Non-invasive Optical Glucose Monitoring via Tissue Refractive Index

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Solution Overview

Problem

Current methods for monitoring blood glucose levels are invasive, inconvenient, costly, and lack accuracy and reliability, with non-invasive optical techniques facing challenges due to weak glucose absorption signals and interference from tissue components.

Innovation Solution

A non-invasive device that measures the refractive index of tissue by correlating the speed of electromagnetic radiation with glucose levels, using a device with an optical source and detector connected to an electronic processing unit to calculate and correlate the speed of radiation through tissue to glucose concentration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If non-invasive optical techniques (near-infrared spectroscopy, Raman spectroscopy) are used to measure blood glucose concentration, then the monitoring method becomes non-invasive and convenient, but the measurement accuracy deteriorates due to weak glucose absorption signals and interference from tissue components

Engineering Contradiction:

Improvenon-invasive monitoringVSAvoidglucose concentration accuracy

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The patent changes the measurement parameter from direct glucose absorption spectroscopy to refractive index measurement. By measuring the refractive index of tissue at specific wavelengths and correlating it to glucose concentration, the system achieves both non-invasive operation and improved measurement accuracy, resolving the contradiction between ease of operation and measurement precision

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces refractive index as an intermediary parameter between the optical measurement and glucose concentration. Instead of directly measuring glucose absorption, the system measures how glucose levels affect the refractive index of tissue, which then serves as a more reliable indicator for determining glucose concentration, thereby improving accuracy while maintaining non-invasive operation

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If traditional invasive blood sampling methods are used to monitor glucose levels, then measurement accuracy is maintained, but the monitoring process becomes painful, inconvenient, and requires frequent manual intervention

Engineering Contradiction:

Improveglucose concentration accuracyVSAvoidmonitoring convenience

Core Design Contradiction:

Measurement precisionVSEase of operation

Solution Approach 1:

The patent replaces the mechanical invasive sampling process with an optical measurement system. By using electromagnetic radiation to measure tissue refractive index, the system eliminates the need for needle punctures and manual blood sampling, achieving continuous automated monitoring while maintaining measurement accuracy through refractive index-correlated glucose determination

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Duration of action of stationary object

If semi-invasive glucose monitoring devices are implanted to provide continuous monitoring, then real-time glucose level monitoring is achieved, but the patient must undergo implantation surgery and the devices become inaccessible for maintenance

Engineering Contradiction:

Improvecontinuous monitoring capabilityVSAvoiddevice accessibility

Core Design Contradiction:

Duration of action of stationary objectVSEase of operation

Solution Approach 1:

The patent creates an external device that can be easily applied and removed, serving multiple functions including continuous monitoring, real-time data provision, and easy maintenance. The device achieves continuous monitoring capability through external optical measurement of tissue refractive index, eliminating the need for implantation while maintaining accessibility for adjustment and maintenance

Inventive Principle:

Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables continuous, accurate, and fast monitoring of glucose levels with high sensitivity and resolution, capable of detecting small fluctuations, and can be extended to monitor other blood constituents.

Implementation Method 1

the propagation speed of light through a medium v depends on its refractive index n, as v=c/n

Methodology Applied

Scientific EffectRefraction: Refraction

Implementation Method 2

measuring characteristics of the tissue that can be correlated to the refractive index of the tissue and to the speed at which electromagnetic radiation travels through the tissue

Methodology Applied

Scientific EffectElectromagnetic radiation propagation:

Data Source

PatentUS7486976B1Optical non-invasive blood monitoring system and method

Publication Date: 2009.02.03 BELOTSERKOVSKY EDWARD

AI summary

A simple noninvasive technique that is capable of very accurate and fast blood analyte, e.g., glucose, level monitoring is provided. Fluctuation in the levels of glucose and other analytes affect the refractive index of blood and extra cellular fluid in biological tissue. Given that the propagation speed of light through a medium depends on its refractive index, continuous monitoring of analyte levels in tissue is achieved by measuring characteristics of the tissue that can be correlated to the refractive index of the tissue. For instance, the frequency or number of optical pulse revelations that are transmitted through an individual's tissue of known thickness within a certain time period can be correlated to an individual's blood glucose level.