Smartphone based microscopic assay for detecting (oo)cyst of Giardia and Cryptosporidium

Rojina Duwal 1 , Sajeev Wagle 1 , Bhanu Neupane 2 , Basant Giri 1 1 Center for Analytical Sciences, Kathmandu Institute of Applied Sciences, Kathmandu, Nepal 2 Central Department of Chemistry, Tribhuvan University, Kathmandu, Nepal Abstract: Food borne parasitic infections has become a public health problem worldwide. Diarrhoea is recorded as one of major cause of death in Southeast- Asia. Traditional practice of eating raw or inadequately cooked food is one of the major factor that affects the pervasiveness of such parasitic infections. Vegetables usually grown using sewage, surface and river water when not properly washed or cooked becomes the vehicle for transmission of viable (oo) cysts of Giardia and Cryptosporidium. Conventional methods available for detecting (oo) cyst such as high resolution optical microscopy, PCR are highly expensive and are not suitable for field screening of large number of samples in resource limited settings. In this work, we are developing a smartphone-based microscopic assay method. Smartphone based bright field microscope uses sapphire spherical ball lens as its core component. The lens is glued on the hole of the mounting plate which is then affixed onto camera lens of smartphone using scotch double sided tape. Identification of (oo)cyst of giardia and cryptosporidium is based on morphological characterization of the specimen. In this presentation, we will present our data on the optimization of (oo)cyst extraction and concentrations steps. Since, the use of smartphone based microscope in detecting parasitic (oo) cysts in vegetable products have not yet been explored in literature, this new approach can be a promising cheaper alternative for in-field cyst detection. Key words: Giardia, Cryptosporidium, (oo)cyst ,smartphone based microscope, ball lens