Radioiodination of zearalenone and determination of Lactobacillus plantarum effect of on zearalenone organ distribution: In silico study and preclinical evaluation.

Purpose: Zearalenone (ZEN) which is one of the known fusarium species mycotoxin, produced primarily on many cereal crops. Consequently, the current study aims to estimate the possibility of labeling zearalenone and the pattern of accumulation of the produced labeled zearalenone [125I]-ZEN in different mice tissues, and the possible protective effect of Lactobacillus plantarum to reduce organ accumulation of Zearalenone. Materials and methods: the experiment was conducted on two groups of mice were used; the two groups received [125I] Zearalenone administered by tail vein injection, the first group receive nothing else while the second group received also L. plantarum (as a control agent) orally. The mice were kept under observation for 120 min to monitor zearalenone distribution. Results: by monitoring the zearalenone distribution the maximum concentration was found to be mainly primarily in the intestine (45.8 %) followed by the liver (27.15 %) while in the ovary (the most susceptible organ was (3.22 %) after120 min, in the first group of mice. The same pattern was observed in the second group with concentrations of (46.1 %), (30.19 %) and (0.09 %) in the intestine, liver respectively. Conclusion: These results indicated the lactic acid bacteria played a role in decreasing labeled zearalenone in the ovaries which is the target organ. [125I]-labeled ZEN is a promising novel tracer for organ imaging and that a significant role that L. plantarum could play in decreasing the zearalenone bioavailability of in mice organs.

Radioiodination and biological evaluation of nizatidine as a new highly selective radiotracer for peptic ulcer disorder detection.

Nizatidine has been labeled using [125 I] with chloramine-T as oxidizing agent. Factors such as the amount of oxidizing agent, amount of substrate, pH, reaction temperature, and reaction time have been systematically studied to optimize the iodination. Biodistribution studies indicate the suitability of radioiodinated nizatidine as a novel tracer to image stomach ulcer. Radioiodinated nizatidine may be considered a highly selective radiotracer for peptic ulcer imaging.

Radioiodination and biological evaluation of candesartan as a tracer for cardiovascular disorder detection.

The goal of the study aims to evaluate newly radioiodinated candesartan (CAN) as a potential cardiovascular tracer. CAN was labeled using 125 I with chloramine-T (Ch-T) and N-bromosuccinimide (NBS) with full characterization of cold Iodo-candesartan. Factors such as pH, reaction temperature, reaction time, substrate, and oxidizing agent amounts were studied to optimize the radioiodination of CAN. The optimum radiochemical yield of 125 I-CAN was 98%. The labeled compound was separated and purified using high-pressure liquid chromatography. The biological distribution indicates the suitability of 125 I-CAN as a novel tracer to detect cardiovascular disorders.

99mTc-zolmitriptan: radiolabeling, molecular modeling, biodistribution and gamma scintigraphy as a hopeful radiopharmaceutical for lung nuclear imaging.

Lung imaging radiopharmaceuticals are helpful agents for measuring pulmonary blood flow and allow detection of pulmonary embolism and lung cancer. The goal of this study was to develop a novel potential radiopharmaceutical for lung imaging. Zolmitriptan (a selective serotonin receptor agonist) was successfully labeled with 99mTc via direct labeling method under reductive conditions studying different factors affecting the labeling efficiency. 99mTc-zolmitriptan was obtained with a maximum labeling yield of 92.5 ± 0.61 % and in vitro stability up to 24 h. Molecular modeling was done to predict the structure of 99mTc-zolmitriptan and ensure that radiolabeling did not affect binding ability of zolmitriptan to its receptor. Biodistribution studies showed that maximum lung uptake of 99mTc-zolmitriptan was 23.89 ± 1.2 % injected dose/g tissue at 15 min post-injection and retention in lungs remained high up to 1 h, whereas the clearance from mice appeared to proceed mainly via the renal pathway. Scintigraphic images confirmed the biodistribution results showing a high resolution lung image with low accumulation of radioactivity in other organs except kidneys and urinary bladder. 99mTc-zolmitriptan is not a blood product and so it is more safe than the currently available 99mTc-MAA, and its lung uptake is higher than that of the recently discovered 123I-IPMPD, 99mTc(CO)5I and 99mTc-DHPM. So, 99mTc-zolmitriptan could be used as a hopeful radiopharmaceutical for lung scintigraphic imaging.