We report our latest investigations on 2D-layered materials integrated fiber optic configurations for chemical and labelfree biosensing applications. Due to the favorable combination of exceptionally high surface-to-volume ratio and excellent optical and biochemical properties, graphene oxide (GO) and black phosphorus (BP) were deposited on fiber grating device as the bio-photonic linking layer to provide the remarkable platform for light-matter interface and affinity binding interaction. We developed a novel in-situ layer-by-layer (i-LbL) deposition technique based on chemicalbonding associated with physical-adsorption for the deposition of 2D materials. This approach secured high-quality 2D materials deposition on cylindrical fiber with strong adhesion as well as a prospective thickness control. By taking advantage of i-LbL deposition, the unique optical tunable features and polarization-selective characteristics have been experimentally observed. Several 2D material integrated fiber optic sensors have been proposed for chemical and biochemical applications, such as GO-long period grating (GO-LPG) based Hemoglobin sensor, GO dual-peak LPG (GO-dLPG) based label-free immunosensor, and the first BP fiber optic chemical sensor based on BP-tilted fiber grating (BP-TFG). We believe that 2D material integrated fiber optic configurations open the path as highly sensitive biophotonic platform for food safety, environmental monitoring, clinical diagnostics and biomedical applications.