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In this study Isoniazid (INH) as one of the first line drugs in treatment of Tuberculosis was investigated to be loaded in Solid Lipid Nanoparticles (SLNs) for reducing hepatotoxicity as well as prolonging drug release. High shear homogenization method was performed to prepare INH SLNs. To compare biodistribution of INH before and after loading in SLNs, INH was labeled by Technetium 99 (Tc99) after derivatization. The particle size of the prepared SLNs was 167 and 200 nm before and after lyophilization, respectively. Loading efficiency was calculated using the reverse method and release study was performed by using the dialysis sack method. Loading efficiency was 98%, and more than 85% of the loaded drug released in 3 h. Differential Scanning calorimeter (DSC) studies were performed for evaluating of the probability of happening hydrogen bonds or other chemical interactions between cholesterol as carrier and isoniazid as active pharmaceutical ingredient. The results could support the probability of hydrogen bond formation between cholesterol and INH. Gamma Scintigraphy studies showed that after administering INH SLNs, longer drug retention in the body was obtained compared to free INH. Quantitative gamma counting showed that the concentration of INH in the liver and intestines could be decreased by using nanotechnology.
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99mTc-Macroaggregated Albumin (99mTc-MAA) has been used as a perfusion agent. This study described development of the 68Ga-MAA via commercially available kits from Pars-Isotopes Company as a 99mTc-MAA kit. 68Ge/68Ga generator was eluted with suprapure HCl (0.6â M, 6â mL) in 0.5â mL fractions. The two fractions with the highest 68GaCl3 activity were generally used for labeling purposes. After labeling, the final product was centrifuged 2 times to purify the solution. Five rats were sacrificed at each exact time interval (from 15 min to 2 h post injection) and the percentage of injected dose per gram (%ID/g) of each organ was measured by direct counting from 11 harvested organs of rats. The RTLC showed that labeling yields before centrifuges were 90% and 95% for Pars-Isotopes and GE kits, respectively and after centrifuges, they became 100%. The microscopic size examination showed a shift in the particle sizes post centrifuges and the biodistribution data revealed the efficiency and benefits of centrifuges in terms of preventing the of liver and bone marrow uptakes especially for Pars-Isotopes kits. Our results showed that after centrifuges of the final product, the lung uptakes increased from 89% to more than 97% of %ID/g after 5 min post injections. The whole procedure took less than 25 min from elution to the ï¬nal product. Since 99mTc-MAA remained longer than 68Ga-MAA in the lung and 68Ga-MAA showed better image qualities, using 68Ga-MAA is recommended.
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Nanotechnology has been used for every single modality in the molecular imaging arena for imaging purposes. Synergic advantages can be explored when multiple molecular imaging modalities are combined with respect to single imaging modalities. Multifunctional nanoparticles have large surface areas, where multiple functional moieties can be incorporated, including ligands for site-specific targeting and radionuclides, which can be detected to create 3D images. Recently, radiolabeled nanoparticles with individual properties have attracted great interest regarding their use in multimodality tumor imaging. Multifunctional nanoparticles can combine diagnostic and therapeutic capabilities for both target-specific diagnosis and the treatment of a given disease. The future of nanomedicine lies in multifunctional nanoplatforms that combine the diagnostic ability and therapeutic effects using appropriate ligands, drugs, responses and technological devices, which together are collectively called theranostic drugs. Co-delivery of radiolabeled nanoparticles is useful in multifunctional molecular imaging areas because it comprises several advantages based on nanoparticles architecture, pharmacokinetics and pharmacodynamic properties.
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Nanopartículas/administración & dosificación , Neoplasias/diagnóstico , Radiofármacos/administración & dosificación , Animales , Humanos , Imagen Molecular/métodos , Nanomedicina/métodos , Nanotecnología/métodosRESUMEN
In this review, we emphasize the efforts on the development of radiolabeled nanoparticles (NPs) for cancer treatment, i.e. theranostic tools based on nanotechnology and nuclear medicine. Currently, radionuclide therapy remains to be an important treatment option. The ionizing radiation from radionuclides (not provided by drugs) can kill cells or inhibit the growth in the periphery and the inaccessible center of cancerous lesions. Sites of damage comprise all cellular levels, especially DNA in the nucleus of cells. In addition, recent developments in nanotechnology have made it possible to conjugate NPs to biological moieties for targeted therapy. This enables the more specific radiation dose delivery, preventing damage to healthy tissues. Before the introduction of these NPs-based radionuclide therapies in clinical practice, it is necessary perform investigations to demonstrate dosage-accurate radiation delivery, biocompatibility, pharmacokinetic/pharmacodynamic parameters and risk/benefit evaluations. Because of these issues, a transition to clinical trials is difficult. The properties of NPs make it possible to build theranostic devices with targeting and regulatory mechanisms offered by biological effectors against cancer.
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Nanopartículas/uso terapéutico , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Radiofármacos/clasificación , Radiofármacos/uso terapéutico , Animales , Sistemas de Liberación de Medicamentos/métodos , Humanos , CintigrafíaRESUMEN
Even in recent decades, one of the major causes of death and unhealthiness in the whole world is infection and inflammation. The use of radiopharmaceuticals is a powerful tool in managing the patients with infectious diseases. In this study, ofloxacin as a second-generation fluoroquinolone has been labeled with [(99m) Tc(CO)3 (H2 O)3 ](+) core to formulate a suitable infection imaging agent. Ofloxacin was radiolabeled with (99m) Tc using carbonyl core. Radioligand chemical analysis involved HPLC methods. Radioconjugate stability and lipophilicity were determined. Binding with Staphylococcus aureus and biodistribution in infected mice for labeled compound were studied. The radioligand was characterized by HPLC, and its radiochemical purity was more than 90%. In vitro stability studies have shown the complex was stable at least 6 h after labeling at room temperature. The n-octanol/water partition coefficient experiment exhibited logP = 1.52 ± 0.21 for (99m) Tc(CO)3 -ofloxacin. The complex showed specific binding to S. aureus. Biodistribution results showed that radioligand had high accumulation in the infected muscle in a mice (T/NT = 2.02 ± 0.12 at 4 h postinjection). On the basis of stability and infection site uptake ratio, suitability of this complex as a radiotracer for imaging of infections is recognized.