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Biological affinity evaluation of Lawsonia inermis origin Lawsone compound and its radioiodinated form via in vitro methods
(Springer, 2015) Tekin, Volkan; Muftuler, F. Zumrut Biber; Guldu, Ozge Kozgus; Kilcar, Ayfer Yurt; Medine, E. Ilker; Yavuz, Murat; Unak, Perihan; Timur, Suna
WST-1-based cytotoxicity assay of lawsone (LW) was performed on MCF7, Caco2, BJ and Keratinocyte cells and viabilities were found as over 90 % for all cells. Significant wound healing effect of LW was reported on Keratinocyte cells. Antibacterial and antifungal activities of LW were tested on seven microorganisms with three concentrations and 1,000 A mu g/disc of LW showed antibacterial effect on Bacillus subtilis. In vitro cell incorporation of radioiodinated LW (I-131-LW) was evaluated on same cells. Keratinocyte cells uptake were 5 times more. Consequently, I-131-LW was found usable for researches about especially skin diseases in addition to breast and intestinal cancer.
Examination of the Association Between 3,4-Divanillyltetrahydrofuran Lignan (Urtica dioica Origin) and Prostate Cancer Cells by I-131 Radiolabeling
(Mary Ann Liebert, Inc, 2020) Tekin, Volkan; Guldu, Ozge Kozgus; Medine, Emin Ilker; Muftuler, Fazilet Zumrut Biber
Background: Prostate cancer is the most common type of cancer for men in many countries. One of the various prostate cancer therapy methods is hormone therapy, and explaining the association between androgen hormones and prostate cancer is a critical role for successful prostate cancer treatment. Materials and Methods: in the current study, the behavior of 3,4- divanillyltetrahydrofuran (DTH) was examined against prostate cancer cells, which have androgen sensitivity differences [LNCaP (+), PC3 (-)]. For this aim, DTH was obtained by extraction of Urtica dioica roots. the molecular structure of isolated compound was confirmed as DTH by liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy analyses. To evaluate the association of androgen sensitivity, DTH was radiolabeled with I-131, and cell uptake assay was performed by using I-131-radiolabeled DTH. Also, cytotoxicity (WST-1) assay of DTH was performed against LNCaP and PC3 cells to determinate the toxic effects of DTH on different androgen mechanisms. Results: the results of assays on cells have shown that DTH lignan behaves different like being more toxic to LNCaP cells than PC3 cells, depending on androgen sensitivity. Conclusion: the results may contribute both the research topics of phytolignan prostate cancer and androgen-sensitive prostate cancer.
Green synthesis of silver nanoparticles by using eugenol and evaluation of antimicrobial potential
(Wiley, 2019) Tekin, Volkan; Guldu, Ozge Kozgus; Dervis, Emine; Kilcar, Ayfer Yurt; Uygur, Emre; Muftuler, F. Zumrut Biber
The importance of green synthesis was revealed with advantages such as: eliminating the use of expensive chemicals; consume less energy; and generate environmentally benign products. With this aim, silver nanoparticles (AgNPs) were synthesized by using isolated eugenol from clove extract. Its antimicrobial potential was determined on three different microorganisms. Clove was extracted and eugenol was isolated from this extract. Green synthesis was performed and an anti-microbial study was performed. All extraction and isolation analyses were performed by high-performance liquid chromatography (HPLC); identification and confirmation were achieved using liquid chromatography-mass spectrometry (LC-MS); and scanning electron microscopy was used for characterization. Both HPLC and LC-MS analyses showed that eugenol obtained purely synthesized AgNPs and 20-25-nm-sized and homogeneous shaped particles seen in images. The antimicrobial effects of AgNPs at eight concentrations were determinated against Staphylococcus aureus, Escherichia coli and Candida albicans, and maximum inhibition zone diameters were found as 2.6 cm, 2.4 cm and 1.5 cm, respectively. The results of the antimicrobial study showed that eugenol as a biological material brought higher antimicrobial effect to AgNPs in comparison to the other materials found in the literature.
Hyaluronic acid-modified [F-19]FDG-conjugated magnetite nanoparticles: in vitro bioaffinities and HPLC analyses in organs
(Springer, 2018) Yasakci, Volkan; Tekin, Volkan; Guldu, Ozge Kozgus; Evren, Vedat; Unak, Perihan
In this study, we designed and synthesized [F-19]FDG-(2-deoxy-2-[fluorine-19]fluoro-d-glucose) conjugated iron oxide magnetic nanoparticles ([F-19]FDG-MNPs) for hybrid imaging and hyperthermia treatment. MNPs were synthesized, silica coated, and fabricated with TEOS (tetraethyl orthosilicate). They were then covered with hyaluronic acid (HA) to enhance their bioavailability. The modified MNPs were conjugated with [F-19]FDG and optically labeled with ICG (indocyanine green). The in vitro bioaffinities were surveyed in MCF7 and PC3 cell lines. In vivo bioaffinies were determined using Sprague-Dawley rats.
In Vitro Determination of Wound. Healing Potential of Axonge
(H M P Communications, 2017) Bilgi, Ahmet; Muftuler, Fazilet Zumrut Biber; Akman, Levent; Medine, Emin Ilker; Bilgi, Pinar Tonbaklar; Guldu, Ozge Kozgus; Gokulu, Sevki Goksun; Tekin, Volkan; Terek, Mustafa Cosan
Background. Research on treatment alternatives that improve wound healing is an ever-evolving area in medicine, and a wound healing agent that carries minimal pain, discomfort, and scarring for patients with burn wounds, venous and decubitis ulcers, traumatic wounds, and many others is needed. The phases of wound healing include homeostasis, inflammation, migration, proliferation, and maturation. Adeps suillus (axonge) is known as a therapeutic agent for skin diseases and mainly consists of triglycerides. Objective. In the current study, the proliferation effect of axonge was determined on human normal epidermal keratinocyte (HaCaT) cells and human normal foreskin fibroblast cell line (BJ) cells. Materials and Methods. Experimental steps included preparation of HaCaT and BJ cell lines, axonge's stable tetrazolium salt-based proliferation assay, and evaluation of the wound healing effect of axonge on HaCaT and BJ cells. Results. Axonge concentrations of 3.12 mu g/mL, 6.25 mu g/mL, 12.5 mu g/mL, 25 mu g/mL, and 50 mu g/mL showed no cytotoxic effect on both HaCaT and BJ cells for 24, 48, and 72 hours. Considering the wound area of HaCaT cells, after 6 hours the wound healing effect of the axonge group reached almost 70% and then stopped. According to the results of the study on. BJ cells, after 6 hours axonge wound closure was found to be 50% while the control group was only 10%. Conclusion. On the basis of this study, the authors determined that axonge might have potential for use in wound healing.
An in-vivo pilot study into the effects of FDG-mNP in cancer in mice
(Public Library Science, 2018) Aras, Omer; Pearce, Gillian; Watkins, Adam J.; Nurili, Fuad; Medine, Emin Ilker; Guldu, Ozge Kozgus; Tekin, Volkan; Wong, Julian; Ma, Xianghong; Ting, Richard; Unak, Perihan; Akin, Oguz
Purpose Previously, fluorodeoxy glucose conjugated magnetite nanoparticles (FDG-mNPs) injected into cancer cells in conjunction with the application of magnetic hyperthermia have shown promise in new FDG-mNPs applications. The aim of this study was to determine potential toxic or unwanted effects involving both tumour cells and normal tissue in other organs when FDG-mNPs are administered intravenously or intratumourally in mice. Materials and methods FDG-mNPs were synthesized. A group of six prostate-tumour bearing mice were injected with 23.42 mg/ml FDG-mNPs (intravenous injection, n = 3; intratumoural injection into the prostate tumour, n = 3). Mice were euthanized and histological sampling of tissue was conducted for the prostate tumour, as well as for lungs, lymph nodes, liver, kidneys, spleen, and brain, at 1 hour (n = 2) and 7 days (n = 4) post-injection. A second group of two normal (non-cancerous) mice received the same injection intravenously into the tail vein and were euthanised at 3 and 6 months post-injection, respectively, to investigate if FDG-mNPs remained in organs at those time points. Results In prostate-tumour bearing mice, FDG-mNPs concentrated in the prostate tumour, while relatively small amounts were found in the organs of other tissues, particularly the spleen and the liver; FDG-mNP concentrations decreased over time in all tissues. In normal mice, no detrimental effects were found in either mouse at 3 or 6 months. Conclusion Intravenous or intratumoural FDG-mNPs can be safely administered for effective cancer cell destruction. Further research on the clinical utility of FDG-mNPs will be conducted by applying hyperthermia in conjunction with FDG-mNPs in mice.
Isolation and Immobilization of His-Tagged Alcohol Dehydrogenase on Magnetic Nanoparticles in One Step: Application as Biosensor Platform
(Taylor & Francis Inc, 2014) Guldu, Ozge Kozgus; Ece, Selin; Evran, Serap; Medine, E. Ilker; Demirkol, Dilek Odaci; Unak, Perihan; Timur, Suna
His-tagged Alcohol dehydrogenase was produced as a recombinant protein in E. coli. Afterwards, isolation and immobilization of the enzyme was carried in one-step via copper modified magnetic nanoparticles (MNPs) by the effect of interactions between Cu and histidine. The resulting enzyme bound MNPs was then attached to the surface of carbon paste electrode by the magnetic force and used as an electrochemical biosensor for the alcohol sensing applications.
Isolation of resveratrol from peanut sprouts, radioiodination and investigation of its bioactivity on neuroblastoma cell lines
(Springer, 2020) Karatay, Kadriye Busra; Kilcar, AyferYurt; Guldu, Ozge Kozgus; Medine, Emin Ilker; Muftuler, Fazilet Zumrut Biber
Recently, natural antioxidant substances have been purified in a significant increasing incline from different plants for diagnosis and treatment options. in the current study, Resveratrol (RES) was isolated and radioiodinated with iodine-131 ([I-131]iodo-RES). Cell culture studies were conducted on neuroblastoma cells (SY-SH5Y and SK-N-AS) to investigate the bioavailability of [I-131]iodo-RES. the radioiodination yield of RES was 98.81 +/- 0.37% (n = 6). Uptake values up to 25% were observed notably on SK-N-AS cells until 24 h. Briefly; the current study will contribute to the development of novel radiolabeled plant origin agents for the imaging of neuroblastoma cells.
Multifunctional molecular imaging probes for estrogen receptors: Tc-99m labeled diethylstilbestrol (DES) conjugated, cuinp quantum dot nanoparticles (DESCIP)
(Springer, 2017) Moharrami, Payam; Unak, Perihan; Guldu, Ozge Kozgus; Medine, E. I.; Gumuser, Gul; Bilgin, Elvan Sayit; Aras, Omer
A theranostic nanoparticle was synthesized based on diethylstilbestrol conjugated with phosphate, copper, and indium (DESCIP) and labelled with Tc-99m which can be used for SPECT imaging of ER-enriched cancers. In vitro biological activity of Tc-99m-DESCIP was examined in breast adenocarcinoma cells (MCF-7), prostatic carcinoma cells (PC-3), and pulmonary epithelial cells (A-549). In vivo lymph node imaging was performed in normal and receptor blocked female New Zealand rabbits. Results demonstrated that Tc-99m-DESCIP and DESCIP has potential for imaging ER-enriched tumors such as breast and prostate tumors, and their metastases in the lung, as well as improving management for their therapies.
Nanoencapsulation of green tea catechin (-)-Epigallocatechin-3-Gallate (EGCG) in niosomes and assessment of its anticancer activity against lung cancer
(Elsevier, 2024) Evren, Damla Karaman; Guldu, Ozge Kozgus; Tut, Ezgi; Medine, Emin Ilker
Lung cancer is one of the leading causes of cancer-related deaths worldwide. In chemotherapy, the use of strong cytotoxic drugs and the specificity problems of these drugs also affect healthy cells and tissues. For this reason, the purpose of cancer treatment is to ensure that a suitable drug directly affects cancer cells at the appropriate dose. With nanotechnology, steps have been taken for an effective treatment that develops nano-transporters to deliver the drug molecule to the target cell in a specific, controlled manner. Another development is the discovery of theranostic agents used for both diagnostic and therapeutic purposes. In this study, a smart molecule was developed using the anticancer and antioxidant Epigallocatechin-3-Gallate (EGCG) molecule found in green tea, which is commonly consumed in our society. This molecule was encapsulated with niosomes to increase its stability and specificity. In this study, niosomes with an average size of 150 nm were synthesized using the thin film hydration technique. The zeta potential value of niosomes varied between -25 mV and -30 mV. Niosomes have been functionalized with indocyanine green (ICG) fluorescent dye and made suitable for optical imaging. The encapsulation efficiencies of the EGCG molecule and the ICG fluorescent dye were 10.1 % and 34.4 %, respectively. The release of EGCG from niosomes was an initial fast and then a slower release. 32 % of EGCG was released from niosomes within the first 3 h. Also, Cetuximab molecule was conjugated to niosomes with 75.8 % efficiency in order to provide lung cancer specificity and increase the anticancer effect. DLS, FTIR, XPS and TEM were used in the characterization phase of nanoparticles. While DLS and TEM provide information about dimensional analysis, FTIR and XPS were performed to verify the conjugations. Cytotoxicity, apoptosis, fluorescence imaging and incorporation studies of the molecule design created for theranostic purposes in A549 lung carcinoma and BEAS-2B normal bronchial epithelial cells were examined in vitro. As a result of these studies, it was determined that the synthesized molecule design has more involvement, toxic and apoptotic effects on A549 lung carcinoma cells. In this study, the therapeutic efficacy of the synthesized niosomal molecule design on the target cell and its potential to be used in cancer treatment were revealed and it is thought that it will contribute to the field of biotechnology.
A novel anti-angiogenic radio/photo sensitizer for prostate cancer imaging and therapy: Zr-89-Pt@TiO2-SPHINX, synthesis and in vitro evaluation
(Elsevier Science Inc, 2021) Tekin, Volkan; Aweda, Tolulope; Guldu, Ozge Kozgus; Muftuler, F. Zumrut Biber; Bartels, Jennifer; Lapi, Suzanne E.; Unak, Perihan
Prostate cancer is the most common malignancy and leading cause of cancer deaths in men. Thus, the development of novel strategies for performing combined prostate cancer imaging and therapy methods is crucial and could have a significant impact on patient care. This current study aimed to design a multimodality nanoconjugate to be used for both PET and optical imaging and as a therapeutic radio/photo sensitizer and anti-angiogenesis agent. Initial characterization of this novel nanoconjugate was performed via HPLC, FTIR, TEM and DLS analyses. Pt@TiO2-SPHINX was further evaluated using fluorometric and radiochromatographicmethods. Cytotoxicity, cell uptake and internalizationwere also investigated as well as therapy with photodynamic/radio therapy combinations. Both nanoparticles and nanoconjugates were robustly synthesized according to literature methods. Radiochemistry and cell culture assays showed high Zr-89 radiolabeling efficiency with sufficient stability for studies at later time points. Pt@TiO2-SPHINX was shown to target prostate cancer cells (PC3 and LNCaP), and was non-toxic to normal prostate cells (RWPE-1). This finding was supported by the WST-8 assay and AFM images. The uptake of the compound in prostate cancer cells is significantly higher than prostate normal cells and according to ELISA results, Pt@TiO2-SPHINX can increase anti-angiogenic VEGFA(165b). Additionally, Pt@TiO2-SPHINX dramatically decreased the cell viability of prostate cancer cells when photodynamic and radio therapy were performed at the same time. in vitro results are promising for future studies of Pt@TiO2-SPHINX as a PET imaging agent and anti-angiogenic radio sensitizer. (C) 2021 Elsevier Inc. All rights reserved.
A novel theranostic nanobioconjugate: I-125/131 labeled phenylalanine conjugated boron nitride nanotubes
(Springer, 2017) Guldu, Ozge Kozgus; Unak, Perihan; Timur, Suna
Here we report the synthesis of boron nitride nanotubes (BNNTs) via a chemical vapor deposition method, as potential agents for boron neutron capture therapy. BNNTs were functionalized with PAMAM[G-2] dendrimer and then, conjugated with L-Phe using EDC/NHS. After that, BNNTs were radiolabeled with I-125/131, which are commonly used for both therapy and diagnosis in clinical and pre-clinical studies. BNNTs were radiolabeled with a maximum yield with I-125/131 in compared with 4-borono-L-phenyalanine which is currently used as a commercial drug. Radiolabeling parameters were optimized with thin layer radiochromatography and high performance liquid radiochromatography. BNNTs are promising nanobioconjugates as new theranostic agents.
Optical detection based spot test on electrospun nanofibers for glioblastoma cells
(Elsevier, 2024) Us, Aybuke Elif; Kirbay, Fatma Ozturk; Guldu, Ozge Kozgus; Odaci, Dilek
Paper-based diagnosis is enabled to be used in many applications in global health due to its low cost and simplicity of operation. Electrospun nanofibers (ESNFs) are useful platforms to prepare paper-based diagnostics. Herein, bead-free ESNFs were formed by electrospinning using polystyrene (PS) and poly (ethylene glycol) (PEG) polymers as a paper-based substrate. PS:PEG ESNFs were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), identification of swelling behavior, and Brunauer-Emmett-Teller (BET) analysis. Synthesized gold nanoparticles (AuNPs) were used as a colorimetric probe and GMT8 aptamer was conjugated on the surface of AuNPs. AuNP and AuNP-GMT8 were characterized by dynamic light scattering (DLS), UV-Visible spectrometry, and X-Ray photoelectron spectroscopy (XPS). The interaction of AuNP-GMT8 bioconjugates with glioblastoma cells was examined. The colored spots for the mixture of glioblastoma (U87MG) cells and AuNP-GMT8 were optically monitored both in the microplate wells and on the PS:PEG ESNFs. The linear range of colorimetric analysis on PS:PEG ESNFs was determined to be between 101-106 U87-MG cells/mL by smartphone using RGB color analysis.
A Pilot Study Into the Use of FDG-mNP as an Alternative Approach in Neuroblastoma Cell Hyperthermia
(Ieee-Inst Electrical Electronics Engineers Inc, 2016) Subramanian, Mahendran; Pearce, Gillian; Guldu, Ozge Kozgus; Tekin, Volkan; Miaskowski, Arkadiusz; Aras, Omer; Unak, Perihan
Herein, we present a pilot study concerning the use of fluorodeoxy glucose conjugated magnetite nanoparticles (FDG-mNP) as a potential agent in magnetic nanoparticle mediated neuroblastoma cancer cell hyperthermia. This approach makes use of the 'Warburg effect', utilizing the fact that cancer cells have a higher metabolic rate than normal cells. FDG-mNP were synthesized, then applied to the SH-SY5Y neuroblastoma cancer cell line and exposed to an ac magnetic field. 3D Calorimetry was performed on the FDG-mNP compound. Simulations were performed using SEMCAD X software using Thelonious, (an anatomically correct male child model) in order to understand more about the end requirements with respect to cancer cell destruction. We investigated FDG-mNP mediated neuroblastoma cytotoxicity in conjunction with ac magnetic field exposure. Results are presented for 3D FDG-mNP SAR mnp (10.86 +/- 0.99 W/g of particles) using a therapeutic dose of 0.83 mg/mL. Human model simulations suggest that 43 W/kg SAR Theo would be required to obtain 42 degrees C within the centre of a liver tumor (Tumor size, bounding box x = 64, y = 61, z = 65 [mm]), and that the temperature distribution is inhomogeneous within the tumor. Our study suggests that this approach could potentially be used to increase the temperature within cells that would result in cancer cell death due to hyperthermia. Further development of this research will also involve using whole tumors removed from living organisms in conjunction with magnetic resonance imaging and positron emission tomography.
PLGA encapsulation and radioiodination of indole-3-carbinol: investigation of anticancerogenic effects against MCF7, Caco2 and PC3 cells by in vitro assays
(Springer, 2017) Yildiz, Gorkem; Kilcar, Ayfer Yurt; Medine, E. Ilker; Tekin, Volkan; Guldu, Ozge Kozgus; Muftuler, F. Zumrut Biber
Encapsulation with PLGA of I3C and radioiodination have been performed. Anticancerogenic effects of I3C and I3C-PLGA have been investigated utilizing in vitro methods on breast adenocarcinoma epithelial (MCF7), colon adenocarcinoma epithelial (Caco2), prostate carcinoma epithelial (PC3) cells. Characterization of I3C-PLGA have been performed with DLS method and SEM analysis. I3C and I3C-PLGA compounds have been radiolabeled in high yields with I-131 which is widely used for diagnosis and treatment in Nuclear Medicine. All experimental results demonstrated that radioiodinated compounds are promising in order to be used in Nuclear Medicine as well as present study contributed previously reported studies.
Preparation and in vitro investigation of prostate-specific membrane antigen targeted lycopene loaded niosomes on prostate cancer cells
(Elsevier, 2023) Kusdemir, Bekir Cem; Guldu, Ozge Kozgus; Kilcar, Ayfer Yurt; Medine, Emin Ilker
In this study, it's aimed to develop prostate-specific membrane antigen (PSMA) targeted niosomes with a multifunctional theranostic approach.With this aim, PSMA-targeted niosomes were synthesized by a thin-film hydration method followed by bath sonication. Drug-loaded niosomes (Lyc-ICG-Nio) were coated with DSPE-PEG-COOH (Lyc-ICG-Nio-PEG) and subsequently anti-PSMA antibody conjugated to niosomes (Lyc-ICG-Nio-PSMA) with amide bond formation.Dynamic light scattering (DLS) analysis showed that the hydrodynamic diameter of Lyc-ICG-Nio-PSMA was approximately 285 nm and it was found with transmission electron microscopy (TEM) that the niosome formulation was spherical. Encapsulation efficiency was 45% and %65 upon dual encapsulation of ICG and lycopene. The results of fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) demonstrated that PEG coating and antibody coupling were successfully done.In vitro studies showed that cell viability decreased when lycopene was entrapped into niosomes applied while the total apoptotic cell population rose slightly. When Lyc-ICG-Nio-PSMA was applied to cells, decreased cell viability and enhanced apoptotic effect were seen compared to those for Lyc-ICG-Nio.In conclusion, it was demonstrated that targeted niosomes displayed improved cellular association and decreased cell viability on PSMA + cells.
Radioiodination of cyclin dependent kinase inhibitor Olomoucine loaded Fe@ Au nanoparticle and evaluation of the therapeutic efficacy on cancerous cells
(Walter De Gruyter Gmbh, 2017) Takan, Gokhan; Guldu, Ozge Kozgus; Medine, Emin Ilker
Magnetic nanoparticles have promising biomedical applications such as drug delivery, novel therapeutics and diagnostic imaging. Magnetic drug delivery combination works on the delivery of magnetic nanoparticles loaded with drug to the target tissue by means of an external magnetic field. Gold coated iron oxide (Fe@ Au) nanoparticles can provide useful surface chemistry and biological reactivity. Covalent conjugation to the Fe@ Au nanoparticles through cleavable linkages can be used to deliver drugs to tumor cells, then the drug can be released by an external. In this paper, purine based cyclin dependent kinases (CDKs) inhibitor Olomoucine (Olo) [2-(Hydroxyethylamino)-6-benzylamino-9-methylpurine] was loaded on gold coated iron oxide (Fe@ Au) nanoparticles and radiolabeled with I-131 to combine magnetic targeted drug delivery and radiotherapy. Fe@ Au nanoparticles were synthesized by microemulsion method. The characterization of nanoparticles was examined by TEM, VSM and XRD. Amine activation was utilized by cysteamine hydrochloride and then CDI was used for conjugation of Olomoucine. Antiproliferative effect and cytotoxicity of Olomoucine loaded Fe@ Au nanoparticles (Fe@ Au-Olo) were investigated on MCF7 and A549 cell lines. Proliferation rate was decreased while uptake of Fe@ Au-Olo on both cell lines was high in comparison with Olomoucine. Also, enhanced incorporation ratio was observed under external magnetic field.
Radioiodination of Pimonidazole as a Novel Theranostic Hypoxia Probe
(Bentham Science Publ Ltd, 2021) Inci, Ilknur Demir; Tekin, Volkan; Kilcar, Ayfer Yurt; Guldu, Ozge Kozgus; Medine, Emin Ilker; Karatay, Kadriye Busra; Dervis, Emine
Background: Tumors are defined as abnormal tissue masses, and one of the most important factors leading to the growth of these abnormal tissue masses is Vascular Endothelial Growth Factor, which stimulates angiogenesis by releasing cells under hypoxic conditions. Hypoxia has a vital role in cancer therapy, thus it is important to monitor hypoxia. The hypoxia marker Pimonidazole (PIM) is a candidate biomarker of cancer aggressiveness. Objective: The study aimed to perform radioiodination of PIM with Iodine-131 (I-131) to join a theranostic approach. For this purpose, PIM was derived as PIM-TOS to be able to be radioiodinated. Methods: PIM was derived via a tosylation reaction. Derivatization product (PIM-TOS) was radioiodinated by using iodogen method and was analyzed by High-Performance Liquid Chromatography and Liquid chromatography-mass spectrometry. Thin layer radiochromatography was utilized for its quality control studies. Results: PIM was derived successfully after the tosylation reaction. The radioiodination yield of PIM-TOS was over 85%. Conclusion: In the current study, radioiodination potential of PIM with I-13(1), as a potential theranostic hypoxia agent was investigated. Further experimental studies should be performed for developing a novel hypoxia probe including theranostics approaches.
Synthesis of Novel Plant-Derived Encapsulated Radiolabeled Compounds for the Diagnosis of Parkinson's Disease and the Evaluation of Biological Effects with In Vitro/In Vivo Methods
(Springer, 2024) Uygur, Emre; Karatay, Kadriye Busra; Dervis, Emine; Evren, Vedat; Kilcar, Ayfer Yurt; Guldu, Ozge Kozgus; Sezgin, Ceren
Parkinson's disease (PD) is a neurodegenerative disorder that affects millions of individuals globally. It is characterized by the loss of dopaminergic neurons in Substantia Nigra pars compacta (SNc) and striatum. Neuroimaging techniques such as single-photon emission computed tomography (SPECT), positron emission tomography (PET), and magnetic resonance imaging (MRI) help diagnosing PD. In this study, the focus was on developing technetium-99 m ([Tc-99m]Tc) radiolabeled drug delivery systems using plant-derived compounds for the diagnosis of PD. Madecassoside (MA), a plant-derived compound, was conjugated with Levodopa (L-DOPA) to form MA-L-DOPA, which was then encapsulated using Poly Lactic-co-Glycolic Acid (PLGA) to create MA-PLGA and MA-L-DOPA-PLGA nanocapsules. Extensive structural analysis was performed using various methods such as Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), liquid chromatography-mass spectrometry (LC-MS), thin layer chromatography (TLC), high performance liquid chromatography (HPLC), dynamic light scattering (DLS), and scanning electron microscopy (SEM) to characterize the synthesized products. Radiochemical yields of radiolabeled compounds were determined using thin layer radio chromatography (TLRC) and high performance liquid radio chromatography (HPLRC) methods. In vitro cell culture studies were conducted on human neuroblastoma (SH-SY5Y) and rat pheochromocytoma (PC-12) cell lines to assess the incorporation of [Tc-99m]Tc radiolabeled compounds ([Tc-99m]Tc-MA, [Tc-99m]Tc-MA-L-DOPA, [Tc-99m]Tc-MA-PLGA and [Tc-99m]Tc-MA-L-DOPA-PLGA) and the cytotoxicity of inactive compounds (MA and MA-L-DOPA compounds and encapsulated compounds (MA-PLGA and MA-L-DOPA-PLGA). Additionally, the biodistribution studies were carried out on healthy male Sprague-Dawley rats and a Parkinson's disease experimental model to evaluate the compounds' bioactivity using the radiolabeled compounds. The radiochemical yields of all radiolabeled compounds except [Tc-99m]Tc-L-DOPA-PLGA were above 95% and had stability over 6 h. The cytotoxic effects of all substances on SH-SY5Y and PC-12 cells increase with increasing concentration values. The uptake values of PLGA-encapsulated compounds are statistically significant in SH-SY5Y and PC-12 cells. The biodistribution studies showed that [Tc-99m]Tc-MA is predominantly retained in specific organs and brain regions, with notable uptake in the prostate, muscle, and midbrain. PLGA-encapsulation led to higher uptake in certain organs, suggesting its biodegradable nature may enhance tissue retention, and surface modifications might further optimize brain penetration. Overall, the results indicate that radiolabeled plant-derived encapsulated drug delivery systems with [99mTc]Tc hold potential as diagnostic agents for PD symptoms. This study contributes to the advancement of drug delivery agents in the field of brain research.
Thymoquinone Glucuronide Conjugated Magnetic Nanoparticle for Bimodal Imaging and Treatment of Cancer as a Novel Theranostic Platform
(Bentham Science Publ Ltd, 2021) Ince, Iskender; Muftuler, Zumrut Biber; Medine, E. Ilker; Guldu, Ozge Kozgus; Takan, Gokhan; Ergonul, Aysegul; Parlak, Yasemin
Background: Theranostic oncology combines therapy and diagnosis and is a new field of medicine that specifically targets the disease by using targeted molecules to destroy the cancerous cells without damaging the surrounding healthy tissues. Objective: We aimed to develop a tool that exploits enzymatic TQ release from glucuronide (G) for the imaging and treatment of lung cancer. We added magnetic nanoparticles (MNP) to enable magnetic hyperthermia and MRI, as well as 131I to enable SPECT imaging and radionuclide therapy. Methods: A glucuronide derivative of thymoquinone (TQG) was enzymatically synthesized and conjugated with the synthesized MNP and then radioiodinated with 131I. New Zealand white rabbits were used in SPECT and MRI studies, while tumor modeling studies were performed on 6-7-week-old nude mice utilized with bioluminescence imaging. Results: Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectra confirmed the expected structures of TQG. The dimensions of nanoparticles were below 10 nm and they had rather polyhedral shapes. Nanoparticles were radioiodinated with 131I with over 95% yield. In imaging studies, in xenograft models, tumor volume was significantly reduced in TQGMNP-treated mice but not in non-treated mice. Among mice treated intravenously with TQGMNP, xenograft tumor models disappeared after 10 and 15 days, respectively. Conclusion: Our findings suggest that TQGMNP in solid, semi-solid and liquid formulations can be developed using different radiolabeling nuclides for applications in multimodality imaging (SPECT and MRI). By altering the characteristics of radionuclides, TQGMNP may ultimately be used not only for diagnosis but also for the treatment of various cancers as an in vitro diagnostic kit for the diagnosis of beta glucuronidase-rich cancers.

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