초록 ▼

An optical-based sensor for detecting the presence or amount of an analyte using both indicator and reference channels. The sensor has a sensor body with a source of radiation embedded therein. Radiation emitted by the source interacts with indicator membrane indicator molecules proximate the surfac

An optical-based sensor for detecting the presence or amount of an analyte using both indicator and reference channels. The sensor has a sensor body with a source of radiation embedded therein. Radiation emitted by the source interacts with indicator membrane indicator molecules proximate the surface of the body. At least one optical characteristic of these indicator molecules varies with analyte concentration. For example, the level of fluorescence of fluorescent indicator molecules or the amount of light absorbed by light-absorbing indicator molecules can vary as a function of analyte concentration. In addition, radiation emitted by the source also interacts with reference membrane indicator molecules proximate the surface of the body. Radiation (e.g., light) emitted or reflected by these indicator molecules enters and is internally reflected in the sensor body. Photosensitive elements within the sensor body generate both indicator channel and reference channel signals to provide an accurate indication of the concentration of the analyte. Preferred embodiments are totally self-contained and are sized and shaped for use in vivo in a human being. Such embodiments preferably include a power source, e.g. an inductor, which powers the source of radiation using external means, as well as a transmitter, e.g. an inductor, to transmit to external pickup means the signal representing the level of analyte.

대표청구항 ▼

[ What is claimed is:] [1.]1. An optical-based sensor for determining the presence or concentration of an analyte in a medium, said sensor comprising:an optically transmissive sensor body which function as an optic wave guide, said sensor body having an outer surface surrounding said sensor body;a r

[ What is claimed is:] [1.]1. An optical-based sensor for determining the presence or concentration of an analyte in a medium, said sensor comprising:an optically transmissive sensor body which function as an optic wave guide, said sensor body having an outer surface surrounding said sensor body;a radiation source in said sensor body which emits radiation within said sensor body;an indicator element having an optical characteristic that is affected by the presence or concentration of an analyte, said indicator element being positioned on said sensor body to receive radiation that travels from said radiation source, and which transmits radiation into said sensor body;a photosensitive element located in said sensor body and positioned to receive radiation within the sensor body and which emits a signal responsive to radiation received from said indicator element; andsaid sensor body being configured such that some of the radiation received by said photosensitive element is reflected internally within said sensor body before striking said photosensitive element.