A new biophotonic sensor based on photonic crystal (PC) has been designed for the detection of creatinine concentration in blood, and is considered an important small molecule biomarker of renal dysfunction.

Tuberculosis is one of the most widespread infectious and deadliest diseases in the world. The death percentage is larger than that in the case of the current Coronavirus. Bio-photonic sensors represent a promising option for developing reliable, simple, and affordable tools for the effective detection of tuberculosis. In this paper, a novel design of an optical biosensor will be used as a tuberculosis detector based on a resonance cavity with high sensitivity in one-dimensional photonic crystals demonstrated theoretically. The results show that the increase of the defect layer thickness shifts the defect mode to a longer wavelength region. Besides, it is shifted to a shorter wavelength region via the increase of the incidence angle. The change in thickness of the defect layer and incident angle of light cause an optimization for our suggested structure and the sensitivity reaches 1390 nm/RIU. Our structure is very simple for industrial design.

The present research is focused on the externally tunable defect mode properties of a one dimensional (1D) defective photonic crystal (DPhC) for fast detection of cancerous brain tumors. The proposed design has utilized conventional 1D DPhC whose cavity is coated with SiO2 nanoparticles embedded in a superconducting material layer called a nanocomposite layer. The purpose of a nanocomposite superconducting layer is to induce temperature dependent external tuning of the defect mode inside PBG, in addition, to changing in the angle of incidence. The inclusion of a nanocomposite layer also improves the interaction between light and different brain tissue samples under examination. In order to investigate the transmission properties of the proposed structure the transfer matrix formulation in addition to the MATLAB computational tool has been used. First, we have chosen the optimized internal parameters at normal incidence to obtain the maximum performance of the design. Secondly, the effect of change in angle of incidence has been studied to further increase the performance by means of sensitivity, quality factor, the figure of merit and limit of detection to ensure external tuning of defect mode. After achieving a maximum value of sensitivity (4139.24 nm/RIU) corresponding to a sample containing a wall of brain tissues at θ = 63° we have further investigated the effect of change in temperature of nanocomposite layers on the position and intensity both of the defect mode inside PBG. We have found that the increase in temperature results in minute changes in sensitivity but a significant increase in the intensity of defect mode which is highly required in any photonic biosensing design. The findings of this study may be very useful for designing various bio-sensing structures which could have a significant and decisive role in the field of biomedical applications.

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In this manuscript one-dimensional (1D) photonic biosensor (PQ) N GDG(PQ) N composed of phase change material (PCM) germanium antimony telluride (GST) has been studied in visible region of electromagnetic spectrum. This design is capable of label free recognition of reproductive hormones of female which are significant during reproductive process such as menstruation and parturition. The proposed structure is composed of an air cavity separated by two buffer layers of GST material. The GST buffer layers have been used to improve the sensing performance of the structure. The modified cavity associated with buffer GST layers is sandwiched between two 1D photonic structures (PS) (PQ) N . Both 1D PS are consisted of alternate material layers of SiO2 and Si of period 5. The transmission spectra of proposed design have been obtained by using transfer matrix method and MATLAB software. In this work the performance of the devise has been investigated for normal and oblique incidence corresponding to TE wave only under the influence of change of phases of GST. The mainstay of this research is focused on the tunable performance of proposed bio-sensing design due to switching between amorphous phase (aGST) and crystalline phase (cGST) of GST. Moreover how the change in the thickness of cavity region as well as angle of incidence corresponding to TE wave affects the performance of the design has also been studied. The sensitivity, quality factor and figure of merit values of the design have also been studied to get deep insight about the sensing capabilities of the proposed design under the influence of crystalline and amorphous phases of GST. Thus due to simple architecture and excellent switchable and reconfigurable characteristics, our structure works efficiently in industrial and biomedical refractive index based sensing applications.