UV Radiation Protection by Thermal Plasma Synthesized Zinc Oxide Nanosheets

Exposure to excessive UV radiation can cause a wide range of serious effects such as sunburns, photocarcinogenesis, photoimmuno suppression, etc. Here we estimated UV radiation energy absorbed in presence of Zinc oxide nanosheets and its effect on biological model system. Ferric oxalate Actinometry was used as a reference for estimating the amount of UV energy absorbed. ZnO Nanosheets were synthesized using thermal plasma method and characterized using Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD). The average energy absorption in presence and in absence of ZnO Nanosheets was found to be 141.56 and 175.29 erg/sec-cm2 respectively. Dose reduction factor was noticed to be 0.80. Allium cepa root tip was chosen as a biological model to monitor the UV biological effects. Mitotic chromosomes of A. cepa were analyse for different condition such as UV treated, ZnO nanosheets treated and ZnO nanoparticle with UV. The mitotic index was found to be reduced in UV treated root tip as compared to control; however it has been increased in UV with ZnO nanosheets treatment. Significant difference was noticed in chromosomal abnormalities such as Vagrant anaphase, sticky metaphase, spindle abnormalities, disorganised prophase etc. The overall result indicates that ZnO nanosheets behave as UV radio protector.