Direct glucose detection in whole blood by colorimetric assay based on glucose oxidase-conjugated graphene oxide/MnO2 nanozymes

The Analyst ◽  
2019 ◽  
Vol 144 (9) ◽  
pp. 3038-3044 ◽  
Author(s):  
Po-Chun Lee ◽  
Nan-Si Li ◽  
Ying-Pei Hsu ◽  
Chen Peng ◽  
Hung-Wei Yang
Keyword(s):  
Graphene Oxide ◽  
Blood Sample ◽  
Glucose Concentration ◽  
Whole Blood ◽  
Direct Detection ◽  
Colorimetric Assay ◽  
Sample Pretreatment ◽  
Glucose Detection ◽  
Sensing Platforms ◽  
Dual Sensing

We have constructed dual sensing platforms based on the combination of a plasma separation pad and GOD-GO/MnO2 for direct detection of glucose concentration in whole blood by colorimetric assay without blood sample pretreatment and dilution.

A Simple and Rapid Method to Determine GPIIb/IIIa-Receptor Inhibitor Activity in Whole Blood

1999 ◽  
Vol 19 (03) ◽  
pp. 134-138
Author(s):  
Gitta Kühnel ◽  
A. C. Matzdorff
Keyword(s):  
Flow Cytometry ◽  
Platelet Count ◽  
Blood Sample ◽  
Platelet Activation ◽  
Whole Blood ◽  
Receptor Occupancy ◽  
Aggregate Formation ◽  
Inhibitor Activity ◽  
Receptor Inhibitor

SummaryWe studied the effect of GPIIb/IIIa-inhibitors on platelet activation with flow cytometry in vitro. Citrated whole blood was incubated with increasing concentrations of three different GPIIb/IIIa-inhibitors (c7E3, DMP728, XJ757), then thrombin or ADP were added and after 1 min the sample was fixed. Samples without c7E3 but with 0.1 U/ml thrombin had a decrease in platelet count. Samples with increasing concentrations of c7E3 had a lesser or no decrease in platelet count. The two other inhibitors (DMP 725, XJ757) gave similar results. GPIIb/IIIa-inhibitors prevent aggregate formation and more single platelets remain in the blood sample. The agonist-induced decrease in platelet count correlates closely with the concentration of the GPIIb/IIIa inhibitor and receptor occupancy. This correlation may be used as a simple measure for inhibitor activity in whole blood.

scholarly journals Fabrication methods for a gel-based separation-free device for whole blood glucose detection

MethodsX ◽  
2021 ◽  
Vol 8 ◽  
pp. 101236
Author(s):  
Han Zhang ◽  
Yongjian Yang ◽  
Jing Dai ◽  
Arum Han
Keyword(s):  
Blood Glucose ◽  
Whole Blood ◽  
Glucose Detection

scholarly journals Low-fouling CNT-PEG-hydrogel coated quartz crystal microbalance sensor for saliva glucose detection

RSC Advances ◽  
2021 ◽  
Vol 11 (37) ◽  
pp. 22556-22564
Author(s):  
Shiwen Wang ◽  
Guanjiang Liu ◽  
Bei Yang ◽  
Zifeng Zhang ◽  
Debo Hu ◽  
...  
Keyword(s):  
Quartz Crystal Microbalance ◽  
Binding Sites ◽  
Quartz Crystal ◽  
Direct Detection ◽  
Glucose Detection ◽  
Hydrogel Film ◽  
Glucose Binding ◽  
Quartz Crystal Microbalance Sensor

We successfully achieved the direct detection of saliva glucose by a CNT-PEG-hydrogel. The top CNT-PEG layer provides channels for transporting glucose molecules and filters macromolecular impurities and the bottom base PBA-hydrogel film provides the glucose binding sites.

scholarly journals A Novel Design Combining Isothermal Exponential Amplification and Gold-Nanoparticles Visualization for Rapid Detection of miRNAs

2018 ◽  
Vol 19 (11) ◽  
pp. 3374 ◽  
Author(s):  
Jiquan Jiang ◽  
Bin Zhang ◽  
Chi Zhang ◽  
Yifu Guan
Keyword(s):  
Early Phase ◽  
Color Change ◽  
Direct Detection ◽  
Colorimetric Assay ◽  
Disease Diagnosis ◽  
Dna Probes ◽  
Time Saving ◽  
Promising Alternative ◽  
Sandwich Hybridization ◽  
Wide Range

MicroRNAs (miRNAs) play important roles in a wide range of biological processes, and their aberrant expressions are associated with various diseases. The levels of miRNAs can be useful biomarkers for cellular events or disease diagnosis; thus, sensitive and selective detection of microRNAs is of great significance in understanding biological functions of miRNAs, early-phase diagnosis of cancers, and discovery of new targets for drugs. However, traditional approaches for the detection of miRNAs are usually laborious and time-consuming, with a low sensitivity. Here, we develop a simple, rapid, ultrasensitive colorimetric assay based on the combination of isothermal Exponential Amplification Reaction (EXPAR) and AuNP-labeled DNA probes for the detection of miRNAs (taking let-7a as a model analyte). In this assay, the presence of let-7a is converted to the reporter Y through EXPAR under isothermal conditions. The subsequent sandwich hybridization of the reporter Y with the AuNP-labeled DNA probes generates a red-to-purple color change. In other words, if the reporter Y is complementary to the AuNP-labeled DNA probes, the DNA-functionalized AuNPs will be aggregated, resulting in the change of solution color from red to purple/blue, while when the AuNP-labeled DNA probes are mismatched to the reporter Y, the solution remains red. This assay represents a simple, time-saving technique, and its results can be visually detected with the naked eye due to the colorimetric change. The method provides superior sensitivity, with a detection limit of 4.176 aM over a wide range from 1 nM to 1 aM under optimal conditions. The method also shows high selectivity for discriminating even single-nucleotide differences between let-7 miRNA family members. Notably, it is comparable to the most sensitive method reported to date, thus providing a promising alternative to standard approaches for the direct detection of let-7a miRNA. Importantly, through combination with specific templates, different miRNAs can be converted to the same reporter Y, which can hybridize with the same set of AuNP-labeled DNA probes to form sandwich hybrids. The color change of the solution can be observed in the presence of the target miRNA. This technique has potential as a routine method for assessing the levels of miRNAs, not only for let-7, but also for various miRNAs in the early phase of cancers. In addition, it can be a useful tool in biomedical research and clinical diagnosis, as well as diagnosis or surveillance programs in field conditions.

SAMPLE PRETREATMENT TO MINIMIZE INTERFERENCES FROM WHOLE BLOOD IN THE RADIOIMMUNOASSAY FOR CYCLOSPORINE

1986 ◽  
Vol 42 (4) ◽  
pp. 372-375 ◽  
Author(s):  
Gary L. Lensmeyer ◽  
Barry L. Fields ◽  
Ian H. Carlson ◽  
Diane deVos ◽  
Hans W. Sollinger
Keyword(s):  
Whole Blood ◽  
Sample Pretreatment

Enzyme-Free Plasmonic Biosensor for Direct Detection of Neurotransmitter Dopamine from Whole Blood

Nano Letters ◽  
2018 ◽  
Vol 19 (1) ◽  
pp. 449-454 ◽  
Author(s):  
Abraham Vázquez-Guardado ◽  
Swetha Barkam ◽  
Madison Peppler ◽  
Aritra Biswas ◽  
Wessley Dennis ◽  
...  
Keyword(s):  
Whole Blood ◽  
Direct Detection

scholarly journals Frequency of Lentz Bodies Inclusion in Whole Blood Erythrocytes and Expanded Buffy Coat Smears

2019 ◽  
Vol 47 (1) ◽  
Author(s):  
Monica Alejandra Camargo Castillo ◽  
Bruno Albuquerque De Almeida ◽  
Felipe Yuji Okano ◽  
Angelica Menin ◽  
Stella De Feira Valle
Keyword(s):  
Blood Sample ◽  
Whole Blood ◽  
Blood Cells ◽  
Inclusion Bodies ◽  
Blood Smear ◽  
Buffy Coat ◽  
Median Frequency ◽  
Canine Distemper ◽  
Blood Smears ◽  
Significant Difference

Background: Canine distemper has been classified as highly contagious for most of domestic and wild carnivores, and the infection can be fatal. Canine distemper inclusion bodies, also denominated Lenz inclusion bodies, are large aggregates of viral nucleocapsid particles that can be form in red blood cells (RBCs), white blood cells (WBCs) and epithelial cells in many tissues during the acute phase of infection. Their presence in blood is transient and rarely encountered in light microscopy but are pathognomonic when identified in blood smears. The objective of this study was to investigate the frequency of distemper inclusions in erythrocytes according to the fraction of the sample used for blood smears. Materials, Methods & Results: The study was conducted with routine blood sample provided by the Veterinary Laboratory of Clinical Analysis from the Veterinary Teaching Hospital of Universidade Federal do Rio Grande do Sul. The EDTA-K2 blood sample of a 40 days old male dog, mixed breed, no immunization records, presenting diarrhea, hyporexia, myoclonus and pustules in the abdomen, was selected. In a routine peripheral blood smear examination, several distemper inclusions were observed in the erythrocytes. From this sample, ten smears were performed using a whole blood (WB) and top erythrocyte fraction combined with buffy coat, denominated of expanded buffy coat (EBC). The EBC fraction was obtained after centrifugation of EDTA whole blood in microhematocrit tubes at 9600 x g for 5 min to obtained the packed cell volume (PCV) and buffy coat. After centrifugation, the blood cells are separated into three layers based on density: platelets (adjacent to supernatant), WBCs, and RBCs in the bottom. The PCV was measured and the microhematocrit tube was ruptured 2% below the interface between leukocytes and plasma, deposited into a plastic microtubes, homogenized and used for blood smear preparation. All smears were stained with Diff-Quick Stain. The frequency of observation of RBCs with distemper inclusions bodies was performed under optical microscopy, in the immersion objective (100x), accounting for complete fields up to a minimum of 1000 RBCs, and compared between WB and EBC. In comparison between blood smears obtained from WB and EBC, a highly significant difference (P = 0.0004) was observed in the frequency distribution of distemper inclusion. The median of frequency of RBCs with distemper inclusions in a WB smears was 12.68/1000 RBCs (10.1 - 16.1/1000 RBCs), with a coefficient of variation (CV) of 12%. Median of frequency of distemper inclusions from EBC smears was 54.23/1000 RBCs (45-77.9/1000 RBCs), CV of 18% were observed. The median frequency of inclusions found in EBC smears was 4.27 times higher than the WB smears. Discussion: Buffy coat smear providing a concentrated preparation of nucleated cells and this procedure is useful to looking for low-incidence infectious organisms or other hematologic alterations. The upper fraction of the RBC column, below the buffy coat, is composed of young RBCs. Selection of these portion, and their possible formed in the bone marrow viral replication phase, could justified the increase in the frequency of RBCs containing viral inclusions in EBC, which would also increase the sensitivity of the technique. EBC was homogenized previously to make the smears, certifying the adequate cell distribution in the slide surface without interfere with the frequency of distemper inclusion in RBCs observation. These results were confirmed with the coefficients of variation. In conclusion, distemper inclusions bodies in RBCs from EBC is a recommended diagnosis method in patients suspected of canine Distemper infection. The observation being more frequent in the EBC in comparison with WB, commonly used in veterinary hematology.

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