This invention discloses a
fiber sensor, its preparation method, and its application, belonging to the field of electrochemical sensor technology. The invention provides a flexible
electrode for
continuous monitoring of
plant hormones, comprising a flexible conductive substrate and a
fiber functional layer disposed on the end face of the flexible conductive substrate; the flexible conductive substrate includes a conductive inner core and an insulating outer layer surrounding the conductive inner core, the conductive inner core being a
liquid metal gel, and the insulating outer layer comprising a
polymer; the tensile stress of the flexible conductive substrate is 1~10 kPa, the plastic deformation range is 1~10 times, and the resistance change during plastic deformation is less than or equal to 4%. The
fiber sensor provided by this invention, composed of the flexible
electrode, can match the plastic deformation of
plant growth, has low tensile stress, and maintains stable resistance during deformation, making it suitable for long-term stable monitoring of
plant hormones, offering advantages of non-destructive, long-term, and stable monitoring.