METHODS: Negatively charged acrylic microspheres were labeled with 152Sm ions through electrostatic interactions. In another formulation, the Sm-labeled microsphere was treated with sodium carbonate solution to form the insoluble 152Sm carbonate (152SmC) salt within the porous structures of the microspheres. Both formulations were neutron-activated in a research reactor. Physicochemical characterization, gamma spectrometry, and radiolabel stability tests were carried out to study the performance and stability of the microspheres.
RESULTS: The Sm- and SmC-labeled microspheres remained spherical and smooth, with a mean size of 35 µm before and after neutron activation. Fourier transform infrared (FTIR) spectroscopy indicated that the functional groups of the microspheres remained unaffected after neutron activation. The 153Sm- and 153SmC-labeled microspheres achieved activity of 2.53 ± 0.08 and 2.40 ± 0.13 GBq·g-1, respectively, immediate after 6 h neutron activation in the neutron flux of 2.0 × 1012 n·cm-2·s-1. Energy-dispersive X-ray (EDX) and gamma spectrometry showed that no elemental and radioactive impurities were present in the microspheres after neutron activation. The retention efficiency of 153Sm in the 153SmC-labeled microspheres was excellent (~99% in distilled water and saline; ~97% in human blood plasma), which was higher than the 153Sm-labeled microspheres (~95% and ~85%, respectively).
CONCLUSION: 153SmC-labeled microspheres have demonstrated excellent properties for potential application as theranostic agents for hepatic radioembolization.
AIM: To develop a neutron-activated, biodegradable and theranostics samarium-153 acetylacetonate (153SmAcAc)-poly-L-lactic acid (PLLA) microsphere for intraarterial radioembolization of hepatic tumors.
METHODS: Microspheres with different concentrations of 152SmAcAc (i.e., 100%, 150%, 175% and 200% w/w) were prepared by solvent evaporation method. The microspheres were then activated using a nuclear reactor in a neutron flux of 2 × 1012 n/cm2/s1, converting 152Sm to Samarium-153 (153Sm) via152Sm (n, γ) 153Sm reaction. The SmAcAc-PLLA microspheres before and after neutron activation were characterized using scanning electron microscope, energy dispersive X-ray spectroscopy, particle size analysis, Fourier transform infrared spectroscopy, thermo-gravimetric analysis and gamma spectroscopy. The in-vitro radiolabeling efficiency was also tested in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.
RESULTS: The SmAcAc-PLLA microspheres with different SmAcAc contents remained spherical before and after neutron activation. The mean diameter of the microspheres was about 35 µm. Specific activity achieved for 153SmAcAc-PLLA microspheres with 100%, 150%, 175% and 200% (w/w) SmAcAc after 3 h neutron activation were 1.7 ± 0.05, 2.5 ± 0.05, 2.7 ± 0.07, and 2.8 ± 0.09 GBq/g, respectively. The activity of per microspheres were determined as 48.36 ± 1.33, 74.10 ± 1.65, 97.87 ± 2.48, and 109.83 ± 3.71 Bq for 153SmAcAc-PLLA microspheres with 100%, 150%, 175% and 200% (w/w) SmAcAc. The energy dispersive X-ray and gamma spectrometry showed that no elemental and radioactive impurities present in the microspheres after neutron activation. Retention efficiency of 153Sm in the SmAcAc-PLLA microspheres was excellent (approximately 99%) in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.
CONCLUSION: The 153SmAcAc-PLLA microsphere is potentially useful for hepatic radioembolization due to their biodegradability, favorable physicochemical characteristics and excellent radiolabeling efficiency. The synthesis of the formulation does not involve ionizing radiation and hence reducing the complication and cost of production.
OBJECTIVE: In the current study, aqueous extract of Thymus vulgaris (T. vulgaris) was used to synthesize the AgNPs using green synthesis techniques followed by checking the effectiveness and various biological activities of these AgNPs.
METHODS: At first, the plant samples were proceeded for extraction of aqueous extracts followed by chromatography studies to measure the phenolics and flavonoids. The synthesis and characterization of AgNPs were done using green synthesis techniques and were confirmed using Fourier transform infra-red (FT-IR) spectroscopy, UV-visible spectroscopy, scanning electron microscope (SEM), zeta potential, zeta sizer and X-Ray diffraction (XRD) analysis. After confirmation of synthesized AgNPs, various biological activities were checked.
RESULTS: The chromatography analysis detected nine compounds accounting for 100% of the total amount of plant constituents. The FT-IR, UV-vis spectra, SEM, zeta potential, zeta sizer and XRD analysis confirmed the synthesis of AgNPs and the variety of chemical components present on the surface of synthesized AgNPs in the plant extract. The antioxidant activity of AgNPs showed 92% inhibition at the concentration of at 1000 µg/mL. A greater inhibitory effect in anti-diabetic analysis was observed with synthesized AgNPs as compared to the standard AgNPs. The hemolytic activity was low, but despite low concentrations of hemolysis activity, AgNPs proved not to be toxic or biocompatible. The anti-inflammatory activity of AgNPs was observed by in-vitro and in-vivo approaches in range at various concentrations, while maximum inhibition occurs at 1000 µg (77.31%).
CONCLUSION: Our data showed that the potential biological activities of the bioactive constituents of T. vulgaris can be enhanced through green synthesis of AgNPs from T. vulgaris aqueous extracts. In addition, the current study depicted that AgNPs have good potential to cure different ailments as biogenic nano-medicine.