Recent advances in optical fiber grating sensors for detection of organic substances

The continuous development of society has led to the flourishing of environmental chemistry and biomedical fields, as well as to the research and development of novel functional materials and sensors. Some novel materials have excellent optical and biological/chemical properties and can be coupled with the optical fiber grating. The coupling between the materials and optical fiber grating can improve the performance due to the advanced materials can amplify the changing signals generated during the reaction with analytes of organic compounds. Despite the great achievements in the development of bio- and chemical-optical fiber grating sensors, there is no publicly available systematic review of the recent advances in the use of materials combined with optical fiber grating in organic substances sensing available in the literature since January 2016. Thus, we summarized the sensing principles of the bio- and chemical-optical fiber grating with and without surface plasmon resonance. We discussed the performance parameters such as sensitivity, selectivity, detection range, and low limit of detection for detection of organic substances including organic pollutants, life organics (glucose, hemoglobin, cancer markers, antibody-antigen, biotin and streptavidin, DNA, enzymes), microorganisms, and other organic substances. We analyzed the advantages and limitations of optical fiber grating sensors and presented challenges in their practical applications and future research directions.