International Journal of Medicine and Medical Sciences Vol. 2(1), pp. 053-058, January, 2012. Available online at http://internationalscholarsjournals.org (ISSN: 2167-0404) © International Scholars Journals Full Length Research Paper Cytotoxic Effects of Zinc Oxide Nanoflakes (ZNO NFS) in Human Muscle Carcinoma Syed M. Usman Ali 1, 4 , M. Fakhar-e-Alam 1, 2 , Z.Wazir 2 ,M. Kashif 3 , M. Atif 2 , Magnus Willander 1 and W. A. Syed 2 1 Physical Electronics and Nanotechnology Division, Department of Science and Technology, Campus Norrköping, Linköping University, SE-60174 Norrköping, Sweden 2 Department of Physics, Faculty of Basic and Applied Sciences, International Islamic University, Islamabad 3 Nano Biochip Research Group, Institute of Nano Electronic Engineering (INEE), University Malaysia Perlis (UniMAP), 01000 Kangar, Perlis, Malaysia. 4 Department of Electronic Engineering, NED University of Engineering and Technology, Karachi-75270, Pakistan Received October 29, 2011; Accepted January 24, 2012 Cytotoxicity of bare and conjugation of Tween-80 capsulated nanomaterials e.g. zinc oxide nanoflakes (ZnO NFs), iron oxide nanoparticles (Fe 2 O 3 NPs) was examined in dark as well as under light exposure in cell model of immature human muscle carcinoma (RD) via microinjection and free standing drug delivery system. ZnO NFs were grown on the tip of a capillary and characterized by applying atomic force microscopy (AFM) technique and the tip was used as pointer to insert chemicals into cell to visualize/assess the emission of reactive oxygen species (ROS) especially from mitochondria. Bare and conjugated ZnO NFs with δ-aminolevulinic acid (ALA) were irradiated /excited with UV light after cellular uptake, reactive oxygen species were generated. We deduct that ROS is damaging mitochondria resulting in cell necrosis within few minutes. ZnO NFs are not biosafe and have significant toxic effects for both normal as well as cancer cell especially for rhybdomyosarcoma cell line (RD). Keywords: atomic force microscopy (AFM), δ-aminolevulinic acid (ALA), reactive oxygen species (ROS), human muscle carcinoma (RD cells), Zinc Oxide nanoflakes ZnO NFs. INTRODUCTION Current research suggests that photodynamic therapy (PDT) is encouraging, minimally invasive treatment modality for premalignant, malignant lesions requiring the interaction of light (UV-Visible), photosensitizer, and singlet oxygen [1]. The basic principle of PDT is to take a chemical and excite with light (Laser) of specific wavelength matchable to absorption peak of chemical drug, leads to the energization of chemicals causing cell death [2]. Photosensitizer (PS) complexed with nanomaterials (NMs) activated by UV light (240 nm of light wavelength) results in tissue necrosis by direct tumor killing effect, vascular blockade, most importantly Corresponding author’s E-mail: uashah68@hotmail.com singlet oxygen release from mitochondria. [3-5]. Nanotechnology or nanoscience is “the design, characterization, production, and application of structures, devices, and systems by controlled manipulation of size and shape at the nanometer scale (atomic, molecular, and macromolecular scale) which produces structures, devices, and systems with at least one novel/superior characteristic or property” [6]. In addition, Nanomedicine and nanotechnology, have introduced numerous NPs of variable chemistry and architecture for cancer diagnostics and treatment, involving engineering multifunctional devices with dimensions at the nanoscale [7]. Zinc oxide nanoflakes (ZnO NFs) and zinc oxide nanowires (ZnO NWs) are emerging milestones in PDT ongoing research with tremendous multiple clinical applications, diagnostic as well as antitumoricidal, in many microbial nonmicrobial