Determination of light source modules on blood glucose biomimetics using the reflectance method

Abstract Because we recently observed two patients with severe diabetic hyperglycemia and spuriously elevated electronically determined hematocrit and mean corpuscular volume (MCV), we investigated the effect of hyperglycemia on two popular automated hematology systems, the Coulter S and Ortho ELT-8. Marked hyperglycemia (blood glucose 800-- 2000 mg/dl) caused consistent overestimation of the electronically determined MCV compared to that derived from a simultaneous spun microhematocrit. The resultant overestimation and underestimation, respectively, of the derived values for hematocrit and mean corpuscular hemoglobin concentration may be clinically misleading. The mechanism of MCV elevation in hyperglycemia appears to be swelling of hyperosmolar glucose “loaded” erythrocytes when diluted into “isotonic” counting medium. This effect is readily circumvented by determination of a spun microhematocrit.

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THE MICRO-DETERMINATION OF BLOOD GLUCOSE

Australian Journal of Experimental Biology and Medical Science ◽

10.1038/icb.1963.21 ◽

1963 ◽

Vol 41 (3) ◽

pp. 211-220 ◽

Cited By ~ 5

Author(s):

D Watson ◽

MEK Stevenson

Keyword(s):

Blood Glucose

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Performance of the Ascensia ENTRUST glucose meter for determination of blood glucose concentration in rats

Veterinary Clinical Pathology ◽

10.1111/j.1939-165x.2009.00169.x ◽

2009 ◽

Vol 38 (4) ◽

pp. 493-500

Author(s):

S. Vijayakumar ◽

Nancy E. Everds ◽

P. Kalaiselvan ◽

R.K. Shakthidevan ◽

Yogesh Kumar V. Murkunde ◽

...

Keyword(s):

Blood Glucose ◽

Glucose Concentration ◽

Blood Glucose Concentration ◽

Glucose Meter

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Antecubital Vein Cannula Position Impacts Assessment of Forearm Glucose Uptake During an Oral Glucose Challenge in Healthy Volunteers

Experimental and Clinical Endocrinology & Diabetes ◽

10.1055/a-1275-4038 ◽

2020 ◽

Author(s):

Cécile Bétry ◽

Aline V. Nixon ◽

Paul L. Greenhaff ◽

Elizabeth J. Simpson

Keyword(s):

Skeletal Muscle ◽

Blood Glucose ◽

Glucose Uptake ◽

Venous Blood ◽

Whole Body ◽

Oral Glucose ◽

Antecubital Vein ◽

Glucose Challenge ◽

The Impact

Abstract Introduction Skeletal muscle is a major site for whole-body glucose disposal, and determination of skeletal muscle glucose uptake is an important metabolic measurement, particularly in research focussed on interventions that impact muscle insulin sensitivity. Calculating arterial-venous difference in blood glucose can be used as an indirect measure for assessing glucose uptake. However, the possibility of multiple tissues contributing to the composition of venous blood, and the differential in glucose uptake kinetics between tissue types, suggests that sampling from different vein sites could influence the estimation of glucose uptake. This study aimed to determine the impact of venous cannula position on calculated forearm glucose uptake following an oral glucose challenge in resting and post-exercise states. Materials and Methods In 9 young, lean, males, the impact of sampling blood from two antecubital vein positions; the perforating vein (‘perforating’ visit) and, at the bifurcation of superficial and perforating veins (‘bifurcation’ visit), was assessed. Brachial artery blood flow and arterialised-venous and venous blood glucose concentrations were measured in 3 physiological states; resting-fasted, resting-fed, and fed following intermittent forearm muscle contraction (fed-exercise). Results Following glucose ingestion, forearm glucose uptake area under the curve was greater for the ‘perforating’ than for the ‘bifurcation’ visit in the resting-fed (5.92±1.56 vs. 3.69±1.35 mmol/60 min, P<0.01) and fed-exercise (17.38±7.73 vs. 11.40±7.31 mmol/75 min, P<0.05) states. Discussion Antecubital vein cannula position impacts calculated postprandial forearm glucose uptake. These findings have implications for longitudinal intervention studies where serial determination of forearm glucose uptake is required.

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Οπτικοί βιοαισθητήρες για την ανίχνευση βιομορίων χωρίς τη χρήση ιχνηθετών

10.12681/eadd/40034 ◽

2015 ◽

Author(s):

Αιμιλία Ψαρούλη

Keyword(s):

Light Source ◽

Silicon Substrate ◽

Serum Samples ◽

Fully Integrated ◽

Monolithically Integrated ◽

Immunochemical Determination ◽

Wide Range ◽

Myocardial Infraction ◽

Biological Recognition

Recent developments in the fields of bioanalytical chemistry and microelectronics have resulted in a growing trend of transferring the classical analytical methods from the laboratory bench to the field through the development of portable devices or microsystems based on biosensors. Biosensors are self-contained integrated devices capable to provide analytical information using biological recognition molecules in direct spatial contact with a transducer. Biosensors using antibodies or antigens as biological recognition elements are termed as immunosensors and they are based on the same principle as the classical solid-phase immunoassays.The aim of this thesis was to develop and evaluate an optical immunosensor based on Mach-Zehnder Interferometry and integrated on silicon substrate for the immunochemical determination of clinical analytes. The optical sensor developed is fabricated entirely by mainstream silicon technology by the Optical Biosensors group of the Institute of Nanoscience and Nanotechnology of NCSR “Demokritos” and combines arrays of ten sensors in a single silicon chip. Each sensor consists of an integrated on silicon light source that emits a broad spectrum in visible-near ultraviolet range and it is coupled to an integrated silicon nitride waveguide which has been patterned into Mach-Zehnder interferometer. The signal is recorded either through a photodetector monolithically integrated onto the same silicon chip (fully integrated configuration) or through an external spectrometer (semi-integrated configuration). In the fully integrated configuration, the signal recorded is the total photocurrent across the whole spectral range, while in semi-integrated configuration the whole transmission spectrum is continuously recorded and is mathematically transformed (Fourier Transform) to phase shift. As in the classical Mach-Zehnder interferometers, the waveguide in the proposed sensor is split into two arms, the sensing one which is appropriately modified with recognition biomolecule and the reference arm that is covered by a protective layer. The specific binding of the analyte with the immobilized onto the surface recognition biomolecule causes an effective refractive index change at the surface of the sensing arm thus affecting the phase of the waveguided light with respect to the reference arm. Thus, when the two arms converge again, an interference spectrum is generated that is altered during bioreaction providing the ability of monitoring in real-time and without using labels. The main difference of the sensor developed with respect to classical Mach-Zehnder interferometers is that the light source is monolithically integrated on the same silicon substrate with the waveguides and the waveguided light is not monochromatic, but broad spectrum.At first in this study, the method for chemical activation of biofunctionalization of chips was optimized. It was found that the highest signals were obtained when chips where activated by (3-aminopropyl)triethoxysilane and deposition of biomolecules solutions using a microarray spotter. Then, a comparison of the two sensor configurations, i.e. the fully and the semi-integrated configuration was performed using a model binding assay namely the streptavidin-biotin reaction. Semi-integrated configuration provided higher detection sensitivities mainly due to lower between-sensor signal variation in the same chip and between different chips. Thus, this configuration was selected for further evaluation with respect to the determination of analytes of clinical interest and especially of immunochemical determination of C-reactive protein in human serum samples. CRP is a marker of inflammation widely used in everyday clinical practice for diagnosis and therapy monitoring of inflammatory situations. Nevertheless, CRP has been also proposed as a prognostic marker of myocardial infraction and three risk levels have been established; low risk for serum CRP concentrations < 1 μg/mL; medium risk for concentrations in the range 1-3 μg/mL; and high risk for concentrations >3 μg/mL. In the frame of the present thesis, enzyme immunoassays for the determination of CRP in microtitration plates both competitive and non-competitive were developed in order to select the most appropriate reagents and define the immunoassay conditions. Then both assay format were transferred and evaluated on the sensor. It was found that the non-competitive format offered higher responses and ability for regeneration of immobilized onto the sensor antibody against CRP and was therefore selected for the final sensor evaluation. The assay developed following the competitive format was sensitive and accurate as was demonstrated through recovery and dilution linearity experiments, and provided for analysis of samples with a wide range of CRP concentrations since it was immune to the presence of serum. In addition, the CRP values determined with the immunosensor developed in serum samples from unknown donors were in good agreement with those determined for the same samples by commercially available kits and instruments showing the reliability of the determinations performed with the immunosensor developed and its potential for analysis of clinical samples.

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Determination of X-ray flux using silicon pin diodes

Journal of Synchrotron Radiation ◽

10.1107/s0909049508040429 ◽

2009 ◽

Vol 16 (2) ◽

pp. 143-151 ◽

Cited By ~ 55

Author(s):

Robin L. Owen ◽

James M. Holton ◽

Clemens Schulze-Briese ◽

Elspeth F. Garman

Keyword(s):

Light Source ◽

Energy Deposition ◽

Photon Flux ◽

Macromolecular Crystallography ◽

Pin Diodes ◽

Web Based ◽

X Ray ◽

Swiss Light Source ◽

Flux Incident

Accurate measurement of photon flux from an X-ray source, a parameter required to calculate the dose absorbed by the sample, is not yet routinely available at macromolecular crystallography beamlines. The development of a model for determining the photon flux incident on pin diodes is described here, and has been tested on the macromolecular crystallography beamlines at both the Swiss Light Source, Villigen, Switzerland, and the Advanced Light Source, Berkeley, USA, at energies between 4 and 18 keV. These experiments have shown that a simple model based on energy deposition in silicon is sufficient for determining the flux incident on high-quality silicon pin diodes. The derivation and validation of this model is presented, and a web-based tool for the use of the macromolecular crystallography and wider synchrotron community is introduced.

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DETERMINATION OF GLUCOSE IN FISH BLOOD: A MODIFICATION OF THE FOLIN–MALMROS MICROPROCEDURE

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o58-121 ◽

1958 ◽

Vol 36 (11) ◽

pp. 1121-1124 ◽

Cited By ~ 8

Author(s):

Leonard R. Murrell ◽

Paul F. Nace

Keyword(s):

Blood Glucose ◽

Prussian Blue ◽

Tungstic Acid ◽

Sodium Lauryl Sulphate ◽

Blood Proteins ◽

Colorimetric Measurement ◽

Efficient Separation ◽

Fish Blood

A modification of the Folin–Malmros micromethod is described for the determination of fish blood glucose. A more efficient separation of blood proteins is obtained by precipitating 0.1 ml blood in 10.0 ml tungstic acid. This is followed by hot alkaline reduction of ferricyanide, and colorimetric measurement of a Prussian blue – sodium lauryl sulphate suspension. The method, which eliminates certain difficulties found in other procedures, has been successfully applied in more than a thousand analyses of blood from two species of fish (Opsanus and Ictalurus) having glucose concentrations between 15 and 250 mg per cent.

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Study on the determination of reference closed orbit of the storage ring in Pohang Light Source

Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366) ◽

10.1109/pac.1999.795556 ◽

2003 ◽

Author(s):

A.H. Maeng ◽

K.W. Kim ◽

T.Y. Lee ◽

S.C. Lee ◽

J.S. Bak

Keyword(s):

Light Source ◽

Storage Ring ◽

Closed Orbit ◽

Pohang Light Source

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Non-Invasive Determination of Blood Glucose Levels by Optical Waveguide

Iranian journal of diabetes and obesity ◽

10.18502/ijdo.v13i4.8001 ◽

2021 ◽

Author(s):

Mohsen Askarbioki ◽

Mojtaba Mortazavi ◽

Abdolhamid Amooee ◽

Saeid Kargar ◽

Mohammad Afkhami-Ardekani ◽

...

Keyword(s):

Blood Glucose ◽

Optical Waveguide ◽

Interstitial Fluid ◽

Evanescent Waves ◽

The Body ◽

Statistical Population ◽

Glucose Levels ◽

Non Invasive ◽

Blood Glucose Levels

Objective: Today, there are various non-invasive techniques available for the determination of blood glucose levels. In this study, the level of blood glucose was determined by developing a new device using near-infrared (NIR) wavelength, glass optical waveguide, and the phenomenon of evanescent waves. Materials and Methods: The body's interstitial fluid has made possible the development of new technology to measure the blood glucose. As a result of contacting the fingertip with the body of the borehole rod, where electromagnetic waves are reflected inside, evanescent waves penetrate from the borehole into the skin and are absorbed by the interstitial fluid. The electromagnetic wave rate absorption at the end of the borehole rod is investigated using a detection photodetector, and its relationship to the people's actual blood glucose level. Following precise optimization and design of the glucose monitoring device, a statistical population of 100 participants with a maximum blood glucose concentration of 200 mg/dL was chosen. Before measurements, participants put their index finger for 30 seconds on the device. Results: According to this experimental study, the values measured by the innovative device with Clark grid analysis were clinically acceptable in scales A and B. The Adjusted Coefficient of Determination of the data was estimated to be 0.9064. Conclusion: For future investigations, researchers are recommended to work with a larger statistical population and use error reduction trends to improve the accuracy and expand the range of measurements.

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