Investigation of Biological and Prooxidant Activity of Zinc Oxide Nanoclusters and Nanoparticles oleh Iliana A. Ivanova, Elitsa L. Pavlova, Anelyia s. Kostadinova, Radostina D. Toshkovska, lLyubomira D. Yocheva, kh. El-Sayed, Mohamed A. Hassan, Heba Elsayed ElZorkany, Hisham Ali Elshoky