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Evaluation of dextrostix in blood sugar estimation

Buttery JE, de Witt GF, Ahmad UO

Med J Malaya, 1967 Jun;21(4):362-5.
PMID: 4230505
Matched MeSH terms: Blood Glucose/analysis*
An evaluation of the Beckman glucose analyser 2

Lim HH, Zaini-Rahman M

Med J Malaysia, 1979 Jun;33(4):317-20.
PMID: 522742
Matched MeSH terms: Blood Glucose/analysis*
The o-toluidine method for blood glucose determination

Buttery JE, de Witt GF, Omar Ahmad U

Med J Malaya, 1968 Sep;23(1):54-7.
PMID: 4237558
Matched MeSH terms: Blood Glucose/analysis*
Fulltext Study on different molecular weights of chitosan as an immobilization matrix for a glucose biosensor

Ang LF, Por LY, Yam MF

PLoS One, 2013;8(8):e70597.
PMID: 23940599 DOI: 10.1371/journal.pone.0070597

Two chitosan samples (medium molecular weight (MMCHI) and low molecular weight (LMCHI)) were investigated as an enzyme immobilization matrix for the fabrication of a glucose biosensor. Chitosan membranes prepared from acetic acid were flexible, transparent, smooth and quick-drying. The FTIR spectra showed the existence of intermolecular interactions between chitosan and glucose oxidase (GOD). Higher catalytic activities were observed on for GOD-MMCHI than GOD-LMCHI and for those crosslinked with glutaraldehyde than using the adsorption technique. Enzyme loading greater than 0.6 mg decreased the activity. Under optimum conditions (pH 6.0, 35°C and applied potential of 0.6 V) response times of 85 s and 65 s were observed for medium molecular weight chitosan glucose biosensor (GOD-MMCHI/PT) and low molecular weight chitosan glucose biosensor (GOD-LMCHI/PT), respectively. The apparent Michaelis-Menten constant ([Formula: see text]) was found to be 12.737 mM for GOD-MMCHI/PT and 17.692 mM for GOD-LMCHI/PT. This indicated that GOD-MMCHI/PT had greater affinity for the enzyme. Moreover, GOD-MMCHI/PT showed higher sensitivity (52.3666 nA/mM glucose) when compared with GOD-LMCHI/PT (9.8579 nA/mM glucose) at S/N>3. Better repeatability and reproducibility were achieved with GOD-MMCHI/PT than GOD-LMCHI/PT regarding glucose measurement. GOD-MMCHI/PT was found to give the highest enzymatic activity among the electrodes under investigation. The extent of interference encountered by GOD-MMCHI/PT and GOD-LMCHI/PT was not significantly different. Although the Nafion coated biosensor significantly reduced the signal due to the interferents under study, it also significantly reduced the response to glucose. The performance of the biosensors in the determination of glucose in rat serum was evaluated. Comparatively better accuracy and recovery results were obtained for GOD-MMCHI/PT. Hence, GOD-MMCHI/PT showed a better performance when compared with GOD-LMCHI/PT. In conclusion, chitosan membranes shave the potential to be a suitable matrix for the development of glucose biosensors.

Matched MeSH terms: Glucose/analysis*
Diluted glucose oxidase reagents adapted for use with Analox GM 7 Analyser for measuring plasma glucose

Loh SH

Ann. Clin. Biochem., 1989 Sep;26 ( Pt 5):453-4.
PMID: 2817758
Matched MeSH terms: Blood Glucose/analysis*
Fulltext Analysis and Testing of a Suitable Compatible Electrode's Material for Continuous Measurement of Glucose Concentration

Slaninova N, Fiedorova K, Selamat A, Danisova K, Kubicek J, Tkacz E, et al.

Sensors (Basel), 2020 Jun 30;20(13).
PMID: 32629993 DOI: 10.3390/s20133666

The subject of the submitted work is the proposal of electrodes for the continual measurement of the glucose concentration for the purpose of specifying further hemodynamic parameters. The proposal includes the design of the electronic measuring system, the construction of the electrodes themselves and the functionality of the entire system, verified experimentally using various electrode materials. The proposed circuit works on the basis of micro-ammeter measuring the size of the flowing electric current and the electrochemical measurement method is used for specifying the glucose concentration. The electrode system is comprised of two electrodes embedded in a silicon tube. The solution consists of the measurement with three types of materials, which are verified by using three solutions with a precisely given concentration of glucose in the form of a mixed solution and enzyme glucose oxidase. For the testing of the proposed circuit and the selection of a suitable material, the testing did not take place on measurements in whole blood. For the construction of the electrodes, the three most frequently used materials for the construction of electrodes used in clinical practice for sensing biopotentials, specifically the materials Ag/AgCl, Cu and Au, were used. The performed experiments showed that the material Ag/AgCl, which had the greatest sensitivity for the measurement even without the enzyme, was the most suitable material for the electrode. This conclusion is supported by the performed statistical analysis. On the basis of the testing, we can come to the conclusion that even if the Ag/AgCl electrode appears to be the most suitable, showing high stability, gold-plated electrodes showed stability throughout the measurement similarly to Ag/AgCl electrodes, but did not achieve the same qualities in sensitivity and readability of the measured results.

Matched MeSH terms: Glucose/analysis*
Novel alkaline-reduced cuprous oxide/graphene nanocomposites for non-enzymatic amperometric glucose sensor application

Yazid SNAM, Isa IM, Hashim N

Mater Sci Eng C Mater Biol Appl, 2016 Nov 01;68:465-473.
PMID: 27524043 DOI: 10.1016/j.msec.2016.06.006

This paper presents the fabrication of a highly sensitive and selective glucose sensor based on cuprous oxide/graphene nanocomposites-modified glassy carbon electrode (Cu2O/graphene/GCE). The Cu2O/graphene nanocomposites were synthesized based on a simple and straightforward chemical reduction process in alkaline aqueous solution using sodium carbonate as reductant. The size and shape of Cu2O nanoparticles on graphene sheets can be controlled by changing the amount of graphene oxide added during reaction. The electrochemical properties of Cu2O/graphene/GCE in 0.1M phosphate buffer solution were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. It was found that the pH, concentration of supporting electrolyte, and scan rate had very crucial effect on the sensitivity of prepared sensor towards glucose oxidation. At an applied potential of +0.50V, the Cu2O/graphene/GCE presented a high sensitivity of 1330.05μAmM(-1)cm(-2) and fast response (within 3s). The amperometric non-enzymatic glucose sensor developed had a linear relationship from 0.01mM to 3.0mM glucose and detection limit of 0.36μM. In the presence of ascorbic acid, uric acid, dopamine, chloride and citrate ion and other carbohydrates, the interferences were negligible. The proposed sensor was successfully applied for the determination of glucose concentration in real human blood samples.

Matched MeSH terms: Glucose/analysis*
In vitro glycation of dried serum

Ch'ng SL, Marinah TA

Clin Chim Acta, 1988 Apr 15;173(2):165-71.
PMID: 3378356 DOI: 10.1016/0009-8981(88)90254-9

In vitro glycation of sera dried on water-resistant medium (Parafilm) and on paper were studied by measuring the change of glucose level, fructosamine:total protein ratio, glycated protein concentration and alteration of electrophoretic mobility of sera before and after drying. The results suggested the instability of glucose in dried sera was due to in vitro glycation which was influenced by surface properties of media on which the sera were deposited. A new method for rapid effective in vitro glycation of sera was also proposed.

Matched MeSH terms: Blood Glucose/analysis*
A new approach to detecting sugar syrup addition to honey: Stable isotope analysis of hexamethylenetetramine synthesised from honey monosaccharides (fructose and glucose)

Li A, Abrahim A, Islam M, Mejías E, Hafizati Abdul Halim N, Frew R, et al.

Food Chem, 2024 Feb 15;434:137451.
PMID: 37748289 DOI: 10.1016/j.foodchem.2023.137451

One of the most common types of adulteration of honey involves the addition of invert sugar syrups. A new method was developed to measure the stable isotope ratios of carbon and carbon-bound non-exchangeable (CBNE) hydrogen from specific molecular positions in fructose and glucose in honey. This was achieved through periodate oxidation of the sugars to produce formaldehyde, followed by reaction with ammonia to form hexamethylenetetramine (HMT). The preparation was simplified, optimized, and validated by isotopic analysis of replicate syntheses of HMT from fructose, glucose, sugar syrup and a representative authentic honey sample. The optimized method had a repeatability standard deviation from 1.5‰ to 3.0‰ and from 0.1‰ to 0.4‰ for δ2H and δ13C, respectively. This methodology has advantages over alternative isotopic methods, for measuring CBNE hydrogen isotope ratios in sugars, in terms of time, sensitivity and operability and offers a complementary method to differentiate authentic honey from invert sugar syrups.

Matched MeSH terms: Glucose/analysis
Minimizing tissue-material interaction in microsensor for subcutaneous glucose monitoring

Ahmad F, Christenson A, Bainbridge M, Yusof AP, Ab Ghani S

Biosens Bioelectron, 2007 Mar 15;22(8):1625-32.
PMID: 16934449

A new implantable electrocatalytic glucose sensor for subcutaneous glucose monitoring has been fabricated by immobilizing glucose oxidase on a chemically modified carbon fiber. The sensor was inserted subcutaneously on a male spraguely rat without any incision after dipping the microsensor in the rat's serum for 3 days. The so called "stained" microsensor, operated in the amperometric mode with an applied potential of +0.23 V versus Ag|AgCl, was able to directly measure the glucose concentration upon infusion of glucose. The results obtained were encouraging, with the response time was less than 2s and the apparent Michaelis-Menten value at 5.1+/-0.5mM. The "stained" microsensor shows good stability and reproducibility with constant response spanned over 25 days. Most common interferences in glucose analysis were minimized by the outerlayer Nafion. Hematology examinations showed minimal material-tissue interaction. Use of such mechanical devices will allow a more refined understanding towards glucose control in diabetic patients as the implanted microsensor was not effected by biocompatibility failures.

Matched MeSH terms: Blood Glucose/analysis; Glucose/analysis*
Synthesis and characterization of Co3O4 ultra-nanosheets and Co3O4 ultra-nanosheet-Ni(OH)2 as non-enzymatic electrochemical sensors for glucose detection

Mahmoudian MR, Basirun WJ, Woi PM, Sookhakian M, Yousefi R, Ghadimi H, et al.

Mater Sci Eng C Mater Biol Appl, 2016 Feb;59:500-508.
PMID: 26652401 DOI: 10.1016/j.msec.2015.10.055

The present study examines the synthesis of Co3O4 ultra-nanosheets (Co3O4 UNSs) and Co3O4 ultra-nanosheet-Ni(OH)2 (Co3O4 UNS-Ni(OH)2) via solvothermal process and their application as non-enzymatic electrochemical sensors for glucose detection. X-ray diffraction and transmission electron microscopy results confirmed the Co3O4 UNS deposition on Ni(OH)2 surface. The presence of Co3O4 UNSs on Ni (OH) 2 surface improved the sensitivity of glucose detection, from the increase of glucose oxidation peak current at the Co3O4 UNS-Ni(OH)2/glassy carbon electrode (current density: 2000μA·cm(-2)), compared to the Co3O4 UNSs. These results confirmed that Ni(OH)2 on glassy carbon electrode is a sensitive material for glucose detection, moreover the Co3O4 UNSs can increase the interaction and detection of glucose due to their high surface area. The estimated limit of detection (S/N=3) and limit of quantification (S/N=10) of the linear segment (5-40μM) are 1.08μM and 3.60μM respectively. The reproducibility experiments confirmed the feasibility of Co3O4 UNS-Ni(OH)2 for the quantitative detection of certain concentration ranges of glucose.

Matched MeSH terms: Glucose/analysis*
The electrochemical behaviour of ferrocene in a photocurable poly(methyl methacrylate-co-2-hydroxylethyl methacrylate) film for a glucose biosensor

Bean LS, Heng LY, Yamin BM, Ahmad M

Bioelectrochemistry, 2005 Feb;65(2):157-62.
PMID: 15713567

A single-step fabrication of a glucose biosensor with simultaneous immobilization of both ferrocene mediator and glucose oxidase in a photocurable methacrylic film consisting of poly(methyl methacrylate-co-2-hydroxylethyl methacrylate) was reported. The entrapped ferrocene showed reversible redox behaviour in the photocured film and no significant leaching of both entrapped ferrocene and enzyme glucose oxidase was observed because of the low water absorption properties of the co-polymer films. From electrochemical studies, ferrocene entrapped in the co-polymer film demonstrated slow diffusion properties. A linear glucose response range of 2-11 mM was obtained at low applied potential of +0.25 V. The glucose biosensor fabricated by this photocuring method yielded sensor reproducibility and repeatability with relative standard deviation of <10% and long-term stability of up to 14 days. The main advantage of the use of photocurable procedure is that biosensor membrane fabrication can be performed in a single step without any lengthy chemical immobilization of enzyme.

Matched MeSH terms: Glucose/analysis*
Fulltext Glucose: a reevaluation of its intraoperative use in paediatric surgery

Lim SK, Loh SP

Med J Malaysia, 1997 Mar;52(1):64-9.
PMID: 10968055

Blood glucose concentration was measured in 100 children immediately before and during surgery. These children were randomly assigned to receive either lactated Ringer's (LR) solution or 5% dextrose in lactated Ringer's (5%D/LR) intraoperatively as maintenance and replacement fluids. Blood samples were taken immediately after induction of anaesthesia and at 1/2, 1, 1.5, 2 and subsequent hours. Blood glucose concentration was assayed by a reflectance meter. None of the patients was noted to be hypoglycaemic pre- and intraoperatively. Intraoperative blood glucose concentration increased significantly (p < 0.05) from preoperative levels for both groups of children but the increase in those that received 5%D/LR was significantly greater (p < 0.05) than those who received LR. The number of children who were hyperglycaemic during surgery was also greater in those who received 5% dextrose in lactated Ringer's as their intraoperative fluid. These data suggest that lactated Ringer's alone is a safe and appropriate fluid for intraoperative fluid therapy in children.

Matched MeSH terms: Blood Glucose/analysis*
Fulltext The effect of Ramadan fasting on fasting serum glucose in healthy adults

Larijani B, Zahedi F, Sanjari M, Amini MR, Jalili RB, Adibi H, et al.

Med J Malaysia, 2003 Dec;58(5):678-80.
PMID: 15190653

The effect of Ramadan fasting on fasting serum glucose (FPG) is still a matter of controversy. One hundred and fifteen healthy volunteers fasted for > or = 25 days during Ramadan. Blood samples were taken 1 week before Ramadan and on the 14th and 28th day of Ramadan. Serum glucose was determined by the glucose oxidase method. FPG decreased from 88.4 + 9.0 mg/dl to 62.9 +/- 7.7 mg/dl (p < 0.001). Men and women both experienced a significant drop in FPG. Calorie intake decreased in all groups (p < 0.001) and was positively correlated with decreasing FPG. FPG decreases with Ramadan fasting and has no serious adverse effect on fasting adults.

Matched MeSH terms: Blood Glucose/analysis*
Influence of dietary cholesterol on the total cholesterol and free to ester cholesterol ration of blood and tissues of normal and alloxan diabetic rats

Bhattathiry EP

Med J Malaya, 1966 Dec;21(2):128-30.
PMID: 4227382
Matched MeSH terms: Blood Glucose/analysis*
Fulltext Implications for Drug Characterization in Glucose Tolerance Tests Without Insulin: Simulation Study of Power and Predictions Using Model-Based Analysis

Sheikh Ghadzi SM, Karlsson MO, Kjellsson MC

CPT Pharmacometrics Syst Pharmacol, 2017 10;6(10):686-694.
PMID: 28575547 DOI: 10.1002/psp4.12214

In antihyperglycemic drug development, drug effects are usually characterized using glucose provocations. Analyzing provocation data using pharmacometrics has shown powerful, enabling small studies. In preclinical drug development, high power is attractive due to the experiment sizes; however, insulin is not always available, which potentially impacts power and predictive performance. This simulation study was performed to investigate the implications of performing model-based drug characterization without insulin. The integrated glucose-insulin model was used to simulate and re-estimated oral glucose tolerance tests using a crossover design of placebo and study compound. Drug effects were implemented on seven different mechanisms of action (MOA); one by one or in two-drug combinations. This study showed that exclusion of insulin may severely reduce the power to distinguish the correct from competing drug effect, and to detect a primary or secondary drug effect, however, it did not affect the predictive performance of the model.

Matched MeSH terms: Blood Glucose/analysis*
Fulltext Virtual Screening, Synthesis, and Biological Evaluation of Some Carbohydrazide Derivatives as Potential DPP-IV Inhibitors

Jadhav PB, Jadhav SB, Zehravi M, Mubarak MS, Islam F, Jeandet P, et al.

Molecules, 2022 Dec 24;28(1).
PMID: 36615348 DOI: 10.3390/molecules28010149

Dipeptidyl peptidase-4 (DPP-IV) inhibitors are known as safe and well-tolerated antidiabetic medicine. Therefore, the aim of the present work was to synthesize some carbohydrazide derivatives (1a-5d) as DPP-IV inhibitors. In addition, this work involves simulations using molecular docking, ADMET analysis, and Lipinski and Veber's guidelines. Wet-lab synthesis was used to make derivatives that met all requirements, and then FTIR, NMR, and mass spectrometry were used to confirm the structures and perform biological assays. In this context, in vitro enzymatic and in vivo antidiabetic activity evaluations were carried out. None of the molecules had broken the majority of the drug-likeness rules. Furthermore, these molecules were put through additional screening using molecular docking. In molecular docking experiments (PDB ID: 2P8S), many molecules displayed more potent interactions than native ligands, exhibiting more hydrogen bonds, especially those with chloro- or fluoro substitutions. Our findings indicated that compounds 5b and 4c have IC50 values of 28.13 and 34.94 µM, respectively, under in vitro enzymatic assays. On the 21st day of administration to animals, compound 5b exhibited a significant reduction in serum blood glucose level (157.33 ± 5.75 mg/dL) compared with the diabetic control (Sitagliptin), which showed 280.00 ± 13.29 mg/dL. The antihyperglycemic activity showed that the synthesized compounds have good hypoglycemic potential in fasting blood glucose in the type 2 diabetes animal model (T2DM). Taken all together, our findings indicate that the synthesized compounds exhibit excellent hypoglycemic potential and could be used as leads in developing novel antidiabetic agents.

Matched MeSH terms: Blood Glucose/analysis
Associations of the glycaemic index and the glycaemic load with risk of type 2 diabetes in 127 594 people from 20 countries (PURE): a prospective cohort study

Miller V, Jenkins DA, Dehghan M, Srichaikul K, Rangarajan S, Mente A, et al.

Lancet Diabetes Endocrinol, 2024 May;12(5):330-338.
PMID: 38588684 DOI: 10.1016/S2213-8587(24)00069-X

BACKGROUND: The association between the glycaemic index and the glycaemic load with type 2 diabetes incidence is controversial. We aimed to evaluate this association in an international cohort with diverse glycaemic index and glycaemic load diets.
METHODS: The PURE study is a prospective cohort study of 127 594 adults aged 35-70 years from 20 high-income, middle-income, and low-income countries. Diet was assessed at baseline using country-specific validated food frequency questionnaires. The glycaemic index and the glycaemic load were estimated on the basis of the intake of seven categories of carbohydrate-containing foods. Participants were categorised into quintiles of glycaemic index and glycaemic load. The primary outcome was incident type 2 diabetes. Multivariable Cox Frailty models with random intercepts for study centre were used to calculate hazard ratios (HRs).
FINDINGS: During a median follow-up of 11·8 years (IQR 9·0-13·0), 7326 (5·7%) incident cases of type 2 diabetes occurred. In multivariable adjusted analyses, a diet with a higher glycaemic index was significantly associated with a higher risk of diabetes (quintile 5 vs quintile 1; HR 1·15 [95% CI 1·03-1·29]). Participants in the highest quintile of the glycaemic load had a higher risk of incident type 2 diabetes compared with those in the lowest quintile (HR 1·21, 95% CI 1·06-1·37). The glycaemic index was more strongly associated with diabetes among individuals with a higher BMI (quintile 5 vs quintile 1; HR 1·23 [95% CI 1·08-1·41]) than those with a lower BMI (quintile 5 vs quintile 1; 1·10 [0·87-1·39]; p interaction=0·030).
INTERPRETATION: Diets with a high glycaemic index and a high glycaemic load were associated with a higher risk of incident type 2 diabetes in a multinational cohort spanning five continents. Our findings suggest that consuming low glycaemic index and low glycaemic load diets might prevent the development of type 2 diabetes.
FUNDING: Full funding sources are listed at the end of the Article.

Matched MeSH terms: Blood Glucose/analysis
Hydrothermal and wet disk milling pretreatment for high conversion of biosugars from oil palm mesocarp fiber

Zakaria MR, Norrrahim MN, Hirata S, Hassan MA

Bioresour Technol, 2015 Apr;181:263-9.
PMID: 25659104 DOI: 10.1016/j.biortech.2015.01.072

Eco-friendly pretreatment methods for lignocellulosic biomass are being developed as alternatives to chemical based methods. Superheated steam (SHS), hot compressed water (HCW) and wet disk milling (WDM) were used individually and with combination to partially remove hemicellulose and alter the lignin composition of recalcitrant structure of oil palm mesocarp fiber (OPMF). The efficiency of the pretreatment methods was evaluated based on the chemical compositions altered, SEM analysis, power consumption and degree of enzymatic digestibility. Hemicellulose removal (94.8%) was more pronounced under HCW compared to SHS, due to maximal contact of water and production of acetic acid which enhanced further degradation of hemicellulose. Subsequent treatment with WDM resulted in defibrillation of OPMF and expansion of the specific surface area thus increasing the conversion of cellulose to glucose. The highest glucose yield was 98.1% (g/g-substrate) when pretreated with HCW (200 °C, 20 min) and WDM which only consumed 9.6 MJ/kg of OPMF.

Matched MeSH terms: Glucose/analysis
The influence of deep frying using various vegetable oils on acrylamide formation in sweet potato (Ipomoea batatas L. Lam) chips

Lim PK, Jinap S, Sanny M, Tan CP, Khatib A

J Food Sci, 2014 Jan;79(1):T115-21.
PMID: 24344977 DOI: 10.1111/1750-3841.12250

The objective of this study was to evaluate the precursors of acrylamide formation in sweet potato (SP) (Ipomoea batatas L. Lam) chips and to determine the effect of different types of vegetable oils (VOs), that is, palm olein, coconut oil, canola oil, and soya bean oil, on acrylamide formation. The reducing sugars and amino acids in the SP slices were analyzed, and the acrylamide concentrations of SP chips were measured. SP chips that were fried in a lower degree of unsaturation oils contained a lower acrylamide concentration (1443 μg/kg), whereas those fried with higher degree of unsaturated oils contained a higher acrylamide concentration (2019 μg/kg). SP roots were found to contain acrylamide precursors, that is, 4.17 mg/g glucose and 5.05 mg/g fructose, and 1.63 mg/g free asparagine. The type of VO and condition used for frying, significantly influenced acrylamide formation. This study clearly indicates that the contribution of lipids in the formation of acrylamide should not be neglected.

Matched MeSH terms: Glucose/analysis

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