in good yields and characterized by elemental analysis, 1D and 2D NMR, and high-resolution mass spectrometry (HRMS). The rhenium complexes were obtained in 70-85% yields and characterized by elemental analysis, 1D and 2D NMR, HRMS, IR, UV, and luminescence spectroscopy, as well as X-ray crystallography for [Re(CO)3(L1)]Br (1), {[Re(CO)3(L2)]Br}2.NEt4Br . 8.5H2O (3(2).NEt4Br . 8.5H2O), [Re(CO)3(L4)]Br (4), and [Re(CO)3(L6)]Br (6). Crystal data for C21H19BrN5O3Re (1): monoclinic, P2(1)/c, a = 13.1851(5) A, b = 16.1292(7) A, c = 10.2689(4) A, beta = 99.353(1) degrees , V = 2154.8(2) A3, Z = 4. Crystal data for C56H73Br3N11O18.50 Re2 (3(2).NEt4Br . 8.5H2O): monoclinic, C2/c, a = 34.7760(19) A, b = 21.1711(12) A, c = 20.3376(11) A, beta = 115.944(1) degrees , V = 13464.5(1) A3, Z = 8. Crystal data for C26H21BrN3O5Re (4): monoclinic, P2(1)/c, a = 16.6504(6) A, b = 10.1564(4) A, c = 14.6954(5) A, beta = 96.739(1) degrees , V = 2467.9(2) A3, Z = 4. Crystal data for C27H24BrN4O5Re (6): monoclinic, P2(1), a = 8.7791(9) A, b = 16.312(2) A, c = 8.9231(9) A, beta = 90.030(1) degrees , V = 1277.8(2) A3, Z = 2.
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Affiliation(s)
- Lihui Wei
- Department of Chemistry, Syracuse University, Syracuse, New York 13244, USA
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Banerjee SR, Babich JW, Zubieta J. A new bifunctional amino acid chelator targeting the glucose transporter. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2005.11.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Vyas TK, Babbar AK, Sharma RK, Singh S, Misra A. Preliminary brain-targeting studies on intranasal mucoadhesive microemulsions of sumatriptan. AAPS PharmSciTech 2006; 7:E49-E57. [PMID: 28290023 PMCID: PMC2750715 DOI: 10.1208/pt070108] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Accepted: 09/14/2005] [Indexed: 11/30/2022] Open
Abstract
The aim of this investigation was to prepare microemulsions containing sumatriptan (ST) and sumatriptan succinate (SS) to accomplish rapid delivery of drug to the brain in acute attacks of migraine and perform comparative in vivo evaluation in rats. Sumatriptan microemulsions (SME)/sumatriptan succinate microemulsions (SSME) were prepared using titration method and characterized for drug content, globule size and size distribution, and zeta potential. Biodistribution of SME, SSME, sumatriptan solution (SSS), and marketed product (SMP) in the brain and blood of Swiss albino rats following intranasal and intravenous (IV) administrations were examined using optimized technetium-labeled (99mTc-labeled) ST formulations. The pharmacokinetic parameters, drug targeting efficiency (DTE), and direct drug transport (DTP) were derived. Gamma scintigraphy imaging of rat brain following IV and intranasal administrations were performed to ascertain the localization of drug. SME and SSME were transparent and stable with mean globule size 38±20 nm and zeta potential between -35 to -55 mV. Brain/blood uptake ratios at 0.5 hour following IV administration of SME and intranasal administrations of SME, SMME, and SSS were found to be 0.20, 0.50, 0.60, and 0.26, respectively, suggesting effective transport of drug following intranasal administration of microemulsions. Higher DTE and DTP for mucoadhesive microemulsions indicated more effective targeting following intranasal administration and best brain targeting of ST from mucoadhesive microemulsions. Rat brain scintigraphy endorsed higher uptake of ST into the brain. Studies conclusively demonstrated rapid and larger extent of transport of microemulsion of ST compared with microemulsion of SS, SMP, and SSS into the rat brain. Hence, intranasal delivery of ST microemulsion developed in this investigation can play a promising role in the treatment of acute attacks of migraine.
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Affiliation(s)
- Tushar K Vyas
- Pharmacy Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Kalabhavan, Kalabhavan, Post Box No. 51, 390 001, Vadodara, Gujarat, India
| | - A K Babbar
- Government of India, Ministry of Defense, Institute of Nuclear Medicine and Allied Sciences, Brig S. K. Mazumdar Marg, Timarpur, 110054, Delhi, India
| | - R K Sharma
- Government of India, Ministry of Defense, Institute of Nuclear Medicine and Allied Sciences, Brig S. K. Mazumdar Marg, Timarpur, 110054, Delhi, India
| | - Shashi Singh
- Center for Cellular and Molecular Biology (CCMB), Uppal Road, 500 007, Hyderabad, A. P., India
| | - Ambikanandan Misra
- Pharmacy Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Kalabhavan, Kalabhavan, Post Box No. 51, 390 001, Vadodara, Gujarat, India.
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Vyas TK, Babbar AK, Sharma RK, Singh S, Misra A. Intranasal Mucoadhesive Microemulsions of Clonazepam: Preliminary Studies on Brain Targeting. J Pharm Sci 2006; 95:570-80. [PMID: 16419051 DOI: 10.1002/jps.20480] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of this investigation was to prepare clonazepam microemulsions (CME) for rapid drug delivery to the brain to treat acute status epileptic patients and to characterize and evaluate the performance of CME in vitro and in vivo in rats. The CME were prepared by the titration method and were characterized for globule size and size distribution, zeta potential, and drug content. CME was radiolabeled with (99m)Tc (technetium) and biodistribution of drug in the brain was studied in Swiss albino rats after intranasal and intravenous administrations. Brain scintigraphy imaging in rabbits was also performed to ascertain the uptake of the drug into the brain. Pre and postCME formulation treated human nasal mucosa was subjected to transmission electron microscopy to investigate the mechanism of drug uptake across the nasal mucosa. CME were transparent and stable with mean globule size of 15 +/- 10 nm and zeta potential of -30 mV to -40 mV. (99m)Tc-labeled clonazepam solution ((99m)Tc CS)/ clonazepam microemulsion (CME)/clonazepam mucoadhesive microemulsion (CMME) were found to be stable and suitable for in vivo studies. Brain/blood uptake ratios at 0.50 hour (h) following intranasal CMME, CME, clonazepam solution (CS), and intravenous CME administrations were found to be 0.67, 0.50, 0.48, and 0.13, respectively indicating more effective targeting with intranasal administration and best targeting of the brain with intranasal CMME. Brain/blood ratio at all sampling points up to 8 h following intranasal administration of CMME compared to intravenous was found to be twofold higher indicating larger extent of distribution of the drug in brain. Rabbit brain scintigraphy also showed higher intranasal uptake of the drug into the brain. Transmission electron microscopy revealed significant accretion of CMME within interstitial spaces and paracellular mode of transport due to stretching of the tight junctions present in the nasal mucosa. This investigation demonstrates a more rapid and larger extent of transport of clonazepam into the rat brain with intranasal CMME, which may prove useful in treating acute status epileptics.
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Affiliation(s)
- Tushar K Vyas
- Pharmacy Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Kalabhavan, Vadodara, Gujarat, India
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Stephenson KA, Banerjee SR, McFarlane N, Boreham DR, Maresca KP, Babich JW, Zubieta J, Valliant JF. A convenient solid-phase synthesis methodology for preparing peptide-derived molecular imaging agents Synthesis, characterization, and in vitro screening of Tc(I) chemotactic peptide conjugates. CAN J CHEM 2005. [DOI: 10.1139/v05-224] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A versatile solid-phase synthesis strategy for preparing peptidechelate conjugates was developed. The methodology was optimized using a series of ligands, designed to bind Tc(I)/Re(I), and a chemotactic peptide fMFL, which was exploited as a model targeting vector. The peptide derivatives were prepared in parallel using a conventional automated peptide synthesizer in multi-milligram quantities, which provided sufficient material to perform complete characterization, radiolabelling, and in vitro screening studies. Because of the robust nature of the metalchelate complexes, the Re complex of a chelatepeptide conjugate was prepared on the resin using the same methodology employed to prepare the free ligand conjugates. As such, the reported methodology is amenable to the preparation of libraries of novel Tc radiopharmaceutical ligands and their corresponding Re reference standards in which several factors, including peptide sequence, site of derivatization, and both the type and length of the spacer, can be easily varied.Key words: radiopharmaceuticals, technetium, rhenium, peptides, solid-phase synthesis.
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Wei L, Babich J, Zubieta J. Bifunctional chelates with mixed aromatic and aliphatic amine donors for labeling of biomolecules with the {Tc(CO)3}+ and {Re(CO)3}+ cores. Inorganica Chim Acta 2005. [DOI: 10.1016/j.ica.2005.04.039] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Mishra AK, Chopra M, Jain V. Convenient Route for Synthesis of Bifunctional Chelating Agent: 1-(p-Aminobenzyl)ethylenediaminetetramethylphosphonic acid–Folate Conjugate (Am-Bz-EDTMP–Folate). CHEM LETT 2005. [DOI: 10.1246/cl.2005.1098] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Banerjee SR, Maresca KP, Francesconi L, Valliant J, Babich JW, Zubieta J. New directions in the coordination chemistry of 99mTc: a reflection on technetium core structures and a strategy for new chelate design. Nucl Med Biol 2005; 32:1-20. [PMID: 15691657 DOI: 10.1016/j.nucmedbio.2004.09.001] [Citation(s) in RCA: 153] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Revised: 08/31/2004] [Accepted: 09/01/2004] [Indexed: 11/26/2022]
Abstract
Bifunctional chelates offer a general approach for the linking of radioactive metal cations to macromolecules. In the specific case of 99mTc, a variety of technologies have been developed for assembling a metal-chelate-biomolecule complex. An evaluation of these methodologies requires an appreciation of the coordination characteristics and preferences of the technetium core structures and oxidation states, which serve as platforms for the development of the imaging agent. Three technologies, namely, the MAG3-based bifunctional chelates, the N-oxysuccinimidylhydrazino-nicotinamide system and the recently described single amino acid chelates for the {Tc(CO)3}1+ core, are discussed in terms of the fundamental coordination chemistry of the technetium core structures. In assessing the advantages and disadvantages of these technologies, we conclude that the single amino acid analogue chelates (SAAC), which are readily conjugated to small peptides by solid-phase synthesis methods and which form robust complexes with the {Tc(CO)3}1+ core, offer an effective alternative to the previously described methods.
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Affiliation(s)
- Sangeeta Ray Banerjee
- Department of Chemistry, Syracuse University, Center for Science and Technology, Syracuse, NY 13244, USA
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Banerjee SR, Maresca KP, Stephenson KA, Valliant JF, Babich JW, Graham WA, Barzana M, Dong Q, Fischman AJ, Zubieta J. N,N-Bis(2-mercaptoethyl)methylamine: A New Coligand for Tc-99m Labeling of Hydrazinonicotinamide Peptides. Bioconjug Chem 2005; 16:885-902. [PMID: 16029030 DOI: 10.1021/bc050040y] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydrazinonicotinamide (HYNIC) forms stable coordination complexes with Tc-99m when reacted with Tc(V)oxo species such as Tc-mannitol or other Tc-polyhydric complexes. However, radio-HPLC of [Tc-For-MLFK-HYNIC] labeled via Tc-polyhydric ligands demonstrated multiple radiochemical species each with unique biodistribution patterns. This is likely due to the fact that Tc can bind to the hydrazino moiety, as well as polyhydric ligands, in a variety of coordination geometries. Tridentate ligands, such as bis(mercaptoethyl)methylamine (NS2), may constrain the possible coordination geometries and improve overall stability. To investigate this, we synthesized NS2, converted the [Tc-mannitol-For-MLFK-HYNIC] to the corresponding NS2-containing complex [Tc-NS2-For-MLFK-HYNIC], and compared its infection imaging and biodistribution properties with [Tc-mannitol-For-MLFK-HYNIC]. Conversion to the NS2 complex was confirmed by HPLC which showed a single unique hydrophobic species with retention time greater than the [Tc-mannitol-For-MLFK-HYNIC] complex. Imaging experiments with both preparations were performed in rabbits with E. coli infections in the left thigh. Tissue radioactivity measurements demonstrated that compared to Tc-mannitol-peptide, accumulation of Tc-NS2-peptide was lower in blood, heart, and normal muscle and higher in spleen, infected muscle, and pus (p < 0.01). These results indicate that the Tc-NS2-peptide complex is chemically more homogeneous and exhibits improved infection localization and biodistribution properties. In an effort to model the interactions of the metal-HYNIC core with NS2 and related ligand types, the reactions of [ReCl3(NNC5H4NH)(NHNC5H4N)] and [99TcCl3(NNC5H4NH)(NHNC5H4N)], effective structural analogues for the [M(NNC5H4NH(x))2] core, with NS2, C5H3N-2,6-(CH2SH)2, O(CH2CH2SH)2, and S(CH2CH2SH)2 were investigated and the compounds [M[CH3N(CH2CH2S)2](NNC5H4N)(NHNC5H4N] (M = 99Tc (5a), Re (5b)), [Re[C5H3N-2,6-(CH2S)2](NNC5H4N)(NHNC5H4N)].CH2Cl2.0.5MeOH (7), [Re[SCH2CH2)2O] (NNC5H4N)(NHNC5H4N)] (8), and [Re[(SCH2CH2)2S](NNC5H4NH)(NHNC5H4N)]Cl (9) were isolated. Similarly, the reaction of [ReCl3(NNC5H4NH)(NHNC5H4N)] with the bidentate ligands pyridine-2-methanethiol and 3-(trimethlysilyl)pyridine-2-thiol led to the isolation of [ReCl(C5H4N-2-CH2S) (NNC5H4N)(NHNC5H4N)] (10) and [Re(2-SC5H3N-3-SiMe3)2 (NNC5H4N)(NHNC5H4N)] (11), respectively, while reaction with N-methylimidazole-2-thiol yielded the binuclear complex [Re(OH)Cl(SC3H2N2CH3)2(NNC5H4N)2 (NHNC5H4N)2] (12). The analogous metal-(HYNIC-OH) precursor, [ReCl3[NNC5H3NH(CO2R)] [NHNC5H3N(CO2R)]] (R = H, 13a; R = CH3, 13b) has been prepared and coupled to lysine to provide [RCl3[NNC5H3NH(CONHCH2CH2CH2CH2CH(NH2)CO2H)] [NHNC5H3NH(CONHCH2CH2CH2CH2CH(NH2)CO2H)]].2HCl (14.2HCl), while the reaction of the methyl ester 13b with 2-mercaptopyridine yields [Re(2-SC5H4N)2[NNC5H3N(CO2Me)][NHNC5H3N(CO2Me)]] (15). While the chemical studies confirm the robustness of the M-HYNIC core (M = Tc, Re) and its persistence in ligand substitution reactions at adjacent coordination sites of the metal, the isolation of oligomeric structures and the insolubility of the peptide conjugates of 13, 14, and 15 underscore the difficulty of characterizing these materials on the macroscopic scale, an observation relevant to the persistent concerns with reagent purity and identity on the tracer level.
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Awasthi V, Meinken G, Springer K, Srivastava SC, Freimuth P. Biodistribution of radioiodinated adenovirus fiber protein knob domain after intravenous injection in mice. J Virol 2004; 78:6431-8. [PMID: 15163736 PMCID: PMC416552 DOI: 10.1128/jvi.78.12.6431-6438.2004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The knob domains from the fiber proteins of adenovirus serotypes 2 and 12 were labeled with radioiodine and then injected into the bloodstreams of mice. Knob proteins with functional binding sites for the coxsackie and adenovirus receptor (CAR) were cleared rapidly from the circulation, with radioactivity appearing predominantly in the stomach, while knob mutants unable to bind to CAR remained in the blood circulation for a prolonged period. The clearance of radiolabeled wild-type knob from the blood was slowed by coinjecting an excess of unlabeled wild-type knob protein. An earlier study showed that (99m)Tc-labeled knob protein with intact CAR-binding activity also cleared rapidly from the blood circulation of mice, with radioactivity accumulating predominantly in the liver (K. R. Zinn et al., Gene Ther. 5:798-808, 1998). Together these results suggest that rapid clearance of knob protein from the blood results from specific binding to CAR in the liver and that the bound knob then enters a degradative pathway. The elevated levels of radioiodine in the stomach observed in our experiments are consistent with deiodination of labeled knob by dehalogenases in hepatocyte microsomes and uptake of the resultant free radioiodine by Na/I symporters in the gastric mucosa. Although CAR has been shown to localize in tight junctions of polarized epithelial cells, where it functions in intercellular adhesion, the results of our study suggest that a subset of CAR molecules in the liver is highly accessible to ligands in the blood and able to rapidly deliver bound ligand to an intracellular degradative compartment.
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Affiliation(s)
- Vibhudutta Awasthi
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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