In this study, zinc oxide (ZnO) nanorod arrays were synthesized using a simple hydrothermal reaction on a ZnO seeds/
ITO substrate and applied for the fabrication of enzymatic glucose sensor. ZnO nanorod matrix provided a favourable
environment for the immobilization of glucose oxidase (GOx) and introduced a shuttling way for electronic communication
between GOx and electrode. The performance of different aspect ratio of ZnO nanorods that was produced by varying
hydrothermal reaction time was studied. The aspect ratio of ZnO influenced the GOx enzyme immobilization. The
morphology and structure of prepared ZnO nanorods were characterized by employing scanning electron microscopy
(SEM), and X-ray powder diffraction (XRD). Electrochemical measurements of the sensor showed a reproducible sensitivity
of 2.06 μA/cm2
mM for ZnO matrix grown for 4 h with the aspect ratio of 8.0.
Gold nanoparticles (AuNPs) have been extensively investigated as dose enhancement agent to increase the lethal dose to the tumours while minimizing dose to the normal tissue. Their intriguing properties and characteristics such as small size and shape provide favorable option in increasing radiotherapy therapeutic efficiency. In this study, the effects of AuNPs size on the dose enhancement effects irradiated under megavoltage photon beams were investigated. The study was conducted in-vitro on HeLa cells using AuNPs of 5 nm and 15 nm sizes. The cells samples were incubated with AuNPs and irradiated with photon beam of energy 6 MV and 10 MV at 100 cm SSD and 10 cm x 10 cm field size. Clonogenic assay were performed to observe the dose enhancement effects on cell survival. Dose enhancement factor (DEF) were extrapolated and evaluated from the cell survival curves. The results show that both sizes of AuNPs produce dose enhancement with the larger size AuNPs of 15 nm produce more dose enhancement compare to 5 nm AuNPs for 6 MV photon beam. Dose enhancements were observed for 10 MV photon beams but DEF for both sizes AuNPs shows no differences. In conclusion, larger size AuNPs produce higher dose enhancement compare to small size of AuNPs which conclude that nanoparticles size is important factor that need to be taken into account for AuNPs to be applied in radiotherapy.