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 (99mTc). 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.

Radiosynthesis of A Novel Antisense Imaging Probe Targeting LncRNA HOTAIR in Malignant Glioma

Background: Long non-coding RNA (lncRNA) HOTAIR was manifested amplifying in many human carcinomas, which could serve as a useful target for cancer therapy. The 99mTc radiolabeled antisense oligonucleotides (ASON) could visualize the expression of HOTAIR and provide a diagnostic value for malignant tumors. The aim of this study was to radiosynthesis 99mTc with HOTAIR ASON and investigate the in vivo imaging in malignant glioma xenografts.Methods: The ASON targeting lncRNA HOTAIR as well as mismatched ASON probe (ASONM) were designed and modified. The radiolabeling of 99mTc with two probes were via the conjugation of bifunctional chelator HYNIC. Then probes were purified by Sephadex G25 and tested for their radiolabeling efficiency and purity, as well as stability by ITLC and gel electrophoresis. Then the radiolabeled probes were transfected with lipofectamine 2000 for cellular uptake test and the next experimental use. Furthermore, biodistribution study and SPECT imaging were performed at different times after probes were intravenously injected in glioma tumor-bearing mice models. All data were analyzed by statistical software.Results: The labeling efficiencies of 99mTc-HYNIC-ASON and 99mTc-HYNIC-ASONM measured by ITLC were (91 ±1.5) % and (90 ±0.6) %, respectively, and the radiochemical purity were more than 89%. The probes showed good stability within 12 hours. Gel electrophoresis confirmed that the oligomers were successfully radiolabeled no significant degradation was found. Cellular uptake experiment showed that liposomes had the ability to carry probes into cells. Biodistribution study demonstrated that liposome coated 99mTc-HYNIC-ASON had significantly higher uptake in the tumor and higher T/M ratio than the mismatched group. Meanwhile, the tumor was clearly shown at 1-hour post probe injection of liposome coated 99mTc-HYNIC-ASON on SPECT/CT imaging, no tumor was seen in mismatched and blocking group.Conclusion: The liposome encapsulated 99mTc-HYNIC-ASON probe can be used in the in vivo, real-time imaging of lncRNA HOTAIR expression in malignant glioma.

Radiosynthesis of A Novel Antisense Imaging Probe Targeting LncRNA HOTAIR in Malignant Glioma.

Background: Long non-coding RNA (lncRNA) HOTAIR was manifested overexpressing and amplifying in many human carcinomas, which could serve as a useful target for cancer therapy. The 99mTc radiolabeled antisense oligonucleotides (ASON) could visualize the expression of HOTAIR and provide a diagnostic and therapeutic value for malignant tumors. The aim of this study was to radiosynthesis 99mTc with HOTAIR ASON and investigate the in vivo imaging in malignant glioma xenografts. Methods: The ASON targeting lncRNA HOTAIR as well as mismatched ASON probe (ASONM) were designed and modified. The radiolabeling of 99mTc with two probes was via the conjugation of bifunctional chelator HYNIC. Then the probes were purified by Sephadex G25 and tested for its radiolabeling efficiency and purity, as well as stability by iTLC and gel electrophoresis. Then the radiolabeled probes were transfected with lipofectamine 2000 for cellular uptake test and the next experimental use. Furthermore, biodistribution study and SPECT imaging was performed at different time after probes were intravenously injected in U87 tumor bearing nude mice models. All data were analyzed by statistical software. Results: The labeling efficiencies of 99mTc-HYNIC-ASON and 99mTc-HYNIC-ASONM measured by iTLC were (91 ±1.5) % and (90 ±0.6) %, respectively, and the radiochemical purity were more than 89%. The probes showed good stability within 12 hours for high radiochemical purity. Gel electrophoresis confirmed that the oligomers were successfully radiolabeled no significant degradation were found. Cellular uptake experiment showed that liposomes had ability to carry probes into cells. Biodistribution study demonstrated that liposome coated 99mTc-HYNIC-ASON had significantly higher uptake in the tumor and higher tumor to muscle ratio than mismatched group. Meanwhile tumor was clearly shown at 1 hours post probe injection of Liposome coated 99mTc-HYNIC-ASON on SPECT/CT imaging, compared with mismatched and blocking group. Conclusion: The Liposome encapsulated 99mTc-HYNIC-ASON probe can be radiosynthesized and used in the in vivo, real-time imaging of lncRNA HOTAIR expression in malignant glioma.

Preparation, biodistribution and dosimetry study of Tc-99m labeled N-doped graphene quantum dot nanoparticles as a multimodular radiolabeling agent

Preparation, dosimetry and biodistribution study of 99mTc-(N-GQDs) as multipurpose nanoparticles.