Imaging of Clot by Tc-HMPAO Labeled Platelet in Animal Model Induced Thrombosis.

Tc-HMPAO labeled platelet (LP) imaging may integrate thrombosis imaging into routine clinical procedures. In the current study, we assessed the feasibility of the use of Tc-HMPAO LP for imaging of small clots in an animal model. Thrombosis was induced by application of FeCl solution in the distal part of the inferior vena cava (IVC) of a 6100 g anesthetized rabbit and in a male Wistar rat weighing 420 g.

Preclinical evaluation of new GnRH-I receptor radionuclide therapy with Lu-peptide tracer.

The purpose of this study was to develop preclinical evaluation of a novel radiolabeled gonadotropin-releasing hormone (GnRH) receptor targeting peptide for prostate cancer therapy. The new antiproliferative agent of GnRH-I analogue was developed on the basis of the D-Trp -GnRH-I scaffold, and in vivo pharmacokinetics and receptor binding affinity were enhanced by the substitution of Gly-NHNH for Gly-NH at position 10 in D-Trp -GnRH-I. To evaluate Lu-DOTA-triptorelin-hydrazide as radionuclide therapy of tumor, the quality control tests and preclinical stage assessment were carried out.

Radiolabeling of Preformed Niosomes with [Tc]: In Vitro Stability, Biodistribution, and In Vivo Performance.

Nanocarriers radiolabeled with [Tc] can be used for diagnostic imaging and radionuclide therapy, as well as tracking their pharmacokinetic and biodistribution characteristics. Due to the advantages of niosomes as an ideal drug delivery system, in this study, the radiolabeling procedure of niosomes by [Tc]-HMPAO complexes was investigated and optimized. Glutathione (GSH)-loaded niosomes were prepared using a thin-film hydration method.

Development of Dendrimer Encapsulated Radio-Ytterbium and Biodistributionin Tumor Bearing Mice.

The aim of this study is preparation of dendrimer encapsulated ytterbium-175 radio-nanoparticles and investigation of the compound chemical characteristic before and after the neutron irradiation and also study the in vivo biodistribution for targeted radiopharmaceutical dose delivery to solid tumors. For preparation of dendrimer-metal nanocomposite, a dendrimer compound containing an average of 55 Yb ions per dendrimer was prepared. The synthesized encapsulated ytterbium irradiated by neutron for 2 h at 3×10 n.

Preparation, Biological Evaluation and Dosimetry Studies of 175Yb-Bis-Phosphonates for Palliative Treatment of Bone Pain.

Objective: Optimized production and quality control of ytterbium-175 (Yb-175) labeled pamidronate and alendronate complexes as efficient agents for bone pain palliation has been presented.

Methods: Yb-175 labeled pamidronate and alendronate (175Yb-PMD and 175Yb-ALN) complexes were prepared successfully at optimized conditions with acceptable radiochemical purity, stability and significant hydroxyapatite absorption. The biodistribution of complexes were evaluated up to 48 h, which demonstrated significant bone uptake ratios for 175Yb-PAM at all-time intervals.

Preparation and Biological Study of (68)Ga-DOTA-alendronate.

Objectives: In line with previous research on the development of conjugated bisphosphonate ligands as new bone-avid agents, in this study, DOTA-conjugated alendronate (DOTA-ALN) was synthesized and evaluated after labeling with gallium-68 ((68)Ga).

Methods: DOTA-ALN was synthesized and characterized, followed by (68)Ga-DOTA-ALN preparation, using DOTA-ALN and (68)GaCl3 (pH: 4-5) at 92-95° C for 10 min. Stability tests, hydroxyapatite assay, partition coefficient calculation, biodistribution studies, and imaging were performed on the developed agent in normal rats.

Development of a (68)Ga-peptide tracer for PET GnRH1-imaging.

Objective: Total synthesis, quality control and preclinical evaluation of [(68)Ga]-DOTA-triptorelin ([(68)Ga]-DOTA-TRP) is reported as a possible PET radiotracer for GnRH receptor imaging.

Methods: DOTA-TRP was totally synthesized in two steps and after characterization went through radiolabelling optimization studies followed by tracer stability. The biodistribution of the tracer in normal male rats and 4T1 tumour-bearing mice was performed in 120 min after i.

Effect of coating thickness of iron oxide nanoparticles on their relaxivity in the MRI.

Objectives: Iron oxide nanoparticles have found prevalent applications in various fields including drug delivery, cell separation and as contrast agents. Super paramagnetic iron oxide (SPIO) nanoparticles allow researchers and clinicians to enhance the tissue contrast of an area of interest by increasing the relaxation rate of water. In this study, we evaluate the dependency of hydrodynamic size of iron oxide nanoparticles coated with Polyethylene glycol (PEG) on their relativities with 3 Tesla clinical MRI.

Nano Liposomes Labeled with (99m)Tc-HMPAO, a Novel Agent for Blood Pool Imaging.

In-vitro labeling of RBC with (99m)Tc is an intricate procedure and there is always a need for an alternate blood pool imaging agent. The aim of this study was to prepare an effective nano sized liposome (NLs) similar to human RBC for blood pool scintigraphy. This study formulates PEG-NLs and non-PEG-NLs using film method plus high pressure homogenization technique.

Development of (153) Sm-folate-polyethyleneimine-conjugated chitosan nanoparticles for targeted therapy.

The aim of this study was to develop biocompatible, water-soluble (153) Sm-labeled chitosan nanoparticles (NPs) containing folate and polyethyleneimine functionalities i.e. chitosan-graft-PEI-folate (CHI-DTPA-g-PEI-FA), suitable for targeted therapy.

Activity estimation in radioimmunotherapy using magnetic nanoparticles.

Objective: Estimation of activity accumulated in tumor and organs is very important in predicting the response of radiopharmaceuticals treatment. In this study, we synthesized (177)Lutetium ((177)Lu)-trastuzumab-iron oxide nanoparticles as a double radiopharmaceutical agent for treatment and better estimation of organ activity in a new way by magnetic resonance imaging (MRI).

Methods: (177)Lu-trastuzumab-iron oxide nanoparticles were synthesized and all the quality control tests such as labeling yield, nanoparticle size determination, stability in buffer and blood serum up to 4 d, immunoreactivity and biodistribution in normal mice were determined.

Synthesis and preliminary evaluation of a new (99m)tc labeled substance p analogue as a potential tumor imaging agent.

Neurokinin 1 receptors (NK1R) are overexpressed on several types of important human cancer cells. Substance P (SP) is the most specific endogenous ligand known for NK1Rs. Accordingly,a new SP analogue was synthesized and evaluated for detection of NK1R positive tumors.

Monoclonal antibody conjugated magnetic nanoparticles could target MUC-1-positive cells in vitro but not in vivo.

MUC1 antigen is recognized as a high-molecular-weight glycoprotein that is unexpectedly over-expressed in human breast and other carcinomas. In contrast, C595 a monoclonal antibody (mAb) against the protein core of the human urinary epithelial machine, is commonly expressed in breast carcinomas. The aim of this study was to conjugate ultra-small super paramagnetic iron oxide nanoparticles (USPIO) with C595 mAb, in order to detect in vivo MUC1 expression.

Preparation and radiolabeling of a lyophilized (kit) formulation of DOTA-rituximab with ⁹⁰Y and ¹¹¹In for domestic radioimmunotherapy and radioscintigraphy of non-Hodgkin's lymphoma.

Background: On the basis of results of our previous investigations on 90Y-DTPA-rituximab and in order to fulfil national demands to radioimmunoconjugates for radioscintigraphy and radioimmunotherapy of Non-Hodgkin's Lymphoma (NHL), preparation and radiolabeling of a lyophilized formulation (kit) of DOTA-rituximab with 111In and 90Y was investigated.

Methods: 111In and 90Y with high radiochemical and radionuclide purity were prepared by 112Cd (p,2n)111In nuclear reaction and a locally developed 90Sr/90Y generator, respectively. DOTA-rituximab immunoconjugates were prepared by the reaction of solutions of p-SCN-Bz-DOTA and rituximab in carbonate buffer (pH = 9.

Synthesis, Radiolabeling and Biological Evaluation of (99m)Tc-labeled Deoxyglucose Derivatives for Molecular Imaging.

Two deoxyglucose (DG) derivatives, (α,β)-2-deoxy-2-amino(ethylcarbamate)-D-glucose (ECB-DG) and (α,β)-2-deoxy-2-amino(1,2-dihydroxypropyl)-D-glucose (DHP-DG), were synthesized and radiolabeled successfully with [(99m)Tc(H2O)3(CO)3](+) complex. [(99m)Tc]-ECB-DG and [(99m)Tc]-DHP-DG complexes were prepared (96% and 93% radiochemical purities respectively) by using 46 mCi of Na(99m)TcO4 in 1 mL saline. Radio-HPLC analysis of [(99m)Tc]- ECB-DG at pH = 7.

Synthesis and receptor binding studies of novel 4,4-disubstituted arylalkyl/arylalkylsulfonyl piperazine and piperidine-based derivatives as a new class of σ1 ligands.

This study presents the synthesis and biological evaluation of a new series of arylalkyl/arylalkylsulfonyl piperazine and piperidine-based derivatives as sigma receptor ligands. It was found that a number of halogen substituted sulfonamides display relatively high and low affinities to σ1 and σ2 receptors, respectively. The σ1 affinities and subtype selectivities of four piperidine derivatives were also found to be generally comparable to those of piperazine analogues.

Evaluating the effect of ultrasmall superparamagnetic iron oxide nanoparticles for a long-term magnetic cell labeling.

In order to evaluate the long-term viability, the iron content stability, and the labeling efficiency of mammalian cells using magnetic cell labeling; dextran-coated ultrasmall superparamagnetic iron oxide (USPIOs) nanoparticles with plain surfaces having a hydrodynamic size of 25 nm were used for this study. Tests were carried out in four groups each containing 5 flasks of 5.5 × 10(6) AD-293 embryonic kidney cells.

Comparison of (99m)Tc-labeled PR81 and its F(ab')₂ fragments as radioimmunoscintigraphy agents for breast cancer imaging.

Objective: We digested anti-MUC1 monoclonal antibody PR81 to produce F(ab')₂ fragments. A comparison was performed between the two radiolabeled PR81 and F(ab')₂ fragments for breast tumor imaging in a mouse model.

Methods: The optimum conditions for pepsin digestion of PR81 were investigated in terms of enzymes: antibody ratio, digestion time duration and preserved immunoreactivity of the produced fragments.

177Lu labeling of Herceptin and preclinical validation as a new radiopharmaceutical for radioimmunotherapy of breast cancer.

Introduction: In the present study, Herceptin was labeled with lutetium-177 via DOTA, and the necessary preclinical quality control tests (in vitro and in vivo) were performed to evaluate its use as a radioimmunotherapy agent.

Material And Methods: Herceptin was conjugated to DOTA as a chelator in three different conjugation buffers (ammonium acetate, carbonate and HEPES buffer); each of the resulting conjugates was compared with respect to in vitro characteristics such as number of chelates per antibody, incorporated activity, immunoreactivity and in vitro stability in PBS buffer and blood serum. The biodistribution study and gamma camera imaging were performed in mice bearing breast tumors.

Toxicity of trastuzumab labeled 177Lu on MCF7 and SKBr3 cell lines.

In this study, we labeled trastuzumab with (177)Lu to synthesize a new radiopharmaceutical for therapy of breast cancer and at the first stage investigated its therapeutic effects on SKBr3 and MCF7 breast cancer cell lines. Trastuzumab-(177)Lu showed very good in-vitro characteristics such as high radiochemical purity (91+/-0.9%), good stability in PBS buffer (86+/-2.

Radiolabeling of trastuzumab with 177Lu via DOTA, a new radiopharmaceutical for radioimmunotherapy of breast cancer.

Aim: Trastuzumab is a monoclonal antibody that is used in treating breast cancer. We labeled this monoclonal antibody with lutetium-177 and performed in vitro quality control tests as a first step in the production of a new radiopharmaceutical.

Material And Methods: Trastuzumab was labeled with lutetium-177 using DOTA as chelator.

99mTc-HMPAO-labeled liposomes: an investigation into the effects of some formulation factors on labeling efficiency and in vitro stability.

Technetium-99m complex of hexamethyl-propylene-amineoxime (HMPAO) is used as an efficient agent to label liposomes. For this, 99mTc-HMPAO is incubated with preformed liposomes that contain glutathione (GSH). Effect of GSH and lipid concentration on labeling efficiency, as well as the effect of lipid composition on in vitro stability of labeled liposomes, was investigated in the present study.

Synthesis of carbon-14 analogue of 1,5 diaryl-5-[14C]-1,2,3-triazoles.

Two 1,2,3-triazole anticonvulsants, 1-(4-methylsulfone-phenyl)-5-(4-methyl-phenyl)-1,2,3-triazole and 1-(4-methylsulfone-phenyl)-5-phenyl-1,2,3-triazole, both labeled with carbon-14 in the 5-position were prepared from para-tolunitrile-[cyano-14C] and benzonitrile-[cyano-14C], respectively.