Abstract: An implantable biosensor for detecting an analyte in vivo in body fluids comprises an analyte-sensitive hydrogel filament chemically configured to vary its displacement volume according to changes in concentration of an analyte, such as glucose, in a patient's body fluid. A photometric displacement transducer placed inside the biosensor is configured to quantifiably detect changes in the displacement volume of the hydrogel filament, such as by detecting the light intensity on a photoreceptor arranged to receive light of varying intensity depending upon the displacement of the hydrogel filament. A battery powered telemeter operably engaged to the photometric displacement transducer sends a radio data signal representing glucose concentration level to a receiver containing an alarm system. The alarm system can automatically notify a person that the analyte level is outside desired predetermined parameters, and/or to automatically inject an agent to counteract the adverse analyte levels.

Abstract: An implantable chip biosensor for detecting an analyte in vivo in body fluids comprises an analyte-sensitive hydrogel slab chemically configured to vary its displacement volume according to changes in concentration of an analyte, such as glucose, in a patient's body fluid, the slab being disposed in a groove in a support block. The biosensor chip is ‘read’ by an external scanner configured to quantifiably detect changes in the displacement volume of the hydrogel slab. The support block is made of rigid or semi-rigid support material to restrain expansion of the hydrogel in all but one dimension, and the groove has one or more openings covered with a semipermeable membrane to allow contact between the patient's body fluid and the hydrogel. The scanning means may be any type of imaging devices such as an ultrasound scanner, a magnetic resonance imager (MRI), or a computerized tomographic scanner (CT) capable of resolving changes in the slab's dimensions.

Abstract: The penicillin biosensor (10) has a pH-sensitive polymeric hydrogel (30) in a rigid enclosure (20). The hydrogel includes an immobilized enzyme such as penicillinase. The enzyme catalyzes a chemical reaction consuming penicillin and producing penicillic acid. The hydrogel changes its osmotic pressure in proportion to the concentration of the penicillic acid. By measuring the change in osmotic pressure with a pressure transducer (40), the biosensor (10) is able to accurately measure the concentration of penicillin. A battery (64) powered monitoring device, connected to the biosensor (10) through electrical wires, is operably programmed to display the penicillin concentration in a computer (62) as well as to activate LED or buzzer as an alert in case that the measured concentration of penicillin is over the threshold concentration.

Abstract: An implantable chip biosensor for detecting an analyte in vivo in body fluids comprises an analyte-sensitive hydrogel slab chemically configured to vary its displacement volume according to changes in concentration of an analyte, such as glucose, in a patient's body fluid, the slab being disposed in a groove in a support block. The biosensor chip is ‘read’ by an external scanner configured to quantifiably detect changes in the displacement volume of the hydrogel slab. The support block is made of rigid or semi-rigid support material to restrain expansion of the hydrogel in all but one dimension, and the groove has one or more openings covered with a semipermeable membrane to allow contact between the patient's body fluid and the hydrogel. The scanning means may be any type of imaging devices such as an ultrasound scanner, a magnetic resonance imager (MRI), or a computerized tomographic scanner (CT) capable of resolving changes in the slab's dimensions.

Abstract: A biosensor (10) has a hydrogel (30) in a rigid and preferably biocompatible enclosure (20). The hydrogel (30) includes an immobilized analyte binding molecule (ABM) and an immobilized analyte. The immobilized analyte competitively binds with free analyte to the ABM, thus changing the number of crosslinks in the hydrogel (30), which changes hydrogel swelling tendency (and thus the osmotic pressure) in its confined space in proportion to the concentration of free analyte concentration. By measuring the change in hydrogel pressure with a pressure transducer (40), the biosensor (10) is able to accurately measure the concentration of the free analyte molecule without the problem of oxygen limitations and interference encountered by prior art biosensors. A battery (64) powered telemeter (60) operably engaged to the pressure transducer (40) sends a radio data signal to a receiver (66) containing an alarm system operably attached to a computer (62).

Abstract: An implantable biosensor for detecting an analyte in vivo in body fluids comprises an analyte-sensitive hydrogel filament chemically configured to vary its displacement volume according to changes in concentration of an analyte, such as glucose, in a patient's body fluid. A photometric displacement transducer placed inside the biosensor is configured to quantifiably detect changes in the displacement volume of the hydrogel filament, such as by detecting the light intensity on a photoreceptor arranged to receive light of varying intensity depending upon the displacement of the hydrogel filament. A battery powered telemeter operably engaged to the photometric displacement transducer sends a radio data signal representing glucose concentration level to a receiver containing an alarm system. The alarm system can automatically notify a person that the analyte level is outside desired predetermined parameters, and/or to automatically inject an agent to counteract the adverse analyte levels.

Abstract: A biosensor (10) has a hydrogel (30) in a rigid and preferably biocompatible enclosure (20). The hydrogel (30) includes an immobilized analyte binding molecule (ABM) and an immobilized analyte. The immobilized analyte competitively binds with free analyte to the ABM, thus changing the number of crosslinks in the hydrogel (30), which changes hydrogel swelling tendency (and thus the osmotic pressure) in its confined space in proportion to the concentration of free analyte concentration. By measuring the change in hydrogel pressure with a pressure transducer (40), the biosensor (10) is able to accurately measure the concentration of the free analyte molecule without the problem of oxygen limitations and interference encountered by prior art biosensors. A battery (64) powered telemeter (60) operably engaged to the pressure transducer (40) sends a radio data signal to a receiver (66) containing an alarm system operably attached to a computer (62).