Implantable biosensor and methods of use thereof

An analyte sensing device comprising:

• an external control unit and an implantable sensor platform in wireless optical two-way operable communication, wherein the implantable sensor platform can pass though a 14 gauge or smaller bore needle,
• wherein the implantable sensor platform comprises sub-chip #1, sub-chip #2 and sub-chip#3 and a biocompatible coating surrounding at least a portion of the implantable sensor platform,
• wherein sub-chip #1 comprises:
• a photovoltaic device that powers the sub-chip #1, sub-chip #2 and sub-chip#3,
• a first optical receiver to receive instructions from a mode select unit located in the external control unit via an external unit optical transmitter, wherein the external unit optical transmitter is located in the external control unit, and
• a second optical receiver for providing information regarding light intensity received from light-emitting diodes located in the external control unit;
• wherein the first and second optical receivers operate at wavelengths such that the first and second optical receivers do not interfere with each other,
• a sensor platform optical transmitter configured to transmit an optical signal having a wavelength of in the range of 1.3 to 1.55 microns, relaying information selected from sensor output, calibration, potentiostat check, or solar power level check received from a driver located on subchip#2,
• one or more coatings providing wavelength selection, transmission or reflection functions,
• wherein sub-chip #2 comprises:
• a plurality of interfacing circuits selected from initialization circuits, sensor select circuits, and sensor calibration circuits,
• a potentiostat,
• a signal processing circuit,
• a logic circuit, a demultiplexer, a multiplexer, and the driver to enable transmission of feedback signals selected from a level of radiation intensity received by the photovoltaic device, a reference voltage of the potentiostat, or a sensor reading, and
• wherein the driver on subchip#2 transmits a plurality of pulses to the sensor platform optical transmitter located on subchip#1 and transmits using 1.3-1.55 micron optical wavelengths, and wherein the sensor platform optical transmitter does not interfere with the light emitting diodes and the external unit optical transmitter,
• wherein sub-chip #3 comprises a plurality of sensor elements operable for sensing of one or more analytes,
• and wherein the plurality of sensor elements has one or more working electrodes, a reference electrode and a counter electrode, wherein the one or more working electrodes, reference electrode and counter electrodes are in contact with the surface they are deposited on in a way that they do not delaminate when exposed to body fluids,
• wherein the plurality of sensor elements are in contact with the potentiostat and other circuits located on subchip #2,
• wherein sub-chip #1, sub-chip #2 and sub-chip#3 are electrically interconnected and integrated in a manner to operate in the presence of body fluids;
• wherein the external control unit comprises, in operable communication, an optical source comprising light-emitting diodes and laser diodes, wherein the optical source powers the photovoltaic device on sub-chip #1,
• a third optical receiver for receiving one or more optical pulses having a wavelength in the range of 1.3-1.55 micron from the sensor platform optical transmitter on subchip#1 of the implantable sensor platform,
• wherein the signal processing circuit converts a sensor element output signal to digital pulses,
• wherein the sensor platform optical transmitter converts the digital pulses to optical pulses,
• wherein the frequency of the optical pulses is determined by the sensor element output signal which is controlled by an analyte level in the body fluids,
• wherein the external unit optical transmitter transmits one or more optical pulses to the first optical receiver, wherein the one or more optical pulse relays instructions to sub-chip #2 for the switching, multiplexing, demultiplexing and logic circuits of sub-chip #2 to provide at least one function wherein the at least one function includes an initialization function, a power check function, a potentiostat circuit reconfiguration for analyte level measurement function, an implantable sensor selection function, and an implantable sensor calibration function,
• an integrated circuit for processing and displaying an electrical pulse, wherein the integrated circuit is in operable communication with an optical receiver,
• a microcontroller comprising a program code;
• programmable memory;
• a means to display the output and communicate with other devices;
• a means of interfacing with the optical source, an optical receiver located in the external control unit operating at 1.3 to 1.55 microns and an optical transmitter located in the external control unit operating at 800-1000 nanometers,
• a power supply to power the external control unit,
• one or more optical components providing wavelength selection, transmission, or reflection functions, and
• a miniaturized camera to align the implantable sensor platform with the optical components of the external control unit.

An implantable biosensor platform for sensing an analyte in a host, wherein the implantable biosensor is configured to operate with an external control unit, the implantable biosensor platform comprising:

• a photovoltaic device (PV), configured to receive power source light from the external control unit and convert the power source light into electricity used to power the implantable biosensor, wherein the power source light operates at a first wavelength;
• a plurality of electrodes, wherein at least one of the plurality of electrodes is configured to be exposed to the analyte to measure analyte levels;
• a first photodetector (PDm) configured to receive the power source light and generate input power level information responsive to the power source light;
• control circuitry configured to receive and compare the input power level information with a power reference level;
• a second photodetector (PDSS) configured to receive an optical control information signal from the external control unit, wherein the optical control information signal has a second wavelength;
• and
• processing circuitry configured to receive an electrical signal from at least one of the plurality of electrodes and convert the electrical signal into a digital signal which includes digital pulses whose frequency varies responsive to the electrical signal;
• and
• a transmitter (TXD) in signal communication with the processing circuitry and configured to optically transmit the digital signal to the external control unit, wherein the optical signal is transmitted via a third wavelength, wherein the first wavelength, second wavelength and third wavelength differ from each other.

An analyte sensing device, comprising:

• a sensor platform configured to be implantable within a living body having body fluids by passing through the bore of a needle, wherein the sensor platform is encapsulated in a biocompatible coating and comprises,
• a plurality of sensor elements each having a sensor surface, wherein when the sensor platform is located within the living body and the sensor surface is in contact with body fluid, the plurality of sensor elements generate a sensor output signal having a sensor output signal magnitude proportional to the concentration of the one or more analytes,
• a photovoltaic device (PV) configured to operate in response to electromagnetic energy from an external control unit optical power source and generate PV electrical output power for powering the sensor platform, wherein the sensor platform includes
• a sensor platform mode selector connected to,
• a multiplexer (MUX),
• a demultiplexer (DEMUX), and
• a logic circuit configured to perform,
• an initialization function,
• a power level check function,
• a potentiostat circuit reconfiguration function,
• a sensor selection function for measuring an analyte level, and
• a sensor calibration function, and
• a first optical receiver configured to operate at a 1st wavelength for detecting coded optical pulses produced by an external control unit optical transmitter,
• a potentiostat in operable communication with the plurality of sensor elements, wherein the potentiostat is configured to provide operating parameters to one or more of the plurality of sensor elements,
• a signal processing circuit configured to receive the sensor output signal and convert the sensor output signal into electrical digital pulses having a pulse frequency, wherein the pulse frequency is responsive to the sensor output signal magnitude such that changes in the pulse frequency are proportional to changes in the concentration of the one or more analytes,
• a sensor platform optical transmitter configured to operate at a 2nd wavelength to receive electrical digital pulses and convert the electrical digital pulses to optical digital pulses and transmit the optical digital pulses to an external control unit optical receiver, wherein the 2nd wavelength is not equal to the 1st wavelength,
• a 2nd optical receiver connected to the sensor platform mode selector and configured to receive electromagnetic energy from the external control unit optical power source and cause the sensor platform mode selector to send a signal to the external control unit via the sensor platform optical transmitter if the electromagnetic energy from the external control unit optical power source is above a threshold voltage.

An analyte sensing device for implantation into a living body via the bore of a needle, wherein the analyte sensing device is encapsulated in a biocompatible coating, the analyte sensing device comprising:

• at least one sensor element each having a sensor surface for sensing one or more analytes, wherein when the sensor platform is located within the living body and the sensor surface is in contact with body fluid, the at least one sensor element generates a sensor output signal having a sensor output signal magnitude proportional to the concentration of the one or more analytes,
• a photovoltaic device (PV) configured to operate responsive to electromagnetic energy from an external control unit optical power source and generate PV electrical output power for powering the analyte sensing device,
• a sensor platform mode selector,
• a first optical receiver configured to operate at a 1st wavelength for detecting coded optical pulses produced by an external control unit optical transmitter,
• a potentiostat in operable communication with the at least one sensor element, wherein the potentiostat is configured to provide operating parameters to the at least one sensor element,
• a signal processing circuit configured to receive the sensor output signal and convert the sensor output signal into electrical digital pulses having a pulse frequency, wherein the pulse frequency is responsive to the sensor output signal magnitude such that changes in the pulse frequency are proportional to changes in the concentration of the one or more analytes,
• a sensor platform optical transmitter configured to operate at a 2nd wavelength to receive electrical digital pulses and convert the electrical digital pulses to optical digital pulses and transmit the optical digital pulses to an external control unit optical receiver, wherein the 2nd wavelength is not equal to the 1st wavelength, and
• a 2nd optical receiver configured to operate responsive to the electromagnetic energy to cause the sensor platform mode selector to send a signal to the external control unit via the sensor platform optical transmitter if the electromagnetic energy is above a threshold voltage.