Diagnosis and genotyping of Plasmodium falciparum by a DNA biosensor based on quartz crystal microbalance (QCM)

2011 ◽  
Vol 49 (8) ◽  
Author(s):  
Tiparat Potipitak ◽  
Warunee Ngrenngarmlert ◽  
Chamras Promptmas ◽  
Sirinart Chomean ◽  
Wanida Ittarat
Keyword(s):  
Quartz Crystal Microbalance ◽  
Malaria Infection ◽  
Quartz Crystal ◽  
High Sensitivity ◽  
Cost Effective ◽  
Dna Biosensor ◽  
Dual Function ◽  
Label Free ◽  
Free Dna ◽  
Nanogram Level

AbstractMalaria infection withA label-free DNA biosensor based on quartz crystal microbalance (QCM) to diagnose and genotypeThe newly developed QCM was tested for its diagnosis ability using both malaria laboratory strains and clinical isolates. The biosensor was sensitive at the sub-nanogram level, specific for onlyThe dual function QCM was successfully developed with high sensitivity and specificity, and was cost-effective, stable and field adaptable.

An Enhanced Electrochemical Biosensing on Gold Electrodes with the Ferri/Ferrocyanide Redox Couple

The Analyst ◽  
2021 ◽  
Author(s):  
Seowon Lee ◽  
Won Jae Kim ◽  
Minsub Chung
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Electrochemical Impedance ◽  
Redox Couple ◽  
Label Free ◽  
Dna Sensing ◽  
Electrochemical Biosensing ◽  
Free Dna

Detection of specific DNA is important in many fields. Label-free DNA sensing performed by electrochemical impedance spectroscopy (EIS) or by a quartz crystal microbalance (QCM) is widely employed for this...

scholarly journals Quantitative Assessment of Periodontal Bacteria Using a Cell-Based Immunoassay with Functionalized Quartz Crystal Microbalance

Chemosensors ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 159
Author(s):  
Satit Rodphukdeekul ◽  
Miyuki Tabata ◽  
Chindanai Ratanaporncharoen ◽  
Yasuo Takeuchi ◽  
Pakpum Somboon ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Quartz Crystal Microbalance ◽  
Quantitative Assessment ◽  
Quartz Crystal ◽  
Dynamic Range ◽  
Gold Surface ◽  
Enzyme Linked Immunosorbent Assay ◽  
Inflammatory Disorder ◽  
Label Free ◽  
Periodontal Bacteria

Periodontal disease is an inflammatory disorder that is triggered by bacterial plaque and causes the destruction of the tooth-supporting tissues leading to tooth loss. Several bacteria species, including Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, are considered to be associated with severe periodontal conditions. In this study, we demonstrated a quartz crystal microbalance (QCM) immunoassay for quantitative assessment of the periodontal bacteria, A. actinomycetemcomitans. An immunosensor was constructed using a self-assembled monolayer of 11-mercaptoundecanoic acid (11-MUA) on the gold surface of a QCM chip. The 11-MUA layer was evaluated using a cyclic voltammetry technique to determine its mass and packing density. Next, a monoclonal antibody was covalently linked to 11-MUA using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide to act as the biorecognition element. The specificity of the monoclonal antibody was confirmed by an enzyme-linked immunosorbent assay. A calibration curve, for the relationship between the frequency shifts and number of bacteria, was used to calculate the number of A. actinomycetemcomitans bacteria in a test sample. Based on a regression equation, the lower detection limit was 800 cells, with a dynamic range up to 2.32 × 106 cells. Thus, the QCM biosensor in this study provides a sensitive and label-free method for quantitative analysis of periodontal bacteria. The method can be used in various biosensing assays for practical application and routine detection of periodontitis pathogens.

Label-free DNA detection based on oligonucleotide-stabilized silver nanoclusters and exonuclease III-catalyzed target recycling amplification

2014 ◽  
Vol 6 (15) ◽  
pp. 6082-6087 ◽  
Author(s):  
Hui Ma ◽  
Wei Wei ◽  
Qian Lu ◽  
Zhixin Zhou ◽  
Henan Li ◽  
...  
Keyword(s):  
High Sensitivity ◽  
Silver Nanoclusters ◽  
Label Free ◽  
Exonuclease Iii ◽  
Target Recycling ◽  
Free Dna ◽  
Sensitivity And Selectivity ◽  
Exo Iii ◽  
Ag Ncs ◽  
Recycling Amplification

A label-free DNA biosensor with high sensitivity and selectivity is constructed by using DNA–Ag NCs and Exo III-catalyzed target recycling amplification.

Cardiac troponin T detection using polymers coated quartz crystal microbalance as a cost-effective immunosensor

2010 ◽  
Vol 55 (5) ◽  
pp. 279-284 ◽  
Author(s):  
Krongkamol Wong-ek ◽  
Orawon Chailapakul ◽  
Noppadon Nuntawong ◽  
Kata Jaruwongrungsee ◽  
Adisorn Tuantranont
Keyword(s):  
Quartz Crystal Microbalance ◽  
Cardiac Troponin ◽  
Quartz Crystal ◽  
Troponin T ◽  
Cost Effective ◽  
Cardiac Troponin T

scholarly journals Rapid and Simultaneous Quantification of 4 Urinary Proteins by Piezoelectric Quartz Crystal Microbalance Immunosensor Array

2006 ◽  
Vol 52 (12) ◽  
pp. 2273-2280 ◽  
Author(s):  
Yang Luo ◽  
Ming Chen ◽  
Qianjun Wen ◽  
Meng Zhao ◽  
Bo Zhang ◽  
...  
Keyword(s):  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Clinical Chemistry ◽  
Label Free ◽  
Urinary Proteins ◽  
Quartz Crystals ◽  
Piezoelectric Quartz ◽  
Piezoelectric Immunosensor ◽  
Highly Sensitive ◽  
Piezoelectric Quartz Crystal

Abstract Background: Urinary proteins are predictive and prognostic markers for diabetes nephropathy. Conventional methods for the quantification of urinary proteins, however, are time-consuming, and most require radioactive labeling. We designed a label-free piezoelectric quartz crystal microbalance (QCM) immunosensor array to simultaneously quantify 4 urinary proteins. Methods: We constructed a 2 × 5 model piezoelectric immunosensor array fabricated with disposable quartz crystals for quantification of microalbumin, α1-microglobulin, β2-microglobulin, and IgG in urine. We made calibration curves after immobilization of antibodies at an optimal concentration and then evaluated the performance characteristics of the immunosensor with a series of tests. In addition, we measured 124 urine samples with both QCM immunosensor array and immunonephelometry to assess the correlation between the 2 methods. Results: With the QCM immunosensor array, we were able to quantify 4 urinary proteins within 15 min. This method had an analytical interval of 0.01–60 mg/L. The intraassay and interassay imprecisions (CVs) were <10%, and the relative recovery rates were 90.3%–109.1%. Nonspecificity of the immunosensor was insignificant (frequency shifts <20 Hz). ROC analyses indicated sensitivities were ≥95.8% and, specificities were ≥76.3%. Bland–Altman difference plots showed the immunosensor array to be highly comparable to immunonephelometry. Conclusions: The QCM system we designed has the advantages of being rapid, label free, and highly sensitive and thus can be a useful supplement to commercial assay methods in clinical chemistry.

Label-free DNA biosensor based on a peptide nucleic acid-functionalized microstructured optical fiber-Bragg grating

2013 ◽  
Vol 18 (5) ◽  
pp. 057004 ◽  
Author(s):  
Alessandro Candiani ◽  
Alessandro Bertucci ◽  
Sara Giannetti ◽  
Maria Konstantaki ◽  
Alex Manicardi ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Optical Fiber ◽  
Fiber Bragg Grating ◽  
Peptide Nucleic Acid ◽  
Dna Biosensor ◽  
Bragg Grating ◽  
Label Free ◽  
Microstructured Optical Fiber ◽  
Free Dna ◽  
Optical Fiber Bragg Grating

Longitudinal monitoring of cell-free DNA to predict for transarterial chemo-embolization failure in hepatocellular carcinoma.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e14544-e14544
Author(s):  
Joanne Evans ◽  
Caroline Ward ◽  
Madhava Pai ◽  
Rohini Sharma
Keyword(s):  
Hepatocellular Carcinoma ◽  
Early Stage ◽  
High Sensitivity ◽  
Cost Effective ◽  
Standard Of Care ◽  
Intermediate Stage ◽  
Cell Free Dna ◽  
Early Stage Disease ◽  
Free Dna ◽  
Synthetic Function

e14544 Background: Transarterial chemo-embolization (TACE) is the standard of care for patients with intermediate stage hepatocellular carcinoma (HCC) with adequate synthetic function, and as bridging treatment in early stage disease. Survival outcomes are heterogeneous, and improved biomarkers are needed for detection of early relapse. Current practice relies on monitoring of alpha-foetoprotein (AFP) and serial imaging. Circulating cell-free DNA (cfDNA) is a compelling emergent biomarker. Here, we describe the first study of cfDNA as prognostic biomarker in HCC following TACE. Methods: 34 patients treated with TACE (2012-2018) who had full demographic information and longitudinal stored plasma available were identified. Samples were retrieved and cfDNA extracted using the QIAamp Circulating Nucleic Acid Kit. cfDNA yields were quantified by high-sensitivity Qubit analysis. Results: 74% of patients were male, 66% had Childs Pugh A disease, and 56% of patients secreted AFP ( > 10ng/mL). Aetiologies of liver diseases were varied: viral hepatitis (44%), alcoholic or non-alcoholic steatohepatitis/cirrhosis (29%), hereditary or auto-immune (12%), and unexplained (15%). 79% of patients saw a fall in cfDNA titre following TACE. Where no reduction was seen, patients had a poorer median overall survival than those who did: 20 months (range 5.13 – 66.7 months) compared to 37 months (9.9 – 79.3 months). Of note, 44% of patients were AFP non-secretors. Here, cfDNA had a clear advantage in disease monitoring, with mean cfDNA titres in this group falling post treatment: from 1605.1 (range 185.9 – 6830) ng/mL to 693.7 (range undetectable - 2300) ng/mL and rising again with subsequent progression (mean of 1329.2 - range 616 – 3341 - ng/mL). Conclusions: These findings support a cost-effective monitoring role for plasma cfDNA analysis following treatment with TACE, with an added advantage in AFP non-secretors. Prospective validation is suggested to fully assess clinical utility.

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