• Research in Plant Disease
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• v.23 no.4
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• pp.306-313
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• 2017

Recently fire blight occurred in the Republic of Korea and eradication program for the disease has been executed since then. Specificity and detection sensitivity of the 2 antibody-based diagnostic strips to Korean isolates of Erwinia amylovora (Ea) and their application for on-site diagnosis were evaluated in this study. Ea AgriStrip, a commercial diagnostic kit, and EB strip, developed in this study, reacted positively to the all tested Korean Ea strains and also to most of Erwinia pyrifoliae (Ep) strains causing black shoot blight. They reacted negatively to all Pusedomonas syringae pv. syringae (Pss) strains that cause shoot blight on apple. Detection sensitivity was similar between the 2 strips. For on-site diagnosis, the two strips reacted positively only to the extractions of the fire-blighted samples on all fire blight occurred orchards except one orchard at which on-site diagnosis was carried out at winter time. In addition, they reacted positively to the black-shoot blighted extractions from the black shoot blight occurred apple orchard. These results suggest that both EB strip and Ea AgriStrip would be useful for on-site diagnosis of fire blight in Korea.

• The Plant Pathology Journal
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• v.40 no.4
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• pp.337-345
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• 2024

Soybean (Glycine max L.) is one of the most widely planted and used legumes in the world, being used for food, animal feed products, and industrial production. The soybean mosaic virus (SMV) is the most prevalent virus infecting soybean plants. This study developed a diagnostic method for the rapid and sensitive detection of SMV using a reverse transcription-recombinase polymerase amplification (RT-RPA) technique combined with a lateral flow strip (LFS). The RT-RPA and RT-RPA-LFS conditions to detect the SMV were optimized using the selected primer set that amplified part of the VPg protein gene. The optimized reaction temperature for the RT-RPA primer and RT-RPA-LFS primer used in this study was 38℃ for both, and the minimum reaction time was 10 min and 5 min, respectively. The RT-RPA-LFS was as sensitive as RT-PCR to detect SMV with 10 pg/µl of total RNA. The reliability of the developed RT-RPA-LFS assay was evaluated using leaves collected from soybean fields. The RT-RPA-LFS diagnostic method developed in this study will be useful as a diagnostic method that can quickly and precisely detect SMV in the epidemiological investigation of SMV, in the selection process of SMV-resistant varieties, on local farms with limited resources.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.273-273
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• 2013

Recently, Point-of-care (POC) testing microdevices enable to do the patient monitoring, drug screening, pathogen detection in the outside of hospital. Immunochromatographic strip (ICS) is one of the diagnostic technologies which are widely applied to POC detection. Relatively low cost, simplicity to use, easy interpretations of the diagnostic results and high stability under any circumstances are representative advantages of POC diagnosis. It would provide colorimetric results more conveniently, if the genetic analysis microsystem incorporates the ICS as a detector part. In this work, we develop a reverse transcriptase-polymerase chain reaction (RT-PCR) microfluidic device integrated with a ROSGENE strip for colorimetric influenza H1N1 virus detection. The integrated RT-PCR- ROSGENE device is consist of four functional units which are a pneumatic micropump for sample loading, 2 ${\mu}L$ volume RT-PCR chamber for target gene amplification, a resistance temperature detector (RTD) electrode for temperature control, and a ROSGENE strip for target gene detection. The device was fabricated by combining four layers: First wafer is for RTD microfabrication, the second wafer is for PCR chamber at the bottom and micropump channel on the top, the third is the monolithic PDMS, and the fourth is the manifold for micropump operation. The RT-PCR was performed with subtype specific forward and reverse primers which were labeled with Texas-red, serving as a fluorescent hapten. A biotin-dUTP was used to insert biotin moieties in the PCR amplicons, during the RT-PCR. The RT-PCR amplicons were loaded in the sample application area, and they were conjugated with Au NP-labeled hapten-antibody. The test band embedded with streptavidins captures the biotin labeled amplicons and we can see violet colorimetric signals if the target gene was amplified with the control line. The off-chip RT-PCR amplicons of the influenza H1N1 virus were analyzed with a ROSGENE strip in comparison with an agarose gel electrophoresis. The intensities of test line was proportional to the template quantity and the detection sensitivity of the strip was better than that of the agarose gel. The test band of the ROSGENE strip could be observed with only 10 copies of a RNA template by the naked eyes. For the on-chip RT-PCR-ROSGENE experiments, a RT-PCR cocktail was injected into the chamber from the inlet reservoir to the waste outlet by the micro-pump actuation. After filling without bubbles inside the chamber, a RT-PCR thermal cycling was executed for 2 hours with all the microvalves closed to isolate the PCR chamber. After thermal cycling, the RT-PCR product was delivered to the attached ROSGENE strip through the outlet reservoir. After dropping 40 ${\mu}L$ of an eluant buffer at the end of the strip, the violet test line was detected as a H1N1 virus indicator, while the negative experiment only revealed a control line and while the positive experiment a control and a test line was appeared.

• Journal of Biomedical Engineering Research
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• v.7 no.1
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• pp.35-40
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• 1986

For quantitative measurement of reflected light from a clinical diagnostic strip, a prototype old reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate reflectance parameters. The strip was illuminated at 45˚c through optical fiber and the intensity of reflected light was determined at rectanguLat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500, 550, 570 and 610nm) for blood glucose strip. For higher concentration than 300mg/41 about glucose, a saturation state of abforbance was observed at 500, 550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.471-472
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• 2009

• Clinical and Experimental Pediatrics
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• v.51 no.10
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• pp.1071-1076
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• 2008

Purpose : Respiratory syncytial virus (RSV) is the most frequent cause of lower respiratory infections in infants and young children. Early detection allows quarantining of infected inpatients to prevent nosocomial transmission and to choose a treatment. To achieve rapid reporting, to facilitate prompt antiviral therapy, and to avoid unnecessary use of antibiotics, an easy, rapid diagnostic method for RSV is needed. We evaluated a lateral flow immunochromatography (RSV Respi-Strip test) and EIA (Enzyme immuno assay) compared to RT-PCR. Methods : From April 2007 to March 2008, 112 consecutive respiratory specimens (nasopharyngeal aspirates, throat swabs, tracheal aspirates, sputum) from patients who were suffering from the clinical signs and symptoms of respiratory tract infection were enrolled in Busan. A total of 112 patients were tested with RSV Respi-Strip (Corio-BioConcept, Belgium), EIA, and RT-PCR at the same time. Results : Of the 112 specimens tested, the number of children who showed positive results at RT-PCR and Respi-Strip were 45 and 42, respectively. The Respi-Strip rapid antigen test had a sensitivity of 88% and a specificity of 94%. The positive and negative predictive values were 90% and 92%, respectively. The agreement was 83%. Conclusion : In our study, the rapid antigen test had as much sensitivity as any method for detection of RSV. The test has many advantages such as easy performance, simple interpretation, and rapid results. If the rapid antigen test is widely applied in the clinical setting, the may be useful for diagnostic and epidemiological studies of RSV infection.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.339-344
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• 2003

Paraquat is an effective and widely used herbicide, but it is also very toxic to humans. It is well-known that urine paraquat concentration is one of the most important prognostic indicator for paraquat-poisoning. Quantitative analysis of paraquat, however, are not generally used in clinical laboratories. In this work, a new test strip to detect paraquat concentration using sodium dithionite in urine was developed. Using these second-derivative method, the test strip prepared in $0.5{\%}$ borate buffer (pH 8.0), 0.25 M $Na_2S_2O_4,\0.1~0.8{\%}$ PVP, and $1{\%}$ decanol showed not only better color reaction but also an excellent application possibility to be used in automatic analyzer.

• Journal of Biomedical Engineering Research
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• v.13 no.4
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• pp.299-306
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• 1992

For quantitative measurement of reflected light from a clinical diagnostic scrip, a prototype of reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate re(leclance parameters. The strop was illuminated at $45^{\circ}C$ through optical fiber and the intensity of reflected light was determined at rectangulat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500,550,570 and 610nm) for blood glucose strip. For higher concentration than 300mg/dl about glucose, a saturation state of absorbance was observed at 500,550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.144-147
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• 1992

In this paper, we study about reflectance photometer for measuring teflectance changes on reagent strip material after applying of a liguid sample. To obtain more accurate reflectance parameter, the strip loader and cassette is designed. The system is designed to work with IBM personal computer. As the experimental results, reflectance level measured of korean standard color paper and shows a exponentially proportion to brightness of paper. A diagnostic strip for total protein is applied to our system and shows a good correlation in a physically protein concentration range.(up to 500 mg/dl).

• Journal of Veterinary Science
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• v.21 no.4
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• pp.68.1-68.8
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• 2020

A fluorescent microsphere-based immunochromatographic strip test (FICT) was developed for the rapid, sensitive, and quantitative detection of porcine reproductive and respiratory syndrome virus (PRRSV) antibodies at the pen-side. The assay was based on the formation of a sandwich immune-complex (anti-pig IgG-PRRSV antibodies-NSP7/N), which was validated by a comparison with IDEXX-ELISA using 3325 clinical specimens. The diagnostic specificity, sensitivity, and accuracy of FICT were 97.28, 93.41, and 94.95%, respectively. FICT showed a good correlation with the virus neutralization assay. Overall, a promising pen-side diagnostic tool was developed for the rapid and quantitative detection of PRRSV antibodies within 15 min.