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Development of colloidal gold immunochromatographic strip for rapid detection of domoic acid

Gao Li-Li,Cheng Jin-Ping,Liu Yuan-Yuan,Wang Qian,Wang Wen-Hua,

环境科学 , 2011,
Abstract: The colloidal gold immunochromatographic test strip was developed in order to establish a rapid detection assay of Domoic acid (DA) content in marine shellfish. The colloidal gold with particle diameter 20 nm was obtained by reducing gold chloride with sodium citrate. After identification by electron micrograph, optimum conditions for labeling were determined and colloidal gold was labeled by DA monoclonal antibody. The gold-labeled antibody was coated on some chosen glass fiber and dried. The coating antigen (DA-BSA) and Goat anti Mouse IgG were spotted respectively on a piece of nitrate fiber membrane as test line and control line. Finally the test strips were constructed and the detection sensitivity was measured. The results showed that, the detection limit of colloidal gold immunochromatographic test strip was 20 ng/mL and the whole analysis process could be completed within 15 min. The method established is sensitive and the procedure of determination is simple and quick without special equipment. The colloidal gold immunochromatographic test strip could be widely used for batch detection of domoic acid in shellfish on site and has great prospect for commercial development.
Colloidal gold immunochromatographic strip for rapid detection of melamine

Yunfei Gong,Zonglun Chen,Xi Xi,Mujie Li,Weifen Wang,Minzi Wang,Yongfei Ying,Mingzhou Zhang,

生物工程学报 , 2012,
Abstract: To develop a specific, rapid, and convenient immunochromatography assay (ICA) to detect melamine residues in dairy products and feed sample. Colloidal gold particles labeled with purified monoclonal antibody against anti-melamine were used as the detector reagent. The MEL-OVA (the conjugate of melamine and ovalbumin) and goat anti-mouse melamine IgG were blotted on the test and control regions of nitrocellulose membrane. The strip was then assembled with sample pad, absorbing pad, and dorsal shield. The limit of detection (LOD) is 50 mg/L. The test trip was applied to detect melamine in milk, milk powder, and animal feeds, with detection limits of 100 mg/L for milk, 100 ng/g for milk powder, 200 ng/g for feeds. Compared to LC-MS/MS, the ICA could be used to screen a large number of dairy products and feed samples for melamine residue.
Development and evaluation of an immunochromatographic strip for rapid detection of porcine hemagglutinating encephalomyelitis virus
Chen Keyan,Zhao Kui,Song Deguang,He Wenqi
Virology Journal , 2012, DOI: 10.1186/1743-422x-9-172
Abstract: Background The incidence of PHE among pigs in many countries is on the rise, and it has caused great economic losses to the pig industry. Therefore, the development of a sensitive, specific, and easily-performed assay is crucial for the rapid detection and surveillance of PHE-CoV infection and transmission. Results An immunochromatographic strip was developed for the detection of PHE-CoV. The colloidal gold-labeled MAb 4D4 was used as the detection reagent, and the MAb 1E2 and goat anti-mouse IgG coated the strip's test and control lines, respectively. The immunochromatographic strip was capable of specifically detecting PHE-CoV with a HA unit of 2 within 10 min. Storage of the strips at room temperature for 6 months or at 4°C for 12 months did not change their sensitivity or specificity. Using RT-PCR as a reference test, the relative specificity and sensitivity of the immunochromatographic strip were determined to be 100% and 97.78%, respectively. There was an excellent agreement between the results obtained by RT-PCR and the immunochromatographic strips (kappa = 0.976). Additionally, there was a strong agreement between the sandwich enzyme-linked immunosorbent assay (ELISA) and immunochromatographic strips (Kappa = 0.976). When the immunochromatographic strips were used for diagnosing PHE-CoV infection in the Jilin Province, the PHE-CoV-positive rate ranged from 61.54% in the Jilin district to 17.95% in the Songyuan district. Conclusions Based on its high specificity, sensitivity, and stability, the immunochromatographic strip would be suitable for on-site detection of PHE-CoV for surveillance and epidemiological purposes.
A Novel Image Methodology for Interpretation of Gold Immunochromatographic Strip  [cached]
Yurong Li,Nianyin Zeng,Min Du
Journal of Computers , 2011, DOI: 10.4304/jcp.6.3.540-547
Abstract: Gold immunochromatographic strip assay is a rapid, simple, single-copy and on-site method. Quantitative Interpretation of the strip can provide more information than the traditional qualitative or semiquantitative strip assay. The paper aims to develop an image based assay method for quantitative determination of trace concentrations by gold immunochromatographic strip. The image of gold immunochromatographic strip is taken by CCD, and, after the proper filter and window cutting, the test line and control line is segmented by the genetic fast fuzzy c-means(FCM) clustering algorithm. In order to improve the measure property, based on Lambert-beer law, the relative reflective integral optical density(RIOD) is selected as the feature by which the interference in the test and control lines can be canceled out each other. The proposed method is applied to the quantitative detection of human chorionic gonadotropin (hCG) as a model. Firstly, the segmentation performance of the genetic fast FCM clustering algorithm is compared with threshold method and FCM clustering algorithm in terms of the peak signal-to-noise ratio (PSNR). Furthermore, the comparison of the blind experiment between the proposed method and commercial quantitative instrument swp-sc1 is carried out. This method is shown to deliver a result comparable and even superior to existing techniques.
Comparison of an Immunochromatographic Rapid Strip Test, ELISA and PCR in the Diagnosis of Hepatitis C in HIV Patients in Hospital Settings in Cameroon
Clinical Medicine and Diagnostics , 2011, DOI: 10.5923/j.cmd.20110101.04
Abstract: Cameroon belongs to the group of countries highly endemic for hepatitis C viruses. Coinfection of hepatitis C and HIV are also common due to the shared route of transmission of both viruses. In hospital settings in Cameroon, diagnosis prior to treatment of hepatitis C is based solely on the results obtained with an immunochromatographic rapid strip test (97%). This study was aimed at determining the validity of the results that is obtained when an immunochromatographic rapid strip test is used to diagnose hepatitis C virus infection in HIV-positive patients in comparison with more sensitive and specific methods like ELISA and PCR. In a cross-sectional study in two parts, 700 participants were enrolled, 350 were HIV-positive patients and a control group of 350 individuals not infected with HIV. All participants were screened for anti-HCV antibodies using ACON HCV strip test, an assay commonly used in 57·1% of Cameroon hospitals. While using the rapid strip test, of the 350 HIV-positive patients, 25 (7·1%) were found to be positive with the rapid strip test of whom 3(12%) were positive with an ELISA and all 3(100%) positive with the ELISA were also positive with PCR. Evaluation of the rate of false positives with the rapid strip test using ELISA as the gold standard gave a rate of 6·3%. Meanwhile in the control group, after screening with the rapid strip test, 39 (11·1%) were positive of whom 6 (15·4%) were positive with the ELISA and 3 (50%) of the 6 positive with the ELISA were positive with the PCR. Evaluation of the rate of false positives with the rapid strip test in the control group using ELISA as the gold gave a rate of 9·6%. False positive results with this immunochromatographic rapid strip test for the diagnosis of hepatitis C virus infection is therefore common and therefore reinforce the need for a confirmatory test prior to treatment in hospital settings in Cameroon.
Preparation of colloidal gold immunochromatography strip for detection of methamidophos residue

SHI Chenggang,ZHAO Suqing,ZHANG Kun,HONG Guobao,ZHU Zhenyu,

环境科学学报(英文版) , 2008,
Abstract: Methamidophos (Met) is a broad spectrum organophosphorus insecticide and acaricide.Even a trace of its residue is harmful to humans and many animals.In this study,the synthesis and identification of colloidal gold particles and antibody-colloidal gold conjugates were performed,and the preparation of colloidal gold immunochromatography strip was conducted for detection of Met residue.The size of colloidal gold particles was checked using a transmission electron microscope (TEM).The formation of antibody-coll...
Development and validation of a prokaryotically expressed foot-and-mouth disease virus non-structural protein 2C'3AB-based immunochromatographic strip to differentiate between infected and vaccinated animals
Lei Wu, Tao Jiang, Zeng-Jun Lu, Ya-Min Yang, Pu Sun, Zhong Liang, Dong Li, Yuan-Fang Fu, Yi-Mei Cao, Xiang-Tao Liu, Zai-Xin Liu
Virology Journal , 2011, DOI: 10.1186/1743-422x-8-186
Abstract: In this study, an immunochromatographic strip with non-structural protein (NSP) 2C'3AB was developed and validated to differentiate foot-and-mouth disease infected from vaccinated animals. A part of N-terminal of 2C protein gene and whole 3AB gene were connected and prokaryotically expressed as the antigens labeled with colloidal gold was used as the detector, the 2C'3AB protein and rabbits anti-2C'3AB antibodies were blotted on the nitrocellulose(NC) membrane for the test and control lines, respectively. 387 serum samples were collected to evaluate the characteristics of the strip in comparison with existing commercial 3ABC antibody ELISA kit. The coincidence rate of pigs negative serum, pigs vaccinated serum, pigs infected serum was 100%, 97.2%, 95.0%, respectively. The coincidence rate of cattle negative serum, cattle vaccinated serum, cattle infected serum was 100%, 96.7%, 98.0%, respectively. The coincidence rate of sheep negative serum, sheep infected serum was 97.6%, 96.3%, respectively. The strip was shown to be of high specificity and sensitivity, good repeatability and stability.These data suggest that the immunochromatographic strip is a useful tool for rapid on-site diagnosing animals infected foot-and-mouth disease virus.Foot-and-mouth disease (FMD) is an extremely contagious viral disease of cattle, pigs, sheep, goats, and many cloven-hoofed wild animals. The disease is widespread and causes significant economic losses. The causal agent, FMD virus (FMDV), is a positive-sense single-stranded RNA virus that is a member of the genus Aphthovirus in the family Picornaviridae and occurs as seven distinct serotypes throughout the world: A, O, C, Asia1 and South African Territories (SAT) 1-3. The non-structural proteins (NSPs) are conserved amongst the seven serotypes[1,2]. FMDV serotypes O, Asia 1 and A have circulated separately in China during the last fifty years[3-6], and eliminating infected animals and vaccination are the main policies to prevent and co
Kambang Sariadji,Sunarno Sunarno,Nelly P,Melati Wati
Bulletin of Health Research , 2013,
Abstract: . Vibrio cholerae strains are capable of causing outbreak cholera in developing country with poor sanitation and hygiene .Conventional culture methods currently available for detection of V. cholerae 01 takes 3 – 5 days. Other diagnostic tools are by using rapid immunochromatographic strip test for controlling and preventing the spreading of cholera outbreak. This method has limitation in detection of V.cholerae O1, especially under 105 cfu/mL. Furthermore rapid method can be improved by enrichment media and incubation in 37° C for 6 – 8 hours. The aims of research are to analyse enrichments media in increasingl V.cholerae O1, and it’s to improve the finding of the laboratory diagnosis of cholera cases. The research was conducted at the Laboratory of Bacteriology, Center of Biomedical and Basic Technology of Health National Institute of Health Research and Development (NIHRD) from January - July 2011. Medium evaluation was done by making serial dilutions of Vibrio cholerae O1 from 107-101 cfu / ml inoculated into three mediums: alkaline peptone water, bismuth sulfite, and gelatin phosphate salt broth medium. Then were incubated 37°C for 8 hours and every two hours was tested by immunochromatographic strip test. The data analysis to determine treatment and individual differences each group was done by one way ANOVA test. The results showed that alkali peptone water are better than gelatine phosphate salt broth and bismuth sulfite in increasing V.cholerae O1, p.value 0.000 means significant different. Meanwhile from 24 samples dilutions which were inoculated in three enrichment media, and detected by rapid immunochromatographic in every 2 hours for 8 hours showed positive result in enrichments media are 17 samples for alkali peptone water, 13 samples for gelatine phosphate salt broth and 8 samples for bismuth sulfite. Key Words : V.Cholerae, Enrichment Media, Immunochromatographic strip test Abstrak. Vibrio cholerae O1 adalah bakteri yang dapat menimbulkan wabah kolera pada negara berkembang dengan tingkat sanitasi dan higiene yang buruk .Saat ini metode baku diagnosis bakteri V.cholerae O1 adalah dengan kultur dan isolasi yang memerlukan waktu 5 hari. Diagnosis lain untuk menanggulangi dan mencegah penyebaran wabah kolera dengan metode rapid immunokromatografi strip test. Metode rapid ini mempunyai keterbatasan mendeteksi jumlah V.cholerae O1 minimal 105 cfu/mL dan dapat ditingkatkan dengan medium pengayaan yang diinkubasi selama 6 - 8 jam pada suhu 37° C . Penelitian bertujuan untuk menganalisis medium pengayaaan dalam meningkatkan jumlah V
Comparative Evaluation of Immunochromatographic Rapid Diagnostic Tests (Strip and Device) and PCR Methods for Detection of Human Hepatitis B Surface Antigens
Mohammad Hassan Khadem Ansari,Mir Davood Omrani,Vahid Movahedi
Hepatitis Monthly , 2007,
Abstract: Background and Aims: Hepatitis B virus (HBV) infection is a leading cause of liver disease worldwide. It is estimated that approximately 350 million people worldwide have chronic HBV infection. In this study, immunochromatographic assays (ICAs) detection methods including rapid tests were compared with serum HBV-DNA detecting by polymerase chain reaction (PCR) system. Methods: 240 patients including 120 samples that were positive with quantitative PCR method and 120 that were negative by either PCR or EIA methods were selected. Samples were examined by strip and device from Intec, Blue Cross, Acon, Atlas, DIMA and Cortez companies compare to the quantitative PCR method as gold standard for detecting HBsAg.Results: Strip from Intec and Blue Cross, compare to the Acon, Atlas, DIMA and Cortez devices had higher sensitivity in detecting HBsAg in serum. Also positive and negative predictive values of these two strips were higher compare to the rest. In addition true negative value, specificity and positive predictive value of Acon and DIMA strips were higher for detecting HBsAg compare to the rest of the strips.Conclusions: Rapid diagnostic tests are inexpensive, easy to complete, and impose the minimum discomfort to patients, as well as suitable for case-finding and epidemiological surveillance. But it should be considered that negative results with strips or device dose not exclude the presence of HBV DNA and therefore one can be use rapid tests as a back up to standard testing methods. Immunochromatographic results should be interpreted with caution, when the sample has relatively low reactivity by PCR method.
Evaluation of an Immunochromatographic Strip (Xenostrip –Tv) Test for Diagnosis of Vaginal Trichomoniasis Compared with Wet Mount and PCR Assay
S Maraghi,A Khosravi,T Kardooni,T Razi
Iranian Journal of Parasitology , 2008,
Abstract: "nBackground: Trichomoniasis, caused by Trichomonas vaginalis, is one of the most common sexually transmitted infections in the world. Diagnosis of T. vaginalis is performed by different methods, including wet mount, culture, serological methods and PCR, which required laboratory equipments and expert laboratory personnel. The aim of this study was evaluation of immunochromatographic strip test (Xenostrip-Tv) for diagnosis of vaginal trichomoniasis compared with wet mount and PCR assay."nMethods: In this prospective study vaginal swabs were obtained from 100 women with genital complaints demanding a speculum examination, referred to Imam Khomeini and Amir Kabir hospitals in Ahwaz, Khuzestan Province. Samples were first examined by wet mount and Xenostrip-Tv. PCR assay was performed in the next step using TVK3 and TVK7 primers initially. The positive samples were then confirmed by the second PCR assay using TVA5-1 and TVA6 primers."nResults: PCR with TVA5-1 and TVA6 primers was determined as gold standard. The wet mount as well as Xenostrip-Tv sensitivity and specificity were 73.3% and 100%, respectively in comparison with gold standard. The sensitivity and specificity of PCR with primers TVK3 and TVK7 were also determined as 100% and 96.6%, respectively. The infection rates were 14% for wet mount and Xenostrip-Tv, 21% for PCR with primers TVK3 plus TVK7 and 19% with the gold standard PCR using TVA5-1 and TVA6 primers."nConclusion: Xenostrip- Tv could be used for diagnosis of vaginal trichomoniasis in regions with no laboratory diagnostic facilities.
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