68 Ga-labeled, imatinib encapsulated, theranostic liposomes: Formulation, characterization, and in vitro evaluation of anticancer activity.

Cancer is still a global health problem. Among cancer types, breast cancer is the most frequently diagnosed one, and it causes a high mortality rate if not diagnosed in the early stages. In our study, imatinib encapsulated, nanosized, neutral/cationic liposome formulations were prepared as theranostic agents for breast cancer. After the characterization studies in which all liposomes exhibited proper profile owing to their particle size between 133 and 250 nm, polydispersity index values lower than 0.4, neutral and cationic zeta potential values, and high drug encapsulation efficiency, controlled drug release behaviors with zero-order kinetic were obtained. The higher than 90% radiolabeling efficiency values were obtained thanks to the determination of optimum radiolabeling condition (80°C temperature, 5 mCi radioactivity, and 10 min incubation period). According to the resazurin assay evaluating the cytotoxic profile of liposomes on MCF7 cells, neutral empty liposome was found as biocompatible, while both cationic liposomes (empty and drug-loaded ones) exhibited high nonspecific cytotoxicity at even low drug concentration due to the existence of stearyl amine in the formulations. However, dose-dependent cytotoxic effect and the highest cellular binding capacity were obtained by imatinib loaded neutral liposomes. In conclusion, 68 Ga-radiolabeled, imatinib-loaded, neutral, nanosized liposome formulation is the most promising one as a theranostic agent among all formulations.

Radiolabeling, Quality Control, and Cell Binding Studies of New 99mTc-Labeled Bisphosphonates: 99mTc-Ibandronate Sodium.

Objectives: Early detection of bone cancer is critical for treating symptoms, minimizing pain, and increasing overall quality of life. It is critical to develop novel radiopharmaceuticals with high labeling efficiency and stability for the diagnosis of bone cancer. This research aims to design a novel radiopharmaceutical that may be used to diagnose bone cancer. Materials and Methods: In this study, ibandronate sodium (IBD), a bisphosphonate analog, was radiolabeled with technetium-99m [99mTc] and quality control tests on the newly developed radiopharmaceutical ([99mTc]Tc-IBD) were performed using radioactive thin layer chromatography. After that, the incorporation of [99mTc]Tc-IBD into hydroxyapatite (HA) crystals and a human bone osteosarcoma cell line (U2OS) was tested. Results: According to the results obtained, optimal radiolabeling procedure was obtained for [99mTc]Tc-IBD with 200 µg.mL-1 IBD, 20 µg stannous chloride, and 99mTc with 37 MBq radioactivity. The reaction mixture was adjusted to pH 5.5 and incubated at room temperature for 15 min. The radiochemical purity of [99mTc]Tc-IBD was found to be greater than 95% at room temperature for up to 6 h. Additionally, chromatography analysis showed >95% [99mTc]Tc-IBD complex formation with promising stability for up to 24 h in saline and up to 2 h in cell medium. The percentage binding of IBD to HA was 83.70 ± 3.67 and the logP of [99mTc]Tc-IBD was -1.1014. The radiolabeled complex exhibited a higher rate of cell incorporation to U2OS cells compared to Reduced/Hydrolyzed 99mTcO4 -. Conclusion: The newly produced radiopharmaceutical is very promising according to the results of in vitro cell culture, HA binding, and quality studies, and will be a step forward for further studies in nuclear medicine for bone cancer diagnostics.

99mTc-Labeled, Colistin Encapsulated, Theranostic Liposomes for Pseudomonas aeruginosa Infection.

Infectious diseases are still the major issue not only due to antibiotic resistance but also causing deaths if not diagnosed at early-stages. Different approaches including nanosized drug delivery systems and theranostics are researched to overcome antibiotic resistance, decrease the side effects of antibiotics, improve the treatment response, and early diagnose. Therefore, in the present study, nanosized, radiolabeled with 99mTc, colistin encapsulated, neutral and cationic liposome formulations were prepared as the theranostic agent for Pseudomonas aeruginosa infections. Liposomes exhibited appropriate physicochemical properties thanks to their nano-particle size (between 173 and 217 nm), neutral zeta potential value (about - 6.5 and 2.8 mV), as well as encapsulation efficiency of about 75%. All liposome formulations were radiolabeled with over 90% efficiency, and the concentration of stannous chloride was found as 1 mg.mL-1 to obtain maximum radiolabeling efficiency. In alamar blue analysis, neutral liposome formulations were found more biocompatible compared with the cationic formulations. Neutral colistin encapsulated liposomes were found to be more effective against P. aeruginosa strain according to their time-dependent antibacterial effect, in addition to their highest bacterial binding capacity. As conclusion, theranostic, nanosized, colistin encapsulated, neutral liposome formulations were found as promising agents for the imaging and treating of P. aeruginosa infections.

Evaluation of F-18 FDG radiopharmaceuticals through Molecular Docking and radiation effects.

Fluorodeoxyglucose (FDG), marked with the most used Positron Emission Tomography (PET) radiopharmaceutical Fluorine-18 (F-18), is a glucose analog and is taken to living cells through membrane glucose carriers. F-18 FDG involvement in tissue is proportional to glucose use. In many cancers, there is increased glucose use due to increased gluten expression and hexokinase activity. F-18 FDG PET is a proven method for diagnosis, staging, re-staging, and evaluation of treatment response in oncology. The purpose of this study is to find the effect of ionizing radiation on proteins in the mechanism of action of FDG and determine to Molecular mechanisms of F-18 FDG accumulation in metabolism. In the study, two different models were used together, the first method, the study was Molecular Docking method for modeling molecules deconstructed and the structure of FDG was energy minimized by utilizing the density functional theory, and the B3LYP functional was used with 6-311G basis set. The second method was the Monte Carlo method for modeling ionizing radiation interactive with the potential routes of FDG metabolism within the cell. It was determined that the Gibbs free energy (ΔG) change was compatible with the ionizing radiation factors for binding of FDG to the aphthous regions of Glucose-6-phosphate isomerase (G1), hexokinase (G2), and glucose transporter-1 (G3) were selected. In this study, the strong binding of FDG to protein influences the effect of radiation on the active site of enzymes. The G1 and G3 shown in the study interacted with only one charged amino acid FDG, and the absence of an aromatic residue around it can be considered among the results of this study as the cause of the low protective effect against ionizing radiation.

Polymer based Gels: Recent and Future Applications in Drug Delivery Field.

BACKGROUND: Currently, there is ongoing research in the pharmaceutical technology field to develop innovative drug delivery systems with improved therapeutic efficacy. OBJECTIVES: Although there is a high need for new drug molecules, most scientists focus on the advancement of novel pharmaceutical formulations since the present excipients lack important properties such as low release rate leading to repeated dosing. Aside from this, pharmaceutical technologists aim to develop drug formulations that can target specific organs and tissues, lowering the possibility of adverse effects. METHODS: This review aims to cover the different polymer-based gel types, the development and characterization methods, as well as applications thereof. Finally, the recent advancements and future perspectives focusing on radiolabeled gels will be addressed. RESULTS: In the last decades, polymer based pharmaceutical gels have shown attractive properties and therefore have raised the attention of pharmaceutical scientists. Gels are either chemically or physically cross-linked networks that can absorb fluids such as water (hydrogels), oil (organogels) and even air(aerogels). A variety of polymers, either synthetic or natural, have been employed as components for the gels. Stimuli-responsive gels based on stimuli-sensitive polymers are among the most studied gel class of last years. CONCLUSION: The use of polymer-based gels as drug delivery systems would be beneficial for targeting numerous diseases.

Protein and Gene Delivery Systems for Neurodegenerative Disorders: Where Do We Stand Today?

It has been estimated that every year, millions of people are affected by neurodegenerative disorders, which complicate their lives and their caregivers' lives. To date, there has not been an approved pharmacological approach to provide the complete treatment of neurodegenerative disorders. The only available drugs may only relieve the symptoms or slow down the progression of the disease. The absence of any treatment is quite rational given that neurodegeneration occurs by the progressive loss of the function or structure of the nerve cells of the brain or the peripheral nervous system, which eventually leads to their death either by apoptosis or necrotic cell death. According to a recent study, even though adult brain cells are injured, they can revert to an embryonic state, which may help to restore their function. These interesting findings might open a new path for the development of more efficient therapeutic strategies to combat devastating neurodegenerative disorders. Gene and protein therapies have emerged as a rapidly growing field for various disorders, especially neurodegenerative diseases. Despite these promising therapies, the complete treatment of neurodegenerative disorders has not yet been achieved. Therefore, the aim of this review is to address the most up-to-date data for neurodegenerative diseases, but most importantly, to summarize the available delivery systems incorporating proteins, peptides, and genes that can potentially target such diseases and pass into the blood-brain barrier. The authors highlight the advancements, at present, on delivery based on the carrier, i.e., lipid, polymeric, and inorganic, as well as the recent studies on radiopharmaceutical theranostics.

Radiolabeled Trastuzumab Solid Lipid Nanoparticles for Breast Cancer Cell: in Vitro and in Vivo Studies.

Radiolabeled trastuzumab (TRZ) loaded solid lipid nanoparticles (SLNs) were prepared by high shear homogenization and sonication techniques. The apoptosis mechanism of TRZ-SLNs was studied only with the MCF-7 cell line, while the cytotoxicity and cell binding capacity were investigated using breast cancer cells (MCF-7 and MDA-MB-231) and the human keratinocyte cell line (HaCaT). The particle sizes of TRZ-SLNs were found to be below 100 nm, and they possessed a negative charge. The high radiolabeling efficiency and good radiolabeling stability in saline and a cell culture medium were obtained in the results of radiolabeling studies. According to the in vitro studies, TRZ-SLNs were found to be biocompatible, and they effectively induced apoptosis in MCF-7 cells. After the parenteral injection of TRZ-SLNs into rats, a sustained release profile in blood circulation was achieved compared with free drug solution by the evaluation of pharmacokinetic parameters. As a conclusion, the study reveals that Technetium-99m (99mTc radiolabeled) TRZ loaded SLN formulations could be promising theranostic agents based on their characterization profiles, in vitro cellular uptake and apoptosis induction capacity, and in vivo pharmacokinetic profiles.

Pre-clinic study of radiopharmaceutical for Covid-19 inactivation: Dose distribution with Monte Carlo Simulation.

Monte Carlo simulation method and Nuclear Medicine MIRD method were used to evaluate the effect of radiopharmaceuticals on Covid-19 disease. The mean absorbed organ dose in the target organ and gamma radiation emitter attenuation properties such as linear attenuation coefficients, energy absorption build-up factors (EABF), exposure build-up factors (EBF), and relative dose distributions (RDD) were examined. The results showed that radiopharmaceuticals containing gamma radiation emitters which are densely ionizing charged particles induced membrane damage and produced protein damage.

An Innovative Formulation Based on Nanostructured Lipid Carriers for Imatinib Delivery: Pre-Formulation, Cellular Uptake and Cytotoxicity Studies.

Imatinib (IMT) is a tyrosine kinase enzyme inhibitor and extensively used for the treatment of gastrointestinal stromal tumors (GISTs). A nanostructured lipid carrier system (NLCS) containing IMT was developed by using emulsification-sonication methods. The characterization of the developed formulation was performed in terms of its particle size, polydispersity index (PDI), zeta potential, entrapment efficiency, loading capacity, sterility, syringeability, stability, in vitro release kinetics with mathematical models, cellular uptake studies with flow cytometry, fluorescence microscopy and cytotoxicity for CRL-1739 cells. The particle size, PDI, loading capacity and zeta potential of selected NLCS (F16-IMT) were found to be 96.63 ± 1.87 nm, 0.27 ± 0.15, 96.49 ± 1.46% and -32.7 ± 2.48 mV, respectively. F16-IMT was found to be stable, thermodynamic, sterile and syringeable through an 18 gauze needle. The formulation revealed a Korsmeyer-Peppas drug release model of 53% at 8 h, above 90% of cell viability, 23.61 µM of IC50 and induction of apoptosis in CRL-1739 cell lines. In the future, F16-IMT can be employed to treat GISTs. A small amount of IMT loaded into the NLCSs will be better than IMT alone for therapy for GISTs. Consequently, F16-IMT could prove to be useful for effective GIST treatment.

The effect of radiolabeled nanostructured lipid carrier systems containing imatinib mesylate on NIH-3T3 and CRL-1739 cells.

The aim of current study is to develop new nanostructured lipid carrier systems (NLCSs) containing imatinib mesylate (IMT) and evaluate their targeting efficiency on NIH-3T3 as fibroblast cells and CRL-1739 as gastric adenocarcinoma cells with radiolabeled formulations. Three formulations (F1-IMT, F2-IMT and F3-IMT) were prepared and radiolabeled with 1 mCi/0.1 mL of [99mTc]Tc. The effect of reducing and antioxidant agents on radiolabeling process was evaluated and radiochemical purity of formulations was performed by radio thin-layer radiochromatography (RTLC). The results demonstrated that the radiochemical purity was found to be above 90% for [99mTc]Tc-F1-IMT and [99mTc]Tc-F2-IMT, while radiochemical purity of [99mTc]Tc-F3-IMT was found to be 85.61 ± 2.24%. Also, [99mTc]Tc-F1-IMT and [99mTc]Tc-F2-IMT have better stability in cell medium and saline than [99mTc]Tc-F3-IMT. Targeting efficiency of [99mTc]Tc-F1-IMT and [99mTc]Tc-F2-IMT comparatively evaluated by cell binding studies with [99mTc]NaTcO4 on NIH-3T3 and CRL-1739 cells. The cell binding capacity and targeting/non-targeting cell uptake ratio of these two formulations was found to be higher than [99mTc]NaTcO4 in CRL-1739. It is thought that the knowledge achieved in this study would contribute to using [99mTc]Tc-F1-IMT and [99mTc]Tc F2-IMT as an diagnosis and treatment agents.

Applying Quality by Design Principles in the Development and Preparation of a New Radiopharmaceutical: Technetium-99m-Imatinib Mesylate.

The clinical impact and accessibility of 99mTc tracers for cancer diagnosis would be greatly enhanced by the availability of a new, simple, and easy labeling process and radiopharmaceuticals. In this study, Technetium-99m-imatinib mesylate ([99mTc]TcIMT) was developed and prepared as a new radiopharmaceutical for breast cancer diagnosis. The effect of critical process parameters on the product quality and stability of [99mTc]TcIMT was investigated using the quality by design concept of the ICH Q8 (Pharmaceutical Development) guideline. [99mTc]TcIMT was subjected to in vitro cell binding studies to determine healthy and cancer cell affinity using HaCaT and MCF-7 cells, respectively. The optimal radiolabeling procedure with 1 mg of IMT, 500 µg of stannous chloride, 0.1 mg of ascorbic acid, and 1mCi 99mTc radioactivity was obtained for [99mTc]TcIMT. The pH of the reaction mixture was adjusted to 10 and allowed to react for 15 min at room temperature. The radiochemical purity of [99mTc]TcIMT was found to be higher than 90% at room temperature up to 6 h. Chromatography analysis revealed >85% [99mTc]TcIMT complex formation with promising stability in saline, cell medium, and serum up to 6 h. The radiolabeled complex showed a higher cell-binding ratio to MCF-7 cells (88.90% ± 3.12) than HaCaT cells (45.64 ± 4.72) when compared to 99mTc. Our findings show that the developed preparation method for [99mTc]TcIMT falls well within the proven acceptable ranges. Applying quality by design (QbD) principles is feasible and worthwhile for the preparation of [99mTc]TcIMT. In conclusion, radiochemical purity, stability, and in vitro cell binding evaluation of the [99mTc]TcIMT complex indicate that the agent can be utilized for imaging of breast cancer cells.

Development and Evaluation of Liquid and Solid Lipid Based Drug Delivery Systems Containing Technetium-99m-Radiolabeled Alendronate Sodium.

OBJECTIVE: The purpose of this study was to develop lipid-water based drug delivery system of Alendronate Sodium (ALD) in liquid and solid form obtained by using spray drying method and compare these two forms with radioactive cell culture studies. METHODS: This study included the development of liquid and solid form obtained by spray drying method, radiolabelling of ALD with 99mTc, preparation of formulations containing 99mTc -ALD and evaluation of their permeability with Caco-2 cell. The liquid formulations have been developed by using various surfactants, co-surfactants, oil and water phases. Physicochemical characterizations like droplet size, polydispersity index (PDI) and zeta potential measurements and short term stability studies were investigated. RESULTS: According to the measurement results, two oil in water formulations (F1-L and F2-L) were selected and spray dried with Buchi mini spray dryer apparatus to provide solid formulations (F1-S and F2-S). ALD was labeled with 99mTc and added to formulations. The effect of experimental conditions on radiolabeling efficiency of ALD and stability of all formulations containing 99mTc-ALD were investigated through Radio Thin Layer Chromatography (RTLC). It was observed that the labeling efficiency of ALD was greater than 90% and all formulations were found to be stable up to 6 h at room temperature. Permeability of radiolabeled ALD from all formulations was performed by using Caco-2 cells. According to the cell culture studies, permeability from spray dried formulations of ALD was found higher than liquid formulations. CONCLUSION: As a conclusion, spray dried formulations could be a promising drug delivery system for enhancing the permeability of ALD. Furthermore, this study is a good example of the use of radiolabeled compounds in drug development.

Comparative permeability studies with radioactive and nonradioactive risedronate sodium from self-microemulsifying drug delivery system and solution.

The purpose of this work is to prepare a self-microemulsifying drug delivery system (SMEDDS) for risedronate sodium (RSD) and to compare the permeability with RSD solution. The solubility of RSD was determined in different vehicles. Phase diagrams were constructed to determine the optimum concentration of oil, surfactant, and cosurfactant. RSD SMEDDS was prepared by using a mixture of soybean oil, cremophor EL, span 80, and transcutol (2.02:7.72:23.27:61.74, w/w, respectively). The prepared RSD SMEDDS was characterized by droplet size value. In vitro Caco-2 cell permeability studies were performed for SMEDDS and solution of radioactive ((99 m)Tc-labeled RSD) and nonradioactive RSD. The experimental results indicated that RSD SMEDDS has good stability and its droplet size is between 216.68 ± 3.79 and 225.26 ± 7.65 during stability time. In addition, RSD SMEDDS has higher permeability value than the RSD solution for both radioactive and nonradioactive experiments. The results illustrated the potential use of SMEDDS for delivery of poorly absorbed RSD.