In this work, an efficient absorber (biosensor) based on the combinations of graphene – plasmonic - black phosphorous configurations is proposed and investigated. The presented absorber is considered to operate based on the plasmon-induced transparency (PIT) effect. The presented absorber is based on various layers of graphene, phosphorene and gold in the ring and plate shapes. In the bio-sensing application, the analyte would be inserted in the upper layer while being in contact with the incident light wave. By considering the PIT effect, the absorber would be further improved (improving the absorption's peak value). In order to fulfill the improvement, effects of structural parameters (R1, R2, R3, R4, h1, h2, h3) and chemical potential(Ef) would be investigated. After the improvement process, the structure would be utilized as a biosensor for detection the Glucose concentrations in blood samples. By detecting Glucose concentrations in blood samples, physicians can diagnose diabetes in early stages. Finally, the sensitivity factor, figure of merit (FOM), full width at half maximum (FWHM) and Q-Factor of 2686.5 nm/RIU, 134.325 RIU−1, 20 nm and (58.5–76.5) would be achieved, respectively. As a result, the proposed absorber (biosensor) can be a remarkable and great candidate for bio-sensing applications in optical integrated circuits.