spectroscopy on rat skin in relation 2 glucose sensing

Passing a selected band of radiation and extracting the glucose concentration from the resulting spectrum is the main idea behind the spectrscopic approaches. Tissue chemical components and the distribution of chemical constituents in a skin matix contribute the output spectrum for analysis. Apart from this, temperatures and pressures of the tissue also have impact on optical properties of the non-invasive spectrum.
Fixed interface of fibre optics with skin gives unscattered output spectra for further predictions.


References:
1)Natalia V. Alexeeva, B.S., and Mark A. Arnold, Ph.D.,Near-Infrared Microspectroscopic Analysis of Rat Skin Tissue Heterogeneity in Relation to Noninvasive Glucose Sensing,J Diabetes Sci Technol Vol 3, Issue 2, March 2009.

Near Infrared Technology

The usage of light spectrum of different wavelengths to detect the blood sugar values is known as near infrared spectroscopy.
There is also a research going on the wireless glucometers like glucowatch called SymphonytCGM where the biosensor of type glucose oxidase send the data wirelessly to handheld device, but this has some problem like The longevity of the sensor, the accuracy of the device, the transdermal blood glucose variation (in terms of the time lag) and longitudinal adverse outcomes should further be explored.”

Wireless tech and telehealth systems are the most promising outcomes of the future non-invasive blood glucose meters.Here’s how: individual sensor results from the NIR non-invasive meter would be sent wirelessly to a mainframe system and within seconds the results from the NIR technology would be delivered via SMS mobile messaging to the patient. In this way, the technology could be downloaded by physicians and educators for assessing patient care and record-keeping, making it as competitive as the current CGM system without inserting a subcutaneous sensor.

References:
An article from the link http://asweetlife.org/elizabeth/blogs/products/scientists-getting-closer-to-the-end-of-painful-blood-glucose-testing/8789/

Impedance based Monitoring

various parameters that influence the measurements are the influence of environmental/body temperature changes, changes in the blood perfusion of the skin under test or blood flux, underlying tissue volume and changes in the contacts of sensor / skin due to movements. the relation ship between the change in glucose concentration and the impedance of skin underlying tissue has the positive correlation [1].

In order to avoid the interferences, the following sensors are used:capacitive fringing field electrodes, inter-digitated electrodes for impedance and galvanic response of skin respectively and the capacitive sensors for penetration depths of electromagnetic field in to the skin besides an optical sensor for blood flux measurement, finally the moments of the study objects are taken care by 3 axis accelerometer. the whole set up is shown in below fig.Results shown the decrease in conductance to the increase in glucose level, where the inverse of conductance is taken for impedance calculation [1].

Reference:
[1]M.S. Talary1, F. Dewarrat1, D. Huber1, L. Falco-Jonasson1 and A. Caduff1 Non-Invasive Impedance based Continuous Glucose Monitoring System, ICEBI 2007, IFMBE Proceedings Vol. 17.

Instantanous Differential Near Infrared Spectrscopy

Temporial difference of Ir spectra from the finger tip has the arterial pulse which is the area of interest in the present high speed spectrophoyometer. Influence of basal components like resting blood, bones, skin and muscles are removed from pulsatile blood component [1].
There are some of the other methods that exploit the effect the glucose called erythrocyte scattering, new photoacoustic phenomenon, optical coherence tomography, thermo-optical studies on human skin, Raman spectroscopy studies, fluorescence measurements, and use of photonic crystals [2].

References:
[1]Proceedings of the 29th Annual International Conference of the IEEE EMBS Cité Internationale, Lyon, France August 23-26,2007 called "A New Non-invasive Method for Measuring Blood Glucose Using Instantaneous Differential Near Infrared Spectrophotometry" by
Y. Yamakoshi, M. Ogawa, T. Yamakoshi, M. Satoh, M. Nogawa S. Tanaka, T. Tamura, P. Rolfe,
& K. Yamakoshi.
[2]O. S. Khalil, “Non-invasive Glucose Measurement Technologies: AnUpdate from 1999 to the Dawn of the New Millennium,’’ Diabetes Technol. Ther., vol. 6, pp. 660-697, 2004

Optical Glucose measurement

There are quite a few methods that use Infrared Spectroscopy principle but with different mathematical calibrations like Dynamic Concentration Correction algorithm in Raman spectrscopy [1], Clarke error grid analysis[2] etc

References:
[1]Press release on August 9, 2010 by Massachusetts Institute of technology
[2]An article from Applied Spectroscopy, Vol. 60, Issue 12, pp. 1423-1431 (2006) called "Noninvasive Near-Infrared Blood Glucose Monitoring Using a Calibration Model Built by a Numerical Simulation Method" by Katsuhiko Maruo, Tomohiro Oota, Mitsuhiro Tsurugi, Takehiro Nakagawa, Hidenobu Arimoto, Mineji Hayakawa, Mamoru Tamura, Yukihiro Ozaki, and Yukio Yamada

Electro-Enzymatic Sensor

The other way of measureing the glucose is by using the electrodes made of glodfabricated on glass slides, one electrode with enyzme for glucose oxidase and other is for reference. currernt is generated from this setup to estimate the glucose level [1].

References:
[1]An IEEE article called "Electro-Enzymatic Sensor for Non-Invasive Glucose Measurement" by
Jasbir N. Patel1, Bonnie Gray1, Bozena Kaminska1 and Byron Gates2 from Simon Fraser University, Burnaby, BC, CANADA.

Infrered Spectroscopy

IR Spectroscopy is based on the vibrations of atoms in a molecule, and the idea behind the IR spectrum is by passing the infrared radiation in to a target sample and obtaining the absorption spectra at a particular energy. these changes in the interaction of energy with matter is because of the freedom of rotational and vibrational physics in an atom[1].

Infrared spectroscopy has wide range of applications in blood serum. the proteins, lipids,carbohydrates etc of red blood cells have a sense of absorption spectra in Infrared region due to the nature of the bond between carbon-oxygen, carbon-nitrogen and nitrogen-oxygen etc. so many medical applications like heart surgeries, coronary treatments use this instrument for anaysis [1].

References:
[1] A book called "Biological Applications of Infrared Spectrscopy" by Barbara Staurt, University of Technology, Sydney, Australia.

Bloodless Diabetes Monitoring

A new approach of making the glucose sensor is by using the microwave circuit that generates the electromagnetic waves. when ever a persons finger is placed on the chip, change in the electrical properties of the thumb is observed. these changes were used in the measurements of glucose level [1].
Fig(1). Spiral shaped glucose sensor
the energy change on the thumb places over the above shown sensor is because of blood, muscle, fat, skin, and glucose. so, when the spectrum is filtered in broad frequency range estimation of required biological constraint level is possible

References:
[1]An article from technology review called " Bloodless Diabetes Monitoring-A new noninvasive tool uses electromagnetic waves to measure glucose levels" by Jennifer Chu.

Glucose painless monitors

In order to avoid the negative affects of the blood glucose like neuropathies, blindness, coma, and sequela etc, one must have continous monitor on their sugar levels. the present reliable method of noticing body's glucose is by finger pricking and using glucose oxidase to get the value, but this painfull approach is discouraging most of the individuals to keep their record update. so, these consequencies lead to the studies on non-invasive techniques for continous easy monitoring of ones glucose levels(1).

Easy Measurement of more glucose values and wide spread usage of its applications than invasive methods appealed Near Infrered Spectroscopy(NIRS)[2].

Human body generates radiation in the range of Mid Infrared region contains spectral information of tissue analytes, but depends on ones tissue composition and analyte concentration[3].



References:
[1]"Glucose biosensors as models for the development of advanced protein-based biosensors" by
Maria Staiano,a Paolo Bazzicalupo,b Mose’ Rossia and Sabato D’Auria*a

[2] An Article called "Transcutaneous Glucose Measurement Using Near-Infrared Spectroscopy During poglycemia" from diabetes care by ILAN GABRIELY, MD, ROBERT WOZNIAK, MD, MICHÈLE MEVORACH, MD, JONATHAN KAPLAN, MD, YIGAL AHARON, MD, and HARRY SHAMOON, MD.

[3]An original artical from emerging treatments and technology called "A Novel Noninvasive Blood Glucose Monitor" by CARL D. MALCHOFF, MD, PHD, KAMAL SHOUKRI, MD, JULIAN I. LANDAU, MS, JANUSZ M. BUCHERT, PHD.

Glucose Measures Overview.

Complex syndrome in human body is its irregular usage of glucose present called as Diabetes Mellitus. Regular monitoring and therapy is the only solution for this disease, There are many ways of measuring the blood sugar level among which optical technique is one of the major fields of interest for fast and painless measurements(1).

Present paper gives an overview demonstration of blood less glucose measurement using Near Infrared Spectroscopy, one can also find the biological and physical aspects concerning the measurement.

References:

[1] Overview of Non-Invasive Fluid Glucose Measurement Using Optical Techniques to Maintain Glucose Control in Diabetes Mellitus

R. W. Waynant, Ph.D.* and V. M. Chenault, Ph.D., MT(ASCP)**

15 ECTS POINTS MASTER’S PROJECT IN EMBEDDED VIDEO PROCESSING SYSTEM

Bloodless Glucose Measurement

Introduction

This project is about making a biosensor for bloodless glucose measurement. People with diabetes measure the blood glucose level several times each day using a lancet to get a drop of blood on a test strip.

Figure 1. Example of standard blood glucose measurement

Non-invasive techniques can be based on IR- or NIR measurements, often in combination with several measurements.

Objectives

The objective of this project is to use the infrared spectroscopy equipment at the university to demonstrate the functionality of blood glucose measurements.

To achieve this, the student must also demonstrate understanding both of the biological aspects and the physical aspects of the measurement.

Tasks

1. Literature study of different techniques for bloodless glucose measurements

2. Inventory of different available systems that are presented on the webb. Comparison on their relative assumed prestanda.

3. Building of a demonstrator using available equipment at the university optical lab.

4. Written report.

Supervisor

Börje Norlin Borje.Norlin@miun.se

Henrik Andersson Henrik.Andersson@miun.se

mailto:oppo1002@student.miun.se