Design of integrated optical Mach-Zehnder interferometer biosensor for ideal surveillance rapid diagnostic test

Dengue is an emerging global health problem. There is still no cure or vaccine for dengue infection. As a result, disease surveillance is the only method to reduce the disease burden effectively through virus containment. Dengue diagnosis test plays a crucial role in disease surveillance due to the complexity of dengue pathogenesis. With the aid of immunochromatography based rapid diagnostic test (ICT-RDT), dengue infection can be diagnosed accurately. However, the major drawbacks of this convenient RDT are the lack of accuracy (range from 11% to 99%) and high cost per test (>RM 40). As a result, an ideal surveillance RDT is of high demand with the characteristic of high accuracy and low cost per test in particular. In this paper, integrated optical Mach-Zehnder interferometer (IO-MZI) biosensor is proposed to achieve this ideal surveillance RDT. The design of IO-MZI had been carried out by using three dimensional finite difference beam propagation method (3D-FD-BPM). The estimated detection limit of IO-MZI biosensor is found to be 5.448×10^-7 RIU which is sufficient for dengue diagnostic.