Nghiên cứu đánh dấu kháng thể đơn dòng bevacizumab với đồng vị phóng xạ Tc-99m dùng trong chụp hình miễn dịch phóng xạ ung thư

Abstract

Objective: This paper describes a method for the radiolabeling of monoclonal antibody bevacizumab in the production of ^99mTc-bevacizumab radiopharmaceutical in the radioimmunoscintigraphy (RIS). Bevacizumab is a humanized monoclonal and recombinant antibody that is an anti-vascular endothelial growth factor (VEGF) and effective in blocking the process of angiogenesis. Subject and method: Bevacizumab was labeled with radioisotope ^99mTc by direct method using stannous chloride as reductant. The labeling optimization was conducted such as pH, temperature, time, molar ratio. The radioimmunoconjugates were tested for radiolabeling yield, radiochemical purity and stability. Result: The results of the optimized study showed that bevacizumab was labeled with ^99mTc in 0.5M phosphate buffer, pH = 7.5 at room temperature for 15 minutes. Radiolabeling yields of labelled bevacizumab were more than 95%, radiochemical purity reached 98% and stability for 24 hours. Conclusion: The conjugation of ^99mTc-bevacizumab initially met the required criteria of radiopharmaceutical and could be used for preclinical evaluations.