Preparation, characterization, and radiolabeling of [68Ga]Nodaga-pamidronic acid: a potential PET bone imaging agent

Early diagnosis of bone metastases is crucial to prevent skeletal-related events, and for that, the non-invasive techniques to diagnose bone metastases that make use of image-guided radiopharmaceuticals are being employed as an alternative to traditional biopsies. Hence, in the present work, we tested the efficacy of a gallium-68 (68Ga)-based compound as a radiopharmaceutical agent towards the bone imaging in positron emitting tomography (PET). For that, we prepared, thoroughly characterized, and radiolabeled [68Ga]Ga-NODAGA-pamidronic acid radiopharmaceutical, a 68Ga precursor for PET bone cancer imaging applications. The preparation of NODAGA-pamidronic acid was performed via the N-Hydroxysuccinimide (NHS) ester strategy and was characterized using liquid chromatography-mass spectrometry (LC-MS) and tandem mass spectrometry (MSn). The unreacted NODAGA chelator was separated using the ion-suppression reverse phase-high performance liquid chromatography (RP-HPLC) method, and the freeze-dried NODAGA-pamidronic acid was radiolabeled with 68Ga. The radiolabeling condition was found to be most optimum at a pH ranging from 4 to 4.5 and a temperature of above 60 °C. From previous work, we found that the pamidronic acid itself has a good bone binding affinity. Moreover, from the analysis of the results, the ionic structure of radiolabeled [68Ga]Ga-NODAGA-pamidronic acid has the ability to improve the blood clearance and may exert good renal excretion, enhance the bone-to-background ratio, and consequently the final image quality. This was reflected by both the in vitro bone binding assay and in vivo animal biodistribution presented in this research

Teknetium-99 perteknetat imunoglobulin G manusia sebagai agen radiofarmaseutikal dalam pengesanan inflamasi

This study was carried out to determine the potential of technetium-99m pertechnetate Human Immunoglobulin G (***Tc.HIgG) as a radiopharmaceutical agent in the detection of inflammation site. Reduced HLgG antibody was found to be stabled at the optimal storage temperatures of -70°C and 0°C and deteriorated at 2 - N°C. The percentage of labeling of HIgG with ***Tc obtained was more than 95%. Biodistribution of ***Tc-HIgG was studied by using Sprague Dawley rats which were injected intramuscularly with turpentine to induce localized inflammation. The biodistribution of ***Tc-HIgG was determined by using immunosintigraphy (scanning) and kill and count method. Immunosintigram obtained after 4 hours post injection showed the clearest image of ***Tc-HIgG biodistribution in the inflamed muscle. The cut and count method also indicated that uptake of ***Tc-HIgG by the inflamed muscle was highest after 4 hours post injection. The pattern of ***Tc localization was different from ***Tc-HIgG. Imaging of inflamed cells using radiopharmaceutical ***Tc-HIgG, Possesses the potential to be used in the diagnosis of infection’inflammation such as in cancer or immunocompromised patients and in assessing patient’s response to the therapy of inflammatory diseases

Biodistribution study of niosomes in tumor-implanted BALB/C mice using scintigraphic imaging

The purpose of this work was to study the biodistribution of niosomes in tumor-implanted BALB/c mice using gamma scintigraphy. Niosomes were first formulated and characterized, then radiolabeled with Technetium-99 m ((99m)Tc). The biodistribution of 99mTc-labeled niosomes was evaluated in tumor-bearing mice through intravenous injection and imaged with gamma scintigraphy. The labeled complexes possessed high radiolabeling efficiency (98.08%) and were stable in vitro (>80% after 8 h). Scintigraphic imaging showed negligible accumulation in the stomach and thyroid, indicating minimal leaching of the radiolabel in vivo. Radioactivity was found mainly in the liver, spleen and kidneys. Tumor-to-muscle ratio indicated a higher specificity of the formulation for the tumor area. Overall, the formulated niosomes are stable both in vitro and in vivo, and show preferential tumor accumulation

Investigation of filler effects on the compounding of freeze-dried orodispersible tablets containing Annona muricata extract

Orally disintegrating tablets are a solid dosage form that will disintegrate rapidly within 3 minutes upon contact with saliva. Fillers or diluents are excipients that are used to make up the volume of orally disintegrating tablets, and some might act as a disintegrant or binder that will affect the physical properties of orally disintegrating tablets. The objective of this study was to formulate and evaluate physical properties of orally disin- tegrating tablets containing Annona muricata leaves extract by a freeze- drying method using different fillers at different concentrations. In this study, fifteen formulations of orally disintegrating tablets were prepared by a freeze-drying method with different fillers such as starch, lactose, microcrystalline cellulose, StarLac, and CombiLac at 5%, 10%, and 15%. The orally disintegrating tablets were evaluated for hardness, thickness, weight variation, friability, and disintegration time test. The optimum formulation was chosen and incorporated with Annona muricata leaves extract. The results obtained in this work indicated that Formulation 3, with 15% starch, was the most optimum formulation due to the shortest disintegration time (21.08 seconds ± 4.24 seconds), and all the physical tests were within the acceptable range. The orally disintegrating tablets containing Annona muricata leaves extract possessed antioxidant activity and stable at least for 3 months under 60°C and 75% RH