In vitro and in vivo biocompatibility study of polyacrylate TiO2@Ag coated nanoparticles for the radiation dose enhancement.

To enhance the efficacy of radiation therapy, functionalised core-shell nanoparticles (CS NPs) are used as a radiosensitizer. These NPs can act as a therapeutic agent and carrier for other therapeutic agents. In this study, the first poly-acrylic acid modified silver-coated titanium dioxide NPs were fabricated to evaluate the radiation dose enhancement within the human tissue equivalent polymer gel after investigating the biocompatibility. Macrophage cell line and rats model were used for in vitro and in vivo study respectively. Two different beam qualities were applied to quantify the radiation dose enhancement with different concentrations of NPs in the polymer gel. The dose enhancement factors (DEFs) indicated that these biocompatible CS NPs are more effective for the radiation dose enhancement at low energy x-rays (80 kV) as compared to the high energy gamma (1.25 MeV Co60). These results suggested that functionalised core-shell silver-coated titanium dioxide NPs have great potential as a radiosensitizer in radiation therapy.

Impact of brachytherapy applicators geometry on dose distribution in gynaecological cancer.

OBJECTIVE: To evaluate the efficacy of suitable applicators for intracavitary brachytherapy to treat cervical cancer. METHODS: This study was conducted at the Bahawalpur Institute of Nuclear Medicine and Oncology, Bahawalpur, Pakistan, in February 2014. Dose distributions for Fletcher and ring applicators were analysed at target points according to recommended protocols using Abacus software. The doses to the organs at risk, i.e. bladder and rectum, were also focused. SPSS 16 was used for data analysis. RESULTS: A total of 40 patients' plans were considered. The mean absorbed dose at target point A was 6.87±0.201Gy in case of Fletcher applicator (p=0.082) and 6.79±0.107Gy in case of ring applicator (p=0.001). Absorbed dose at the target point was significantly higher for the Fletcher type applicators as compared to the ring applicators. However, the amount of doses at bladder and rectum were smaller for the Fletcher applicators. CONCLUSIONS: Fletcher applicator was more effective in achieving a better dose distribution in gynaecological malignancies, resulting in better treatment outcome.