Advances in sensor materials and optoelectronics have enabled new optical sensors for use in biotechnology, food and beverage processing, and more. These fiber optic chemical sensors work by trapping an oxygen-sensitive fluorophore or pH indicator dye in a sol-gel host matrix that is applied to an adhesive patch, the tip of a fiber, or a flat substrate such as a cuvette. The indicator materials change optical properties in response to analytes in their environment, and…