Estrogen receptor targeting with genistein radiolabeled Technetium-99m as radiotracer of breast cancer: Its optimization, characterization, and predicting stability constants by DFT calculation.

Objective: Genistein is an isoflavone molecule with a high affinity for estrogen receptors (ER), which could lead to the mechanism of selective estrogen receptor modulators (SERMs) in breast cancer. Genistein labeling with technetium-99m can be a new promising strategy for diagnostic breast cancer. In this research, we evaluate the physicochemical characteristics of the [99mTc]Tc-genistein complex and describe the optimal labeling method parameters. We also calculated density functional theory to study the stability constants to support complex formation analysis (DFT). Methods: The genistein was directly labeled with 99mTc, and its stability as well as its potential for usage as a radiotracer were all investigated. DFT calculations with thermodynamic cycles to determine chemical coordination models and calculate thermodynamic constants of complex more accurately. Results: The radiochemical purity of [99mTc]Tc-genistein showed a high yield of 93.25% ± 0.30% and had good physicochemical properties. The stability of the Tc(IV)-genistein complex was confirmed by DFT calculations at a value of 99.0822. Conclusions: As a result, [99mTc]Tc-genistein could be a potential radiotracer kit for SPECT imaging of breast cancer.

Iodine-131 labeled genistein as a potential radiotracer for breast cancer.

OBJECTIVE: Genistein is an isoflavone compound that has been proven to have anticancer activity and is capable of binding to estrogen ß receptors with Selective Estrogen Receptor Modulators (SERMs) properties, and has a strong affinity to inhibit the development of cancer cells. This study is to determine the optimum conditions of the reaction in the synthesis process of compounds labeled 131I-genestein which can be potential for application of breast cancer diagnosis. METHODS: Synthesis of 131I-Genistein compound labeling using the Chloramine-T iodination method. This method uses several parameter optimizations, including: pH conditions, the amount of chloramine-T oxidizer and sodium metabisulfite reducing agent. The radiochemical purity of the 131I-Genistein compound was determined using thin layer chromatography TLC-SG F254, and measured by SCA (Single Channel Analyzer). The radiochemical purity of labeled compounds must fulfill the requirements of the United States of Pharmacopeia. RESULTS: Optimization of the synthesis conditions of the 131I-Genistein compound was obtained at pH 8, the amount of chloramine-T 0.225 mg, and the amount of Na-Metabisulfite 0.342 mg, with 30 min reaction time. This optimum condition produces radiochemical purity of 95.02 ± 0.76%. CONCLUSION: Products labeled 131I-Genistein meet radiochemical purity requirements according to USP requirements. The labeled compound is expected to be able to be used to detect breast cancer through a binding mechanism with estrogen receptors ß.

The optimization method for synthesis of technetium-99m-luteolin as radiotracer in the development of cancer drugs from flavonoid.

The aim of this study is to find the optimum conditions of labeling luteolin flavonoid compounds with technetium-99m (99mTc) to meet the purity requirements stated in the United States Pharmacopeia. This compound is expected to be a potential radiotracer compound for diagnosing cancer. The optimization method in labeling luteolin with technetium determines the parameters such as pH, SnCl2.2H2O, genistein concentration, and incubation time. Optimization results of Technetium-99m-luteolin labeling obtained optimum pH conditions 8, the amount of SnCl2.2H2O as a reducing agent 60 µL, the optimum amount of luteolin 6 mg/ml, and the optimum incubation time is 30 min. This optimum condition obtained a 99mTc-Luteolin radiochemical purity yield of 94.15%. The radiochemical purity percentage of the 99mTc-Luteolin compound has fulfilled the requirements listed at United States Pharmacopeia, which is ≥90%.

Technetium-99m-labeled genistein as a potential radical scavenging agent.

The purpose of this study was to determine the optimum conditions for labeling genistein compounds with technetium-99m (99mTc) radionuclides and the percentage of purity obtained in accordance with the requirements of the United State Pharmacopeia. The method used is optimization of several parameters including pH, SnCl2.2H2O as reducing agents, genistein concentration, and incubation time. The results showed that the optimum conditions for labeling 99mTc-Genistein were obtained under conditions of pH 8, the amount of SnCl2.2H2O reducing agents was 30 µg, 0.5 mg genistein, and in 10 min. The optimization of this condition resulted in radiochemical purity in the labeling of 99mTc-Genistein compounds at 95.43% ± 0.85%. The radiochemical purity of the labeling of 99mTc-Genistein compounds has met the requirements of the United State Pharmacopeia as a compound marked for diagnosis of more than 90%.