Tungsten-ethylene vinyl acetate (EVA) composite as a gamma rays shielding material

Lead is a highly toxic metal, also heavy in personal shielding. This negative aspect decline us to search for alternative shielding material that is free of toxic effect, environment friendly, lighter and easy to use individually. Polymer, being lighter, may constitute an alternative to lead, but it has a much lower density and does not serve in gamma shielding by it. Therefore, high density tungsten could be added to polymer in order to shield gamma rays. In this study ethylene vinyl acetate (EVA) and tungsten were mixed in certain amounts and thus discs have been produced from this mixture. The results show that EVA-Tungsten composite is an effective shielding material for gamma shielding

Selective Photokilling of Human Pancreatic Cancer Cells Using Cetuximab-Targeted Mesoporous Silica Nanoparticles for Delivery of Zinc Phthalocyanine

Background: Photodynamic therapy (PDT) is a non-invasive and innovative cancer therapy based on the photodynamic effect. In this study, we sought to determine the singlet oxygen production, intracellular uptake, and in vitro photodynamic therapy potential of Cetixumab-targeted, zinc(II) 2,3,9,10,16,17,23,24-octa(tert-butylphenoxy))phthalocyaninato(2-)-N29,N30,N31,N32 (ZnPcOBP)- loaded mesoporous silica nanoparticles against pancreatic cancer cells. Results: The quantum yield (Φ∆) value of ZnPcOBP was found to be 0.60 in toluene. In vitro cellular studies were performed to determine the dark- and phototoxicity of samples with various concentrations of ZnPcOBP by using pancreatic cells (AsPC-1, PANC-1 and MIA PaCa-2) and 20, 30, and 40 J/cm2 light fluences. No dark toxicity was observed for any sample in any cell line. ZnPcOBP alone showed a modest photodynamic activity. However, when incorporated in silica nanoparticles, it showed a relatively high phototoxic effect, which was further enhanced by Cetuximab, a monoclonal antibody that targets the Epidermal Growth Factor Receptor (EGFR). The cell-line dependent photokilling observed correlates well with EGFR expression levels in these cells. Conclusions: Imidazole-capped Cetuximab-targeted mesoporous silica nanoparticles are excellent vehicles for the selective delivery of ZnPcOBP to pancreatic cancer cells expressing the EGFR receptor. The novel nanosystem appears to be a suitable agent for photodynamic therapy of pancreatic tumor

Uranyumun seyreltik sulu çözeltilerden, inorganik adsorbanlar üzerinde adsorpsiyonunun araştırılması

ÖZET Bu çalışmada seyrelttk sulu çöze 1 t İ I erdeki uranyumun aliminyum hidroksit, demir hidroksit ve taşıyıcıdan (si 1 ika j e 1 veya aktif karbon) oluşan adsorbaniarda adsorpsiyonu incelenmiştir. Adsorbanlar ağırlıkça I kısım aliminyum hidroksit, 3 kısım demir (III) hidroksit ve 4 kısım taşıyıcı içere cek şekilde hazırlanmışlardır. Seyreltik sulu çöze I t i 1 erdeki uranyumun, adsorban üzerinde tutulması değişik pH ve sıcaklıklarda yapıl mıştır. Denenen adsorbanl ardaki maksimum uranyum adsorp- siyonunun, taşıyıcısı silikajel olan adsorbanda pH: 4.5- 5.5 İle pH: 8.0 - 8.5 aralıklarında, taşıyıcısı aktif karbon olan adsorbanda ise pH: 4.5 ile pH: 7.0 - 8.5 dolaylarında olduğu saptanmıştır. Her iki adsorban için oda sıcaklığında çalışmanın uygun olacağı tesbit edil miştir. Optimum koşullarda, taşıyıcısı silikajel olan adsorbandaki adsorpsiyon verimi % 81, diğerinde İse % 89' dur. Değişik uranyum konsant rasyon 1 ar ı ndak i çözeltilerle çalışılarak, adsorbanl ar in adsorpsiyon kapasiteleri saptanmıştır. Sulu çözel t i I erdeki uranyumun adsorpsiyo- nun, Langmuir tipi adsorpsiyon izotermine uymaktadır. Elüsyon denemelerinde farklı çözeltiler kullanılmış olup, İN (NH.)" 00, ' in en uygun elüsyon çözeltisi olduğu tesbit edilmiştir. Taşıyıcı maddesi silikajel olan adsorbanda elüsyon verimi % 89.77, aktif karbonlu adsorban için bu değer % 62 'dirSUMMARY In this study, the adsorption of uranium ffom a dilute aqueous solution by inorganic adsorbents have been investigated. These adsorbents contain aliminium hydroxide, ferric hydroxide and support material in the Weight ratio I: 3:4. The separation of uranium from dilute aqueous solution by adsorbent under various pH values and temperature (°C) has been studied. It has been found that the adsorbabi I İ ty of uranium exhibits a maximum at pH: 4.5-5.5 and pH: 8.0-8.5 (support mater t a 1 -s i I ica gel) and at pH: 4.5 and pH: 7.0-8.5 (support material - activated carbon). It has been concluded that the ambient temperature is favorable on the adsorbtion process. In the optimum conditions, the adsorption efficiency of the adsorbents supported by silica gel and activated carbon, are 81 89 % respect i vely. The influence (or effect) of uranium concentration on the capacities of the mixed adsorbents were investiga- 2 + ted and determined. Adsorption of VOt ions in aqueous solution follows the Langmuir type iso therm. Different solutions have been tested in the elution process. It has been found that IN (NH.)- CO, is the most succesful eluting solution. The elution efficiency the adsorbent in which the support material is silica-gel has been found as 89.77 % and In which the support material is activated carbon as 62 %

Benzodiazepin (Diazepam) ve cyclopyrrolone (Zopiclone) grubu formasötiklerinin I-131 ile işaretlenmesi

Since usage of radioisotopically labeled radiopharmaceuticals increase day by day, importance of the other disciplines that is related with this area have increased. Certainly developing of the Nuclear Medicine dependes on the Radiopharmacy and Radiochemistry that are the most related disciplines with this scientific area. In this study, diazepam is a derivative of the 1.4 benzodiazepine family that the most widely used drugs as anticonvulsant agents and zopiclone (4-methyl-l-piperazine carboxylic acid, 6-(5-chloro~2- pyridyl)-6,7-dihydro-7-oxo-5 H- pyrrolo-[3.4-b]-pyrazin 5-yl ester) is a new derivative of the cyclopyrrolone family have been labeled with I- 131, as new radiopharmaceuticals and their radiopharmaceutical potentials have been determined. CAT and iodogen methods have been tried for labeling of diazepam with 1-131 and optimum labeling conditions have been determined for both methods. The optimum conditions for CATmethods; diazepam amount is 1 mg, CAT amount is 11.2 mg, reaction time is 30 minutes, reaction temperature is room temperature. 131IDZ yield is 72.5 % according to this method. The specific activity of labeled compound was 0.28 Ci/mmol level. The optimum conditions for iodogen method; diazepam amount is 1-5 mg, iodogen amount is 1 mg, reaction time is 15-20 minutes and reaction temperature is room temperature. Eighty-four percent and 64 % labeling yields were obtained for acidic and neutral media respectively. Specific activity of labeled compound was 0.28 Ci/mmol level. Labeling of zopiclone with 1-131 couldn't be succeeded by these methods. For this reason, halogen exchange at melting point method was tried and gave good result. Optimum labeling conditions according to this method; zopiclone amount is 1 mg, reaction temperature is 70-80 °C, reaction time is one hour. Labeling yield is 96.8 %. The specific activity of labeled compound was 0. 15 Ci/mmol level. The ratios of n-octanol/water were determined for both radiopharmaceuticals 1.9 for 131IDZ, 1.6 for 131IZP were found. In vivo experiments have been done to determine radiopharmaceutical potentials of both labeled compounds. Biodistribution studies on rats showed that 13 lTDZ has accumulated in kidneys, liver, lungs, brain tissues while 131IZP has accumulated in spleen, muscle, lungs, liver, fat tissus and brain tissues. Scintigraphic results taken with gamma camera on rabbits agree with biodistribution results of rats. Keywords: Diazepam, Zopiclone, iodogen method, labelled with 1-131, halogen exchange method, CAT method.Kısa ömürlü radyoizotoplarla işaretli radyofarmasötiklerin Nükleer Tıp'taki kullanımlarının günden güne artması bu radyoizotopların elde edilmesi ve radyofarmasötiklerin hazırlanması ile ilgili diğer disiplinlerin de önemini arttırmıştır. Kuşkusuz Nükleer Tıp'ın gelişmesi bu konu ile ilgili disiplinler olan Radyofarmasi ve Radyokimya'nın da gelişmesine bağlıdır. Bu çalışmada bu düşünceden hareketle yeni bir radyofarmasötikler grubu olarak benzodiazepin grubundan 1.4 benzodiazepin ailesinin bir üyesi olan ve geniş çapta uyku ilacı olarak kullanılan diazepam, cyclopyrrolone ailesinin yeni bir türevi olan zopiclone (4-metil -1- piperazin karboksilik asit, 6-(5-kloro-2-piridin)-6-7-dihidro 7-okso-5 H- pirrol [3.4-b] pirazin-5 ester) isimli farmasötikler I-131 ile işaretlenmiş ve radyofarmasötik potansiyelleri belirlenmeye çalışılmıştır. Diazepam'ın I-131 ile işaretlenmesi ile ilgili olarak CAT ve iodogen yöntemleri denenmiş ve her iki yöntem için de optimum işaretlenme koşulları belirlenmiştir. CAT yöntemi için en uygun koşullar;diazepam miktarı 1 mg, CAT miktarı 11.2 mg, reaksiyon süresi 30 dakika, reaksiyon sıcaklığı oda sıcaklığı'dır. Bu yönteme göre elde edilen 13 l IDZ verimi %72.5'dir. İodogen yöntemine göre ise uygun koşullar; diazepam miktarı 1-5 mg, iodogen miktarı 1 mg, reaksiyon süresi 15-20 dakika ve reaksiyon sıcaklığı oda sıcaklığı olarak belirlenmiştir. Asidik şartlarda yapılan işaretlemede % 84 işaretleme verimi elde edilirken ticari ampul çözeltisi içindeki nötral şartlarda % 64 işaretlenme verimi elde edilmiştir. Bu şartlarda elde edilen 131IDZ'in spesifik aktivitesi 0.28 Ci/mmol mertebesindedir. Zopiclone'nun 1-131 ile işaretlenmesinde bu yöntemler başarılı olmamış ve erime noktasında halojen yer değiştirme yöntemi iyi sonuç vermiştir. Bu yöntemde en uygun işaretleme koşullan; zopiclone miktarı 1 mg, reaksiyon sıcaklığı 70-80 °C, reaksiyon süresi 1 saat'dir. Bu koşullarda 131IZP verimi % 96.8 dir. Spesifik aktivite 0.15 Ci/mmol mertebesindedir. Her iki radyofarmasötiğin lipofilitesini tesbit için n-oktanol/su oranlan tayin edilmiş ve 131IDZ için 1.9, 131IZP için 1.6 bulunmuştur. Her iki işaretli bileşiğinde radyofarmasötik potansiyelleri belirlemek için in vivo denemeler yapılmıştır. Sıçanlar üzerinde yapılan biyolojik dağılım çalışmaları 131IDZ'ın böbrek, karaciğer, akciğer, beyin gibi organlarda 131IZP'nun ise dalak, kas, akciğer, karaciğer, yağ dokusu, beyin gibi organlarda en çok birikim gösterdiklerini göstermiştir. Gama kamera ile tavşanlar üzerinde yapılan sintigrafik çalışma sonuçlan da sıçanlar ile yapılan biyolojik dağılım çalışması sonuçlarını desteklemektedir

Radiotracer Techniques in the Investigation of Metabolism of Medicinal Plants

WOS: 000268493600018This work presents the importance of the use of radiotracers for metabolic studies of medicinal plants. Labeling with a radioisotope provides compounds of high specific activity. For this reason, the labeled compounds have much advantages for metabolic and pharmacokinetic studies. It also includes some study related to the use of the method

Tümör görüntüleme ajanı olarak teknesyum-99m işaretli bombesin benzeri peptid konjugasyonu; HYNIC-Litorin'in hazırlanması ve in vitro değerlendirilmesi

Birçok tümör tipinde peptid reseptörleri fazladır ve peptidlerin bu reseptörlere bağlanması hedef doku tarafından peptidin tutulumunu sağlar. Küçük hücreli akciğer kanseri, prostat, meme, mide, kolon ve pankreas kanseri gibi pek çok tümörün Bombesin/GRP reseptörlerini içerdikleri bilinmektedir. Tc-99m (Teknesyum 99m); kimyası ve görüntüleme karakteristiği (140.5 keV gama enerjisi, t1/2 = 6.01 saat) açısından görüntüleme için tercih edilen bir radyonükliddir. Bu projenin amacı, BN-benzeri peptid konjugatı: HYNIC-Q-Litorin’in farklı ko-ligandlar (EDDA ve trisin) kullanılarak 99mTc radyoizotopu ile işaretlenmesi, işaretleme koşullarının optimize edilmesi ve in vitro çalışmalar ile pankreas tümörüne karşı potansiyelinin belirlenmesidir. Yeni hazırlanan 99mTc-trisin-HYNIC-Q-Litorin ve 99mTc-EDDA-HYNIC-Q-Litorin’in radyoişaretleme koşulları; pH, ko-ligand miktarı, kalay klorür miktarı, sıcaklık ve reaksiyon süresi optimize edildi. 99mTc-trisin-HYNIC-Q-Litorin ve 99mTc-EDDA-HYNIC-Q-Litorin için radyokimyasal verimler %98.0 ± 1.7 ve %97.5 ± 2.5 olarak belirlendi. İn vitro çalışmalarda; kanser hücrelerinde 99mTc ile işaretli peptid konjugatının AR42J (sıçan pankreas tümörü), MIA-PaCa-2 (insan pankreas karsinoma) ve PanC 02.13 (insan pankreas adenokarsinoma) hücreleri ve kontrol hücre hatlarında [Hs 574.Sk (insan fibroblast) ve PSI 2 12s6 (fare fibroblast)] tutulum potansiyeli değerlendirildi. Radyoişaretli peptid konjugatının kanser hücrelerine bağlanma affinitesinin kontrol hücre grubuna göre daha yüksek ve spesifik olduğu saptanmıştır. Elde edilen sonuçlar pankreas tümörü gibi bombesin reseptör pozitif tümörlerin görüntülenmesinde kullanılacak yeni bir radyofarmasötik oluşturulmasına katkı sağlayacaktır.Various peptide receptors are over-expressed in particular tumor types and these receptors binding of peptides is supplied to uptake by target tissue. It is known that small cell lung cancers, prostate carcinomas, glioblastoma, gastric, pancreatic, colon and breast carcinomas have Bombesin/GRP receptors. 99mTc radionuclide is chosen because of its excellent chemical and imaging characteristics (140.5 keV gamma energy, t1/2 = 6.01h). The goal of this project; HYNIC-Q-Litorin was to label with 99mTc radioisotope using different co-ligands (EDDA and tricine), to optimize of its labeling conditions and evaluate of its potential to pancreatic tumor in in vitro studies. The radiolabeling conditions of newly-formed 99mTc-tricine-HYNIC-Q-Litorin and 99mTc-EDDA-HYNIC-Q-Litorin; pH, amount of co-ligand, amount of stannous chloride, temperature and reaction time were optimized. Radiochemical yields for 99mTc-tricine-HYNIC-Q-Litorin and 99mTc-EDDA-HYNIC-Q-Litorin were found as 98.0 ± 1.7 and 97.5 ± 2.5%, respectively. In in vitro studies, the binding potential of 99mTc labeled peptide-conjugate was evaluated in AR42J (rat pancreatic tumor), MIA-PaCa-2 (human pancreas carcinoma) and PanC 02.13 (human pancreas adenocarsinoma) cell lines and control cell lines [Hs 574.Sk and PSI 2 12s6]. The binding affinity of the radiolabeled peptide-conjugate to the cancer cells was found to be higher and specific than that control cells. The results might be contribute for a new radiopharmaceutical to be used in imaging of bombesin receptor positive tumors such as pancreatic tumor

Chemo-Photothermal Combination Therapy of HER-2 Overexpressing Breast Cancer Cells with Dual-Ordered Mesoporous Carbon@Silica Nanocomposite

In cancer treatment, the complexity of tumors seriously affects the therapeutic potential of the treatment. Treatments with combination therapy result in more potent effects than monotherapy or their theoretical combination in cancer treatment. Photothermal therapy (PTT) includes applying phototherapeutic agents that cause local hyperthermia responsible for the thermal ablation of tumor cells after applying near-infrared light and is often applied with other combination therapies. In this study, the chemo-PTT potential of synthesized drug-loaded and targeted GEM/TRA-MC@Si nanocomposite on Her2 positive breast cancer cell line (SK-BR-3) and human triple-negative breast cancer cell line (MDA-MB-231) was investigated using NIR application as in vitro. First, the cell viability (IC50) value of the GEM/TRA-MC@Si nanocomposite was determined as 25 mu g/mu L. Then, chemo-PTT was performed, and the viability of the cells was evaluated. In addition, the live/dead cell rate was established by staining with the Calcein-AM and EthD-1, and apoptosis tests were completed. When the surface temperature of Her2 positive SK-BR-3 cells exceeded 47 degrees C during PTT with an irradiation time of > 100 s, it caused cell death. In this study, it was demonstrated that in vitro PTT (1 W/cm(2), 180 s) was applied using GEM/TRA-MC@Si nanocomposite (25 mu g/mL) on her2 + SK-BR-3 cell line, which contributed to the reduction of cell viability. In addition, this study demonstrates that chemo-PTT with targeted GEM/TRA-MC@Si nanocomposite induced SK-BR-3 cell viability and can initiate cell death through the apoptosis pathway under optimized irradiation conditions. Herewith chemo-PTT combination therapy of targeted GEM-TRA/MC@Si nanocomposite was found to be effective on SK-BR-3 cells as in vitro.Ege University Scientific Research Projects (BAP) Coordinator ship [FDK-2020-21380]; Scientific and Technical Research Council of Turkey (TUBITAK) [2211-C, 2214-A, 1649B031802269, 1059B141801597]Financial support was provided by Ege University Scientific Research Projects (BAP) Coordinator ship (Project Number: FDK-2020-21380) and the Scientific and Technical Research Council of Turkey (TUBITAK) with 2211-C and 2214-A coded doctoral research support (grant number, respectively: 1649B031802269 and 1059B141801597)

Radiopharmaceuticals developed for Zr-89-Immuno-PET

The development of molecular imaging agents used for imaging of cancer tissue is of great importance for the early detection of cancer. Positron emission tomography (PET) radiopharmaceuticals consists of a positron-emitting radionuclide and a molecularstructure. Zr-89-labeled monoclonal antibodies (mAbs), peptides, nanoparticles, proteins, and other compounds are called Zr-89-Immuno-PET and are used in cancer tissue imaging. This review provides a general overview of the potential of molecules labeled with Zr-89 radionuclide, which is chosen due to its long half-life, in preclinical and clinical studies. In light of these studies, radiopharmaceuticals created using nanoparticles have greater potential than those using antibodies