Evaluation of gold nanoparticles coated sandwich Elisa as innovative diagnosis for human Bancroftian Filariasis

This study compared the traditional sandwich ELISA and nano-sandwich ELISA methods for diagnosis of lymphatic filariasis. With the ability to interact with matter at the nanoscale, the development of nanotechnology architecture and materials could potentially extend molecular detection beyond the limits of conventional diagnostic modalities. This study included 142 subjects who were classified into; filarial diseased, other parasitic diseased and healthy control groups. Firstly, thick blood film was done for all subjects under study and their sera were obtained and preserved. A prepared sitarial antigen was injected into a rabbit to obtain polyclonal antibodies. That rabbit serum was purified, then pure IgG was obtained and a part of it was conjugated with gold nanoparticles. Conventional ELISA and nano-ELISA were done for patient's serum to detect circulating filarial antigen. Examination of blood film for microfilaria resulted in that; 5.1 % of all patients were positive however 94.9 % were negative. In comparison between ELISA and nano-ELISA readings, it was obvious that nano-ELISA is advantageous than traditional ELISA in all cases. The sensitivity, specificity, positive predictive value and negative predictive value of ELISA were 90.7 %, 75 %, 84.8 % and 84 % respectively. While by using nano-ELISA, they were 95.1%, 87.5 %, 92.9 % and 91.3 % respectively. It was concluded that using nano-sandwich ELISA of the serum samples for detection of circulating filarial antigen in patients infected with W. bancrofti gave higher sensitivity and specificity than conventional ELISA, as proved by statistical study