Transcript Organic chemistry

Optical Glucose Sensor
Yonathan Essaw
Outline
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Explain Diabetes
Treatment
Problem
Optical Glucose Sensors
Fluorescence (luminescence)
Boronic Acid
Reaction Mechanism
Conclusion and future research
What is Diabetes?
• Diabetes is a chronic disease that affects
the body's ability to produce or respond
to insulin, the hormone that allows
glucose to enter the body's cells and be
stored or used for energy.
• Many diabetics require insulin injections,
and all must carefully monitor and
manage their blood glucose levels.
http://currents.ucsc.edu/03-04/03-15/glucose.html
Type of Diabities
Type 1 diabetes
• Juvenile diabetes or
insulin-dependent
diabetes
• first diagnosed in
children, teenagers, or
young adults.
• the beta cells of the
pancreas no longer
make insulin because
the body's immune
system has attacked and
destroyed them
•http://diabetes.niddk.nih.gov/dm/pubs/type1and2/what.htm
Type 2 diabetes
• Adult-onset diabetes or
noninsulin-dependent
diabetes
• usually begins with
insulin resistance, a
condition in which fat,
muscle, and liver cells
do not use insulin
properly
• Being overweight and
inactive increases the
chances of developing
type 2 diabetes.
Treatment
Type 1 diabetes
• Treatment for type 1
diabetes includes taking
insulin shots or using an
insulin pump, making
wise food choices, being
physically active, taking
aspirin daily (for some),
and controlling blood
pressure and
cholesterol.
http://diabetes.niddk.nih.gov/dm/pubs/type1and2/what.htm
Type 2 diabetes
• Treatment for type 2
diabetes includes
using diabetes
medicines, making
wise food choices,
being physically
active, taking aspirin
daily, and controlling
blood pressure and
cholesterol.
Problem
• For millions of diabetics, this means drawing
blood several times a day, usually from finger
pricks. But glucose levels can fluctuate widely
throughout the day, making it difficult to know
when to do the blood tests for optimal control
of glucose levels.
• A device, such as the optical glucose sensor,
that can provide continuous monitoring of
blood sugar would sharply reduce the risk of
long term complications, which includes
blindness, hearth attack, and kidney failures.
http://www.medicalnewstoday.com/index.php?newsid=6673
Optical Glucose Sensor
• A Glucose sensor is designed to
automatically measure interstitial sugar
every few minutes, without any user
intervention.
http://www.mendosa.com/third_generation.htm
Main Idea
• The Idea is that as the intensity of
fluorescence varies, information is
transmitted through radio waves by an
implanted device equipped with both light
source and a photodetector.
• Then the waves would be received by
another device worn outside the body,
and information regarding the individual’s
glucose level would trigger an alarm.
Optical Glucose Sensor
• Glucose sensor uses a
hydrogel—a polymer similar
to contact lenses, that is
permeable to glucose.
• A Fluorescent chemical
compound is contained within
a hydogel polymer for
stabilization inside the body.
• The Hydrogel has multiple
functionalities as a enzyme
reservoir and a skin sensor,
and maintaining osmotic
gradient for glucose
extraction form the skin.
http://www.sontra.com/pdfs/[email protected]
Optical Glucose Sensor
• The hydrogel polymer can
be placed under the skin
or in a major blood vessel.
Along with th fluorescent
dye, the sensor contains a
molecule, called a
“quencher.”
• Quencher acts as a kind of
switch for the dye. In the
absence of glucose, the
quencher binds to the dye
and prevents fluorescence.
When glucose is present,
the light shines brighter.
http://www.osa-opn.org/view_file.cfm?doc=%24)%3C3%2FJ0%20%20%0A&id=%24*%2C%23'J%20%20%20%0A
Fluorescence
luminescence
• (luminescence) A molecule absorbs a high-energy
photon, and re-emits it as a lower-energy (longerwavelength) photon. The energy difference between
the absorbed and emitted photons ends up as
molecular vibrations (heat).
http://www.absoluteastronomy.com/encyclopedia/f/fl/fluorescence.htm
Fluorescence
& Sensors
• Fluorescence is a very sensitive
technique, it is possible to detect single
molecules. Fluorescent sensors for
saccharides have been developed based
on the interaction between a boronic acid
and a diol.
• Fluorescent sensors based on the Lewis
acid-base interaction between a boronic
acid and fluoride ions have been devised.
http://www.bath.ac.uk/chemistry/james/
Color changes
• The picture shows
the visible color
change observed on
the addition of Dglucose to a solution
of a boronic acid azo
dye molecule
http://www.bath.ac.uk/chemistry/james/
Boronic acid
• Boronic acid is a chemical compound
that binds to sugar. “We decided to go
with a light source (fluorescence),
because light is very sensitive. There are
instruments that can measure one single
photon,” Singaram a researcher at UCSC
said.
Boronic Acid
• Laboratories around the country have
been experimenting on Boronic acidbased, optical glucose sensor using
fluorescence as a detection method.
• The use of the boronic acids as chelator
groups for monosacharides has attracted
increasing attention for the development
of alternative approach in glucose
monitoring .
http://www.osa-opn.org/view_file.cfm?doc=%24)%3C3%2FJ0%20%20%0A&id=%24*%2C%23'J%20%20%20%0A
Typically Used Systems
9-[[N-Methyl-N-(o-boronobenzyl)amino]methyl]anthracene
9,10-Bis[ [N-methyl-N-(o- boronobenzyl)amino]methyl] anthracene
file:///C:/Documents%20and%20Settings/libstu.SJCC_STU.001/Local%20Settings/Temporary%20Internet%20Files/Content.IE5/8HST656D/275,7,Slide 7
Basic Mechanism
Reaction Mechanism
file:///C:/Documents%20and%20Settings/libstu.SJCC_STU.001/Local%20Settings/Temporary%20Internet%20Files/Content.IE5/8HST656D/275,7,Slide 7
Reaction Mechanism
Mechanism
file:///C:/Documents%20and%20Settings/libstu.SJCC_STU.001/Local%20Settings/Temporary%20Internet%20Files/Content.IE5/8HST656D/275,7,Slide 7
9,10-Bis[ [N-methyl-N-(o- boronobenzyl)amino]methyl]
anthracene
Conclusion
• It is extremely important for humans to find ways of
treatment for diabetes.
• An Instrument such as the Optical Glucose Sensors
will make great impact on the fight against diabetes.
• Boronic acids based fluorescence sugar sensors can
be designed selectively for glucose.
Further Research
• Current research is directed towards the
synthesis of thin film polymers that
contain the sensing components for
longer term stability.
http://www.chemistry.ucsc.edu/~singaram/research%20files/Optical%20Glucose.htm
Bibliography
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http://edcp.org/factsheets/aids.htmlhttp://chemistry.about.com/library/weekly/aa031703a.htm
http://www.chem.sc.edu/faculty/wang/overview.html
http://pubs.acs.org/subscribe/journals/mdd/v05/i05/html/05news3.html
http://www.chemistry.ucsc.edu/~singaram/research%20files/Optical%20Glucose.htm
http://cfs.umbi.umd.edu/cfs/reprints/New%20Color%20Chemosensors.pdf#search='boronic%2
0acid%20sensors%20Diabetes‘
http://diabetes.niddk.nih.gov/dm/pubs/type1and2/what.htm
http://www.betterhumans.com/Errors/index.aspx?aspxerrorpath=/Glowing_Sensor_May_Allow_
Artificial_Pancreas.Article.2004-03-17-3.aspx
http://cfs.umbi.umd.edu/cfs/reprints/New%20Color%20Chemosensors.pdf
http://www.bath.ac.uk/chemistry/james/
file:///C:/Documents%20and%20Settings/libstu.SJCC_STU.001/Local%20Settings/Temporary
%20Internet%20Files/Content.IE5/8HST656D/269,23,Slide 23
Yehaaaaaa……am done
Thank You