Analytical exploration of wave theory based highly sensitive fiber optic bio-sensor irradiated by BG beam for early diagnosis of dengue infection

An analytical study of wave theory-based multilayered SPR-based fiber optic biosensor by shinning Bessel-Gauss (BG) beam is proposed here for early diagnosis of dengue infection. At first, this wave theory-based analytical model shined by Gaussian (G) beam is validated with the already reported experimental data, where the obtained results are in good accord with the experimental findings presented by Y. M. Kamil et al. in 2018. So, it affords the experimental confirmation of the validity of the proposed theory. The enhancement in sensitivity is 1.99 times ascertained by employing G beam for our proposed structure at a spectral sensitivity of 10.008 nm/nM. This theoretical investigation has then been extended utilizing the BG beam, where the observed sensitivity is increased to 59,602.00 dB/RIU and 20.016 nm/nM with a resolution of 1.68 × 10^–7, which is 3.98 times higher than the referred published work. Here, the limit of detection is 0.06 pM with a minimum change in transmitted output power of 0.8658 milliwatt/RIU. When the DENV-II E protein concentration ranges from 0.08 pM to 0.6 nM, higher spectral shifts are observed. Consequently, enhancements in sensitivity and resolution can be achieved at reduced concentrations, paving the idea of diagnosis of dengue infection at an early stage.