Reverse Iontophoresis - Faculty Server Contact

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Eric
› VeraLight Scout DS
› LighTouch Glucose Monitor
› OrSense NBM-200G
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Barbara
› GlucoScope
› GlucoView

Tim
› GlucoWatch
› EZ Scan
› Symphony tCGM
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Study of the interaction of matter and
light
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Light is focused on some area of the body
Light is absorbed and reflected in different
ways
Subcategories include near-infrared, midinfrared, and photoacoustic spectroscopy.
Detect the presence of glucose by
observing the reflectance of light against
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Scout DS
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Consists of a light source, an optical detector, and
spectrometer, all located on an arm-rest.
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Uses spectroscopy to measure advanced glycation end
products (AGE)
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Glycation occurs when a protein or lipid is bonded
with glucose.
Hyperglycemia from diabetes results in higher
cellular glucose levels.
This leads to increased glycation, and increased
levels of AGE formation.
Product is only useful for predicting the development
of Type 2 diabetes.
May eventually replace the current invasive diabetes
screening methods.
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LighTouch Glucose Monitor
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12 issued patents, more pending.
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Projects a specific wavelength of light onto
fingertip and detects the wavelength of
reflected light.
Designed for daily testing and accuracy equal
to finger-stick method.
Clinical trials began in 1999 with Joslin
Diabetes Center, Syracuse, New York.
Monitor has been continually redesigned
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Improvements have been made in
speed, accuracy, cost, and form-factor.
Currently in the process of getting FTA
approval.
Plans on releasing home version six to
nine months after approval.
Potential to replace traditional method.
Plans to use their technology for other
blood analyte measurement devices.
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NBM-200G Glucose Monitor
Specific version of their NBM-200MP which measures
hemoglobin, oximetry, and pulse rate.
Based on proprietary Occlusion spectroscopy
technology.
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Sensor wraps around finger, applying pressure.
The change in blood dynamics is used in allowing a
strong optical response.
51 patents worldwide, more than 20 pending.
Developed the concept of measuring analytes
through occlusion of blood flow, a unique finger
sensor, and algorithms to facilitate the
OrSense NBM-200MP
OrSense NBM-200G
Image Source: http://www.orsense.com
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NBM-200G currently
undergoing clinical
trials.
Tested on over 450
subjects over a 24-hour
period
“At this stage the NBM200G glucose monitor
is utilized for
investigation and
market awareness
purpose only”
Image Source: http://www.orsense.com/?id=815

Eric
› VeraLight Scout DS
› LighTouch Glucose Monitor
› OrSense NBM-200G

Barbara
› GlucoScope
› GlucoView

Tim
› GlucoWatch
› EZ Scan
› Symphony tCGM
Produced by Visual Pathways Inc
 Received federal grant in 2003 under the
U.S Department of the Army Medical
Research Acquistion Activity
 Received a patent December 2004
 Measures the glucose levels in the fluid
of the anterior chamber of the eye
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A vision care diagnostic company
 Headquarters in Prescott, Arizona
 Developed a prototype in 2003
 GlucoScope Monitor uses infrared light
to rapidly measure glucose levels in the
eye
 The handheld device looks like a small
pair of binoculars
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https://www.diabetesnet.com/diabetes-technology/meters-monitors/future-metersmonitors/visual-pathways
The cornea
and a lens form
the anterior
chamber
The anterior is
also comprised
of the iris and
the aqueous
humor
Glucose concentration in the
bloodstream is directly correlated to the
concentration in the aqueous humor
 Variation in the glucose concentration
will cause variations in its index of
refraction
 The refractive index can be measured
by interferometry
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Two beams are directed into the eye
and caused to interfere
 The interference produces a fringe
pattern (bright and dark lines)
 The pattern is analyzed and the index of
refraction of the eye is determined
 The glucose concentrations is then
determined
 The glucose level in the blood can be
determined from this information
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Handheld
 Portable
 Digital readout
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Still in the research and development
phase
 Not commercially available
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Produced by Sentek Group Inc
 Licensed from the University of Pittsburg
 Disposable contact lens which changes
color according to glucose levels in tears
 Uses a Crystalline Colloidal Array
Technology
 A red shift indicates hyperglycemia
 A purple shift indicates hypoglycemia
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When the CCA is polymerized within a
hydrogel PCCA , the PCCA optically
reports volume changes experienced by
the hydrogel
 This is because the observed diffraction
wavelength is directly related to the
spacing between lattice planes
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The CCAs are brightly colored because
they diffract visible light due to Bragg’s
diffraction
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nλ = 2dsinθ
where,
n is an integer
λ = wavelength of the incident wave
d is the spacing
Bragg diffraction depends on the refractive
index of the system and the spacing
between the diffracting planes
It is non-invasive (no finger pricks)
 It requires no instrumentation( to collect
fluids or to analyze results)
 Provides easily measurable, quantitative
results
 It is low-cost
 Continuous monitoring
 Helpful for caretakers of children and
elderly
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Necessary to wear contact lenses (most
diabetics have vision problems)
 Does not collect data for future analysis
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
Eric
› VeraLight Scout DS
› LighTouch Glucose Monitor
› OrSense NBM-200G

Barbara
› GlucoScope
› GlucoView

Tim
› GlucoWatch
› EZ Scan
› Symphony tCGM
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Technique for extracting subdermal
molecules
› Apply DC current to the skin
› Current attracts charged molecules
› Force of the flow also draws neutral
molecules
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Glucose and lactate are among the
molecules which can be extracted
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First commercially available non-invasive
glucose measurement technique
› Continuous monitoring
› Requires blood test for calibration
› Suffers inaccuracy in detecting
hypoglycemia
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Discontinued by Animas Corporation in
2007
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Tool for blood sugar testing
› Two minute test
› Utilizes five sensors
 In regions rich with sweat glands
 2 hands, 2 feet, 1 forehead
Requires no calibration
 Still in developmental stages
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Transdermal Continuous
glucose monitoring
› Real time
› Biosensor broadcasts
wirelessly to a monitoring tool
› No calibration
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Uses a proprietary skin
permeation device Prelude
› Improves effectiveness of
reverse iontophoresis
Image source: www.echotx.com
Improves permeability of skin
for reverse iontophoresis
 Tool removes the outmost
layer of epidermis (stratum
corneum)
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› Uses feedback control
algorithm to prevent damage
› .01mm in thickness comprised
of dead skin
Image source:
www.echotx.com
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Spectroscopy and Reverse Iontophoresis
› Viable solutions for Non-Invasive Glucose
Measurement
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Symphony tCGM is one of the most
viable candidates
› Barbara maintains that the GlucoView will
ultimately win
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