Preparation, biological evaluation and radiolabeling of [99mTc]-technetium tricarbonyl procainamide as a tracer for heart imaging in mice

This study focuses on the synthesis and preliminary bio-evaluation of [99mTc]-technetium tricarbonyl procainamide ([99mTc]-technetium tricarbony PA) as a viable cardiac imaging agent. The compound, [99mTc]-technetium tricarbony PA, was synthesized by labelling procainamide with a [99mTc]-technetium tricarbonyl core, yielding a high radiochemical yield and radiochemical purity of 98%. Under optimal circumstances, high radiochemical yield and purity were obtained utilizing [99mTc]-technetium tricarbonyl core within 30 min of incubation at pH 9, 200 µg substrate concentration, and 100 °C reaction temperature. The heart showed a high absorption of 32.39 ± 0.88% of the injected dose/g organ (ID/g), confirming the suitability of [99mTc]-technetium tricarbonyl PA as a viable complex for heart imaging.

Enhancement of the thermal and physicochemical properties of styrene butadiene rubber composite foam using nanoparticle fillers and electron beam radiation

This study investigates the physicochemical and thermal properties of styrene–butadiene rubber (SBR) nanocomposite foam. Nano-calcium carbonate (CaCO3) was prepared from eggshells (ESs) waste. Sponge rubber nanocomposites were prepared and were irradiated by electron beam (EB) radiation at 25, 75, and 150 kGy. Their physicochemical properties, including foam density, compression set (CS), hardness, abrasion loss, and expansion ratio, and their thermal stability were investigated. The physicochemical properties were enhanced by adding 2.5 phr of a foaming agent. Among the composites examined, the foam composites containing nano-CaCO3 had the lowest CS, abrasion loss, and expansion ratio and the highest hardness and foam density. The results confirmed that the thermal stability was improved by incorporating nano-CaCO3 into the SBR foam and as the radiation dose increased. The sponge containing nanoclay demonstrated an intermediate behavior, whereas that with CaCO3 nanoparticles showed low average cell diameter and size and high cell wall thickness. The radiation process enhanced the foam density, CS, abrasion loss, hardness, and thermal property of the developed nanocomposites by inducing the formation of intermolecular crosslinks within the composite matrix. The results showed that physicochemical properties improved by increasing the radiation dose at 25 kGy.

Radioiodination of balsalazide, bioevaluation, and characterization as a highly selective radiotracer for imaging of ulcerative colitis in mice

This work focuses on tracking ulcerative colitis in mice. High labeling yield and radiochemical purity were achieved for the formation of a [^125/131 I]balsalazide radiotracer at optimum conditions of oxidizing agent content (chloramines-T [Ch-T], 75 μg), substrate amount (100 μg), pH of reaction mixture (6), reaction time (30 min), and temperature (37°C), using radioactive iodine-125 (200-450 MBq). The radiolabeled compound, [^125/131 I]balsalazide, was stable in serum and saline solution during 24 h. Balsalazide is acting as a peroxisome proliferator-activated receptor (PPARγ). Biodistribution studies were carried in normal and ulcerated colon mice. High uptake of 75 ± 1.90% injected dose/g organ (ID/g) observed in ulcerated mice confirmed the suitability of [¹³¹ I]balsalazide as a novel radiotracer for ulcerative colitis imaging in mice.

Preparation, characterization, and bioevaluation of 99mTc-famotidine as a selective radiotracer for peptic ulcer disorder detection in mice

This work focuses on tracking peptic ulcer localized in mice. The formation of a [99mTc]dithiocarbamate of famotidine complex at optimum conditions of reaction temperature (37 °C), reaction time (30 min), pH of the reaction mixture (5), amount of substrate (100 µg), amount of reducing agent (tin (II) content, 50 µg), was achieved using radioactive Tc-99m (250–400 MBq), with labelling yield of 98% and high radiochemical purity. The in-vitro stability of [99mTc]dithiocarbamate of famotidine complex was shown to be high in rat serum for up to 8 h. Normal and ulcerated mice were used in biodistribution studies. Famotidine works by blocking histamine-2-receptor antagonists (H2RAs). The high absorption of [99mTc]dithiocarbamate of famotidine complex in stomach in amount of 27.15% injected dose/g organ (ID/g) observed in ulcerated mice for up to 24 h demonstrated its usefulness as a novel radiotracer for stomach imaging.

Radioiodinated esomeprazole as a model for peptic ulcer localization

This work focuses on tracking stomach ulcer localized in mice. High labeling yield and radiochemical purity were achieved for the formation of a [125I]esomeprazole radiotracer at optimum conditions of oxidizing agent content (chloramines-T (Ch-T), 100 μg), substrate amount (Esom, 100 μg), pH of reaction mixture (6), reaction time (30 min) and temperature (37 °C), using radioactive iodine-125 (200–450 MBq). The radiolabeled compound, [125I]esom, was stable in serum and saline solution during 24 h. Esom is acting as a histamine-2-receptor antagonist (H2RA). Biodistribution studies were carried in normal and ulcerated mice. High uptake of 78.12 ± 0.80% injected dose/g organ (ID/g) observed in ulcerated mice confirmed the suitability of [125I]esomeprazole as a novel radiotracer for stomach imaging.

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

One of the most famous techniques for stomach ulcer imaging is the nuclear imaging technique. We aim to focus on the synthesis of 125I-cimetidine (125I-cim) as an agent for peptic ulcer imaging. Cimetidine was labeled with Iodine-125 using a different oxidizing agent (Ch-T, NBS). All factors affecting the labeling yield were optimized. The radiochemical yield of 125I-cim was 98 ± 0.22% at optimum conditions. In vitro stability, in vivo biodistribution of 125I-cimetidine was studied in three groups: control group, pretreated group, and ulcer bearing group. In vivo biodistribution studies of 125I-cim revealed high uptake in the stomach ulcer, reaching about 75.4 ± 1.2% ID/g at 15 min post-injection, than pretreated groups compared to the control. The results showed the suitability of using 125I-cimetidine for stomach ulcer imaging.

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.

Radioiodinated famotidine as a new highly selective radiotracer for peptic ulcer disorder detection, diagnostic nuclear imaging and biodistribution

Famotidine was labeled with iodine-125 to obtain 125I-famotidine (125I-fam) as an agent for ulcer imaging. The radiochemical yield of 125I-famotidine reached approximately 98.5 ± 0.23% at optimum conditions of pH, oxidizing agent, reaction time and the amount of substrate. 125I-fam was stable for 48 h. Different chromatographic techniques were used to determine the radiochemical yield and purity. Intravenous biodistribution studies of 125I-fam revealed high concentration in the stomach ulcer, reaching about 65.9 ± 0.28% of the total injected dose at 30 min post injection. This concentration of 125I-fam in stomach ulcer makes this agent promising for stomach ulcer imaging.