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Introduction: Sub-Saharan Africa struggles continuously with insufficient resources and inadequate infrastructure that hinder the establishment of a safer blood supply despite improvements in transfusion safety over recent decades. This study aimed to evaluate the impact of the chemiluminescence technique in combination with immunoenzymatic and immunochromatographic tests for viral marker screening of hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV) in donated blood in a country of sub-Saharan Africa. Method: This study was conducted in a population of 113,406 blood donors at the National Centre of Blood Transfusion in Senegal. The data were obtained from the ‘INLOG’ software and donor registers. Statistical analyses used Excel 2010 and Epi Info v6. Screening for HBsAg viral markers, anti-HCV Ab, HIV p24 Ag, anti-HIV1 and anti-HIV2 antibodies were first carried out using the chemiluminescence technique. Blood donations screened positive for HBV or HCV were retested in a second chemiluminescence equipment. HIV-positive donations and their controls were subjected to solid phase immunochromatographic and indirect enzyme immunoassay techniques. Results: The prevalence among donors of HBV was 8.39 %, 0.56 % for HCV and 0.18 % for HIV. Of the donors tested positive for HIV in screenings and in doubled-controls, only 61.54 % were confirmed by the alternative tests; 34.02 % were negative and 4.44 % discordant between the three techniques. Conclusion: This study shows the importance of introducing the chemiluminescence technique in association with serological screening of transfusion-transmitted viruses to improve blood supply safety in low-income countries.

Photothermal immunochromatographic sensor is an emerging detection technology, and it is important to develop new sensing probes with excellent photothermal performance to improve its detection performance. In the present study, a novel photothermal sensing probe based on violet phosphorus nanosheets with satisfactory photothermal conversion efficiency (31.1 %) was reported for the first time. A photothermal immunochromatographic sensor using the above probe was applied for visual and photothermal detection of diethylstilbestrol. The diethylstilbestrol concentration was inversely proportional to photothermal sensing signal and showed a good linear correlation in the range of 0.75 ∼ 50 μg·L−1. After optimizing, the visual and photothermal detection limits were 6 μg·L−1 and 0.56 μg·L−1, respectively. The recovery rates in tap water, milk and pork samples ranged from 82.2 % to 115.2 %, with a coefficient of variation (CV) ranging from 2.0 % to 10.8 %. This work not only structured a new type of photothermal probe, but also expanded the application range of violet phosphorus.

Immunochromatographic Test Strip (ICTS), a detection technology based on capillary column chromatography and specific immune interaction between antibody and antigen, is widely utilized in the field of rapid detection of food safety detection due to its cost-effectiveness, easy operation, non-professional personnel, short assay time, high specificity and naked eye visualization. Conventional spherical gold nanoparticles-based ICTS is the most common detection method. However, the conventional ICTS can help achieve simple qualitative or semiquantitative analysis, its low sensitivity is an obstacle to meet the current detection requirements. Therefore, there has been a growing interest focusing on the signal amplification method to improve the sensitivity of ICTS devices. This paper summarizes signal amplification strategies to enhance the sensitivity of ICTS and proposes the future perspectives, which provides technical references for the development of rapid detection methods for food safety.

ABSTRACT: Enrofloxacin, a veterinary antibiotic that persists in food, poses a risk to human health. Here, a monoclonal antibody against enrofloxacin, 1H12, was prepared based on the hapten ENR-1, and showed excellent sensitivity with a 50% inhibitory concentration (IC50) of 0.03 ng/mL. Using this antibody, 2 lateral-flow immunochromatographic assays were developed for determination of enrofloxacin in egg, milk, honey, and chicken meat samples. The detection ranges (IC20–IC80) were 0.16–0.82 ng/g, 0.24–1.8 ng/g, 0.25–3.6 ng/g, and 0.61–3.9 ng/g by colloidal gold-immunochromatographic sensor (CG-ICS) analysis, and 0.022–0.42 ng/g, 0.054–0.42 ng/g, 0.069–1.4 ng/g, and 0.19–2.2 ng/g by Eu-fluorescence-immunochromatographic sensor (EF-ICS) analysis. The intraassay and interassay recovery rates were 88.9 to 108.5% with coefficients of variation of 1.3 to 7.0% by CG-ICS analysis, and 88.6 to 113.6% with coefficients of variation of 1.3 to 8.1% by EF-ICS analysis. Thus, our newly developed ICS are sensitive and reliable, providing an option for rapid quantitative detection of enrofloxacin in food samples.

Introduction: Sub-Saharan Africa struggles continuously with insufficient resources and inadequate infrastructure that hinder the establishment of a safer blood supply despite improvements in transfusion safety over recent decades. This study aimed to evaluate the impact of the chemiluminescence technique in combination with immunoenzymatic and immunochromatographic tests for viral marker screening of hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV) in donated blood in a country of sub-Saharan Africa., Method: This study was conducted in a population of 113,406 blood donors at the National Centre of Blood Transfusion in Senegal. The data were obtained from the 'INLOG' software and donor registers. Statistical analyses used Excel 2010 and Epi Info v6. Screening for HBsAg viral markers, anti-HCV Ab, HIV p24 Ag, anti-HIV1 and anti-HIV2 antibodies were first carried out using the chemiluminescence technique. Blood donations screened positive for HBV or HCV were retested in a second chemiluminescence equipment. HIV-positive donations and their controls were subjected to solid phase immunochromatographic and indirect enzyme immunoassay techniques., Results: The prevalence among donors of HBV was 8.39 %, 0.56 % for HCV and 0.18 % for HIV. Of the donors tested positive for HIV in screenings and in doubled-controls, only 61.54 % were confirmed by the alternative tests; 34.02 % were negative and 4.44 % discordant between the three techniques., Conclusion: This study shows the importance of introducing the chemiluminescence technique in association with serological screening of transfusion-transmitted viruses to improve blood supply safety in low-income countries., Competing Interests: Conflicts of interest The authors declare that they have no competing interest., (Copyright © 2024 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier España, S.L.U. All rights reserved.)

BackgroundFasciola gigantica, a tropical liver fluke, infects buffalo in Asian and African countries, causing significant economic losses and posing public health threats. The diagnostic of buffalo fascioliasis caused by F. gigantica is vital in fascioliasis control and preventation. The 22nd gel filtration chromatography fraction of F. gigantica Excretory-Secretory Products (FgESP), namely Fasciola 22 (F22), which was used as a diagnostic antigen in indirect ELISA, has demonstrated great potential for fascioliasis diagnosing. In the absence of rapid diagnostic methods, the use of a colloidal gold immunochromatographic strip based on F22 was applied to detect F. gigantica infection in buffalo.MethodsIn the present study, the 22nd gel filtration chromatography fraction of FgESP (F22) was used as an antigen to establish the colloidal gold-based immunochromatographic strip (ICS). The nitrocellulose membrane was incubated with F22 at the test line (T line) and goat anti-mouse secondary antibody at the control line (C line). The mouse anti-buffalo secondary antibody 2G7 conjugated to colloidal gold particles was used as the detection system for line visualization. The strip was assembled and developed by optimizing reaction conditions. The sensitivity, specificity, stability, and early diagnostic value of the strip were evaluated employing buffalo-derived sera.ResultsAn immunochromatographic strip for the rapid detection of antibodies against F. gigantica-FgICS was developed. The strip demonstrated high sensitivity and specificity. Sensitivity tests confirmed positive results even when the positive reference serum was diluted 4,096 times. Except for one Schistosoma japonicum-positive serum that tested positive via FgICS, specificity tests confirmed no cross-reactivity with other positive sera of Schistosoma japonicum and Babesia bovis. The strip remained stable after storage at 4°C for up to 3 months. In infected buffalo, antibodies could be detected as early as 14–21 days post-infection. The detection of 17 positive sera yielded an 82.4% positive rate via FgICS vs. a 100.0% positive rate via ELISA based on FgESP. For FgICS, the 95% confidence interval of sensitivity was 84.8–95.4%, while specificity was 4.2–14.7%.ConclusionThe immunochromatographic strip FgICS developed in this study provides a simple and rapid method of F. gigantica antibody detection and infected buffalo monitoring in the field.

This mini review presents the standard methods for the analytical identification of virus species. These methods have been trusted and known as accredited methods. The development of new and improved analytical techniques is important to overcome the lack and the drawbacks of the well-known methods. Due to the uncertain and unprecedented time of pandemic, new approaches with high performance in the analysis are needed to retain the required and growing diagnostic tools complementary to real-time polymerase chain reaction (RT-PCR) for COVID-19 diagnosis. The researchers are still developing direct methods for the detection of SARS-CoV-2 in a short turnaround time. The process of analytical validation is an important part of experimentation that is needed for the developed methods to be trusted. This review presents the major standard, commercial and designed methods for detecting SARS-CoV-2 and their analytical performance. Also, chromatographic techniques have been introduced as a rapid examination for SARS-CoV-2 identification, and the newly developed assays have been addressed.

Enrofloxacin, a veterinary antibiotic that persists in food, poses a risk to human health. Here, a monoclonal antibody against enrofloxacin, 1H12, was prepared based on the hapten ENR-1, and showed excellent sensitivity with a 50% inhibitory concentration (IC 50) of 0.03 ng/mL. Using this antibody, 2 lateral-flow immunochromatographic assays were developed for determination of enrofloxacin in egg, milk, honey, and chicken meat samples. The detection ranges (IC 20 –IC 80) were 0.16–0.82 ng/g, 0.24–1.8 ng/g, 0.25–3.6 ng/g, and 0.61–3.9 ng/g by colloidal gold-immunochromatographic sensor (CG-ICS) analysis, and 0.022–0.42 ng/g, 0.054–0.42 ng/g, 0.069–1.4 ng/g, and 0.19–2.2 ng/g by Eu-fluorescence-immunochromatographic sensor (EF-ICS) analysis. The intraassay and interassay recovery rates were 88.9 to 108.5% with coefficients of variation of 1.3 to 7.0% by CG-ICS analysis, and 88.6 to 113.6% with coefficients of variation of 1.3 to 8.1% by EF-ICS analysis. Thus, our newly developed ICS are sensitive and reliable, providing an option for rapid quantitative detection of enrofloxacin in food samples. [ABSTRACT FROM AUTHOR]

Tricaine (TMS) is usually used as an anesthetic in the transportation of aquatic animals. However, when consumed, the numerous residual drug residues found in fish can cause a high risk to human health. Therefore, it is important to develop a rapid and sensitive method for the detection of this drug in food. Here we have developed a novel lateral-flow immunochromatographic strip (LF-ICS) method for the detection of TMS in fish samples, using a very effective anti-TMS monoclonal antibody with a half-maximal inhibitory concentration value of 31.79 ng/mL. After the K2CO3 and coating antigen concentrations were optimized in phosphate buffered saline (pH 7.4), the LF-ICS was used to determine TMS levels in fish samples spiked with varying concentrations of the drug. Following this, the values for the visual limit of detection and the cut-off for TMS were found to be less than 0.1 and 1 μg/mL, respectively. These results indicated that our developed LF-ICS is applicable for on-site screening of TMS in fish samples.

Objective: To develop a new sandwich based lateral flow immunochromatographic strip for rapid detection of circulating Schistosoma mansoni antigen in serum and urine samples of patients with active schistosomiasis. Methods: This lateral flow immunochromatographic strip was prepared by using anti-Schistosoma mansoni soluble egg antigen monoclonal antibody conjugated gold nanoparticles (MAb-AuNPs) as antigen-detecting antibody, while crystalline material (MCM)-41-MAb bioconjugate was immobilized at the test line as antigen-capturing antibody. Both antigen capturing and detecting antibodies formed sandwich complexes with circulating Schistosoma mansoni antigen in the positive samples. Sandwich complexes immobilized at the test line gave distinct red color. The assay reliability was examined by using urine and serum samples of 60 Schistosoma mansoni infected patients, 20 patients infected with parasites other than Schistosoma, and 20 healthy individuals as negative controls. Results were compared with those obtained via sandwich enzyme linked immunosorbent assay (ELISA). Results: The detection limit of circulating Schistosoma mansoni antigen by lateral flow immunochromatographic strip was lower (3 ng/mL) than the detection limit by ELISA (30 ng/mL). The sensitivity and specificity of lateral flow immunochromatographic strip in urine samples were 98.3% and 97.5%, respectively compared to 93.5% and 90.0% by ELISA. In serum samples, they were 100.0% and 97.5%, respectively compared to 97.0% and 95.0% by ELISA. The strip test took approximately 10 min to complete. Conclusions: This new lateral flow immunochromatographic strip offers a sensitive, rapid, and field applicable technique for diagnosis of active schistosomiasis.

This mini review presents the standard methods for the analytical identification of virus species. These methods have been trusted and known as accredited methods. The development of new and improved analytical techniques is important to overcome the lack and the drawbacks of the well-known methods. Due to the uncertain and unprecedented time of pandemic, new approaches with high performance in the analysis are needed to retain the required and growing diagnostic tools complementary to real-time polymerase chain reaction (RT-PCR) for COVID-19 diagnosis. The researchers are still developing direct methods for the detection of SARS-CoV-2 in a short turnaround time. The process of analytical validation is an important part of experimentation that is needed for the developed methods to be trusted. This review presents the major standard, commercial and designed methods for detecting SARS-CoV-2 and their analytical performance. Also, chromatographic techniques have been introduced as a rapid examination for SARS-CoV-2 identification, and the newly developed assays have been addressed. [ABSTRACT FROM AUTHOR]

PurposeTo develop a rapid detection reagent for SARS-CoV-2 antigen for the auxiliary diagnosis of new coronary pneumonia (COVID-19), and perform the methodological evaluation and clinical evaluation of the reagent.MethodSARS-CoV-2 N-protein test strip was created by combining fluorescent microsphere labeling technology and immunochromatographic technology, based on the principle of double antibody sandwich. Then we evaluated the analytical capability and clinical application of the strips.ResultThe limit of detection of the strips for recombinant N protein was 100 ng/ml and for activated SARS -CoV-2 virus was 1 × 103 TCID50/ml. The strips also have high analytical specificity and anti-interference capability. According to the predetermined cut-off value, the specificity of the test strip in healthy controls and patients with other respiratory disease was 100.00 and 97.29%, the sensitivity in COVID-19 cases at progress stage and cured stage was 67.15 and 7.02%. The positive percentage agreement and negative percentage agreement of antigen strip to RNA test were 83.16 and 94.45%.ConclusionSARS-CoV-2 fluorescence immunochromatographic test strip can achieve fast, sensitive and accurate detection, which can meet the clinical requirements for rapid detection of viruses on the spot.

Tricaine (TMS) is usually used as an anesthetic in the transportation of aquatic animals. However, when consumed, the numerous residual drug residues found in fish can cause a high risk to human health. Therefore, it is important to develop a rapid and sensitive method for the detection of this drug in food. Here we have developed a novel lateral-flow immunochromatographic strip (LF-ICS) method for the detection of TMS in fish samples, using a very effective anti-TMS monoclonal antibody with a half-maximal inhibitory concentration value of 31.79 ng/mL. After the K2CO3 and coating antigen concentrations were optimized in phosphate buffered saline (pH 7.4), the LF-ICS was used to determine TMS levels in fish samples spiked with varying concentrations of the drug. Following this, the values for the visual limit of detection and the cut-off for TMS were found to be less than 0.1 and 1 μg/mL, respectively. These results indicated that our developed LF-ICS is applicable for on-site screening of TMS in fish samples. [ABSTRACT FROM AUTHOR]

Purpose: To develop a rapid detection reagent for SARS-CoV-2 antigen for the auxiliary diagnosis of new coronary pneumonia (COVID-19), and perform the methodological evaluation and clinical evaluation of the reagent. Method: SARS-CoV-2 N-protein test strip was created by combining fluorescent microsphere labeling technology and immunochromatographic technology, based on the principle of double antibody sandwich. Then we evaluated the analytical capability and clinical application of the strips. Result: The limit of detection of the strips for recombinant N protein was 100 ng/ml and for activated SARS -CoV-2 virus was 1 × 103 TCID50/ml. The strips also have high analytical specificity and anti-interference capability. According to the predetermined cut-off value, the specificity of the test strip in healthy controls and patients with other respiratory disease was 100.00 and 97.29%, the sensitivity in COVID-19 cases at progress stage and cured stage was 67.15 and 7.02%. The positive percentage agreement and negative percentage agreement of antigen strip to RNA test were 83.16 and 94.45%. Conclusion: SARS-CoV-2 fluorescence immunochromatographic test strip can achieve fast, sensitive and accurate detection, which can meet the clinical requirements for rapid detection of viruses on the spot. [ABSTRACT FROM AUTHOR]

Antecedentes: el parvovirus canino (CPV) es un virus altamente contagioso que afecta el tracto gastrointestinal principalmente en cachorros‚ y es el agente causal de un síndrome caracterizado por vómito y diarrea hemorrágica severa. Este virus fue descubierto a finales de los años 70 y desde entonces se ha caracterizado por ser una problemática en perros a nivel mundial. Objetivo: determinar la seroprevalencia de la parvovirosis canina en EJELAB®‚ en los municipios de Pereira y Dosquebradas entre los años 2017 y 2019. Métodos: en un estudio descriptivo transversal se analizaron 39 muestras sanguíneas‚ clasificando los datos según el sexo y la procedencia. Las muestras se procesaron mediante el kit ANIGEN® rapid CPV Ag test. La prueba tiene un 100 % de sensibilidad y un 98,5 % de especificidad. Las variables cualitativas se analizaron mediante estadística descriptiva y Chi cuadrado. Para el análisis estadístico se usó el programa JASP Team (2020). JASP (Versión 0‚12‚2‚0). Resultados: se obtuvieron un total de 39 datos. Positivos para CPV: 38,4 %‚ n = 15; pacientes negativos para CPV: 61,6 %‚ n = 24. Se determinó la asociación entre la procedencia de las muestras y la seropositividad mediante el estadístico chi cuadrado‚ p = 0,94; p > 0,05‚ indicando que no hay diferencia significativa (Pacientes positivos para CPV en Pereira 86,6 %; n = 13; Pacientes positivos para CPV Dosquebradas 13,4 %; n = 2). No hay asociación entre la seropositividad y el sexo de los caninos‚ Chi cuadrado p = 0,217; p > 0,05. Conclusiones: se puede inferir que el sexo no influye en la seropositividad. Se obtuvo una seronegatividad del 61,6 %; este resultado podría atribuirse al avance en el desarrollo de las vacunas‚ lo que genera una inmunidad activa artificial eficaz para el CPV. La baja solicitud del servicio diagnóstico entre los años 2017 y 2019 de CPV sugiere que hay una baja manifestación de los reportes de enfermedad en las localidades donde se desarrolló el estudio. Los tutores de los caninos han adquirido una mejor educación relacionada con la tenencia responsable de mascotas y la importancia de llevar a cabo los planes de inmunización sugeridos por los médicos veterinarios. [ABSTRACT FROM AUTHOR]

Objective: To develop a new sandwich based lateral flow immunochromatographic strip for rapid detection of circulating Schistosoma mansoni antigen in serum and urine samples of patients with active schistosomiasis. Methods: This lateral flow immunochromatographic strip was prepared by using anti-Schistosoma mansoni soluble egg antigen monoclonal antibody conjugated gold nanoparticles (MAb-AuNPs) as antigen-detecting antibody, while crystalline material (MCM)-41-MAb bioconjugate was immobilized at the test line as antigen-capturing antibody. Both antigen capturing and detecting antibodies formed sandwich complexes with circulating Schistosoma mansoni antigen in the positive samples. Sandwich complexes immobilized at the test line gave distinct red color. The assay reliability was examined by using urine and serum samples of 60 Schistosoma mansoni infected patients, 20 patients infected with parasites other than Schistosoma, and 20 healthy individuals as negative controls. Results were compared with those obtained via sandwich enzyme linked immunosorbent assay (ELISA). Results: The detection limit of circulating Schistosoma mansoni antigen by lateral flow immunochromatographic strip was lower (3 ng/mL) than the detection limit by ELISA (30 ng/mL). The sensitivity and specificity of lateral flow immunochromatographic strip in urine samples were 98.3% and 97.5%, respectively compared to 93.5% and 90.0% by ELISA. In serum samples, they were 100.0% and 97.5%, respectively compared to 97.0% and 95.0% by ELISA. The strip test took approximately 10 min to complete. Conclusions: This new lateral flow immunochromatographic strip offers a sensitive, rapid, and field applicable technique for diagnosis of active schistosomiasis. [ABSTRACT FROM AUTHOR]

Twenty pellet broiler feed samples (started or finished) were collected through October to December 2013, from 12 broiler flocks and 8 feed mills in Nineveh governorate, for the detection of Aflatoxins residue using total Aflatoxins rapid test strips kit. Results show that 3 (15%) of the feed samples were positive while 17 feed samples (85%) were negative to residual Aflatoxin.

Aim: Detection of rabies is a cause of serious concern in developing countries, where dearth of highly equipped laboratories and trained personnel to handle sophisticated investigations is felt. The availability of a diagnostic kit, which can be used in the field, is essential for diagnosis and control programs as well as for epidemiological surveillance of the prevalence of the disease. This study was planned to evaluate anigen rabies Ag test kit for its efficacy to be used for rapid diagnosis of rabies under field conditions. The test results were compared with hemi-nested reverse transcriptase polymerase chain reaction and with a gold standard fluorescent antibody test. Materials and Methods: A total of 34 brain samples from different rabies suspected animals including dogs, buffaloes, cow, horse, and cat were examined in this study. Results: Sensitivity of the kit was found to be 91.66%, specificity 100%, and accuracy was 94.11%. Conclusion: The study implies that the immunochromatographic diagnostic test kit may be employed for diagnosis of rabies in field conditions.

Photothermal immunochromatographic sensor is an emerging detection technology, and it is important to develop new sensing probes with excellent photothermal performance to improve its detection performance. In the present study, a novel photothermal sensing probe based on violet phosphorus nanosheets with satisfactory photothermal conversion efficiency (31.1 %) was reported for the first time. A photothermal immunochromatographic sensor using the above probe was applied for visual and photothermal detection of diethylstilbestrol. The diethylstilbestrol concentration was inversely proportional to photothermal sensing signal and showed a good linear correlation in the range of 0.75 ∼ 50 μg·L -1 . After optimizing, the visual and photothermal detection limits were 6 μg·L -1 and 0.56 μg·L -1 , respectively. The recovery rates in tap water, milk and pork samples ranged from 82.2 % to 115.2 %, with a coefficient of variation (CV) ranging from 2.0 % to 10.8 %. This work not only structured a new type of photothermal probe, but also expanded the application range of violet phosphorus., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)

Aim: To assess the diagnostic value of the Immunochromatographic Assay (ICA) for serodiagnosis of bovine brucellosis and comparing results with those obtained from Rose Bengal Plate Test (RBPT) and Indirect Enzyme Linked Immunsorbent Assay (iELISA). Materials and Methods: In this study, 40 bovine sera were subjected to serological tests for bovine brucellosis using RBPT, iELISA and ICA using Anigen Rapid B. Brucella Ab test kit. Results: Out of the 40 bovine sera examined, antibody against Brucella were detected in 24 (60%), 27 (67.5%) and 20 (50%) samples by by RBPT, iELISA and ICA respectively. The kappa value between iELISA and ICA was 0.45 and that between RBPT and iELISA was 0.53. The sensitivity for RBPT and ICA was (76%) and (59.26%) respectively while specificity was (57.14%) and (80%) for these two tests respectively. Conclusion: These findings indicated that ICA was more specific than RBPT while the latter was more sensitive. Both tests showed almost moderate agreement.

Aim: Detection of rabies is a cause of serious concern in developing countries, where dearth of highly equipped laboratories and trained personnel to handle sophisticated investigations is felt. The availability of a diagnostic kit, which can be used in the field, is essential for diagnosis and control programs as well as for epidemiological surveillance of the prevalence of the disease. This study was planned to evaluate anigen rabies Ag test kit for its efficacy to be used for rapid diagnosis of rabies under field conditions. The test results were compared with hemi-nested reverse transcriptase polymerase chain reaction and with a gold standard fluorescent antibody test. Materials and Methods: A total of 34 brain samples from different rabies suspected animals including dogs, buffaloes, cow, horse, and cat were examined in this study. Results: Sensitivity of the kit was found to be 91.66%, specificity 100%, and accuracy was 94.11%. Conclusion: The study implies that the immunochromatographic diagnostic test kit may be employed for diagnosis of rabies in field conditions. [ABSTRACT FROM AUTHOR]

Twenty pellet broiler feed samples (started or finished) were collected through Oc tober to December 2013 , from 12 broiler flocks and 8 feed mills in Nineveh governorate, for the detection of Aflatoxins residue using total Aflatoxins rapid test strip s kit. Results show that 3 (15%) of the feed samples were positive while 17 feed samples (85%) were negative to residual Aflatoxin. [ABSTRACT FROM AUTHOR]

Backgrround:: Cholera is gastroenteritis caused by enterotoxin producing Vibrio cholera. Cholera is predominantly a waterborne disease especially in countries with inadequate sanitation. Several rapid methods have been developed and used to detect V. cholerae serotypes directly from stools. Objjecttiives:: to evaluate a rapid and accurate method for the diagnosis of cholera caused by V. cholerae O1 and O139 serogroups d to find the incidence of sporadic cases of cholera in Baghdad. Metthods:: Sixty four stool samples were collected from four hospitals in Baghdad. The age of patients ranging from two months to 12 years, 26 were females and 38 males. Immunochromatographic visual test for qualitative detection of O1 and /or O139 serogroups was used as well as routine culture procedure for isolation of V. cholerae. Resulltts:: Immunochromatographic visual test shows that, out of 64 stool samples only 16 was positive (23.4%). Fifteen of them belong to O1 serotype and one belong O139 serotype. Stool sample culture on alkaline peptone water and then on Thiosulfate Citrate Bile salts Sucrose (TCBS) agar enhance the growth of 11(68.75%) V. cholerae isolates out of 16 that were positive by using immunochromatographic visual test. Sensitivity of culture and immunochromatographic test was 68.75% and 100% respectively. Concllusiions:: V. cholerae O1 is more predominant than V. cholerae O139 among V. cholerae strains isolated from sporadic cases of cholera in Baghdad. Immunochromatographic test is rapid, accurate and more sensitive than culture method in recover V. cholerae strains.

This study evaluated the BD Veritor system for rapid detection of SARS-CoV-2, an immunochromatographic point-of-care test, by comparing it with a standard reverse transcription-PCR (RT-PCR) methodology using samples from symptomatic patients. Samples from 146 symptomatic and 2 asymptomatic patients between the 1st and the 40th day of infection were evaluated. The nasopharyngeal and/or oropharyngeal swabs were inserted in a tube containing 0.9% saline solution and stored at refrigerator temperature until the moment of use. The samples were first tested with the Xpert Xpress SARS-CoV-2 (GeneXpert) kit (RT-PCR method), and the cycle thresholds ( C T s) for the E and N2 genes encoding the SARS-CoV-2 envelope and nucleoprotein, respectively, were established. Subsequently, the same samples were tested using the Veritor rapid test. We analyzed the C T s of the N2 gene, which is detected in both methodologies, and observed sensitivities of 100%, 98.8%, 89.6%, and 82.7% for the C T s of <25, <27, and <30 and all the C T s, respectively. The greatest sensitivity was observed when we performed the test on patients within 5 days of symptom onset. The BD Veritor system's workflow is simple and fast, taking approximately 16 min from sample preparation to obtaining the test result. In addition to its satisfactory sensitivity, with results that correlate with those of the RT-PCR, the BD Veritor analyzer instrument reduces the subjectivity of unaided visual readings and consequent potential variation in result interpretation. Therefore, our results showed that the BD Veritor diagnostic test can provide a rapid and accurate diagnosis for SARS-CoV-2. IMPORTANCE This study provides important and useful information, especially for diagnostic laboratories, since the results show that the BD Veritor system can provide a fast and safe point-of-care antigen diagnostic test for rapid detection of COVID-19 that has high sensitivity, reproducibility, and accuracy.

Background: Fasciola gigantica , a tropical liver fluke, infects buffalo in Asian and African countries, causing significant economic losses and posing public health threats. The diagnostic of buffalo fascioliasis caused by F. gigantica is vital in fascioliasis control and preventation. The 22nd gel filtration chromatography fraction of F. gigantica Excretory-Secretory Products ( Fg ESP), namely Fasciola 22 (F22), which was used as a diagnostic antigen in indirect ELISA, has demonstrated great potential for fascioliasis diagnosing. In the absence of rapid diagnostic methods, the use of a colloidal gold immunochromatographic strip based on F22 was applied to detect F. gigantica infection in buffalo., Methods: In the present study, the 22 nd gel filtration chromatography fraction of Fg ESP (F22) was used as an antigen to establish the colloidal gold-based immunochromatographic strip (ICS). The nitrocellulose membrane was incubated with F22 at the test line (T line) and goat anti-mouse secondary antibody at the control line (C line). The mouse anti-buffalo secondary antibody 2G7 conjugated to colloidal gold particles was used as the detection system for line visualization. The strip was assembled and developed by optimizing reaction conditions. The sensitivity, specificity, stability, and early diagnostic value of the strip were evaluated employing buffalo-derived sera., Results: An immunochromatographic strip for the rapid detection of antibodies against F. gigantica - Fg ICS was developed. The strip demonstrated high sensitivity and specificity. Sensitivity tests confirmed positive results even when the positive reference serum was diluted 4,096 times. Except for one Schistosoma japonicum -positive serum that tested positive via Fg ICS, specificity tests confirmed no cross-reactivity with other positive sera of Schistosoma japonicum and Babesia bovis . The strip remained stable after storage at 4°C for up to 3 months. In infected buffalo, antibodies could be detected as early as 14-21 days post-infection. The detection of 17 positive sera yielded an 82.4% positive rate via Fg ICS vs. a 100.0% positive rate via ELISA based on Fg ESP. For Fg ICS, the 95% confidence interval of sensitivity was 84.8-95.4%, while specificity was 4.2-14.7%., Conclusion: The immunochromatographic strip Fg ICS developed in this study provides a simple and rapid method of F. gigantica antibody detection and infected buffalo monitoring in the field., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, He, Wu, Jin, Wu, Guo, Zhang and Di.)

An immunochromatographic lateral flow dipstick assay for the fast detection of microcystin-LR was developed. Colloid gold particles with diameters of 40 nm were used as red-colored antibody labels for the visual detection of the antigen. The new dipstick sensor is capable of detecting down to 5 µg·l−1 (ppb; total inversion of the color signal) or 1 ppb (observation of color grading) of microcystin-LR. The course of the labeling reaction was observed via spectrometric wave shifts caused by the change of particle size during the binding of antibodies. Different stabilizing reagents showed that especially bovine serum albumin (BSA) and casein increase the assays sensitivity and the conjugate stability. Performance of the dipsticks was quantified by pattern processing of capture zone CCD images. Storage stability of dipsticks and conjugate suspensions over 115 days under different conditions were monitored. The ready-to-use dipsticks were successfully tested with microcystin-LR-spiked samples of outdoor drinking- and salt water and applied to the tissue of microcystin-fed mussels. [ABSTRACT FROM AUTHOR]

An immunochromatographic strip test has been developed for detecting ginsenosides Rb1 (G-Rb1) and Rg1 (G-Rg1). This qualitative assay system is useful as a rapid screening method for detecting G-Rb1 and G-Rg1 in plants and plant preparations. Our assay is a competitive immunoassay that uses anti-G-Rb1 and anti-G-Rg1 monoclonal antibodies (MAbs) and a detection reagent that contains colloidal gold particles coated with anti-G-Rb1 and anti-G-Rg1 MAbs. Detection limits are 2 μg mL-1 for both G-Rb1 and G-Rg1. [ABSTRACT FROM AUTHOR]

Aim: To assess the diagnostic value of the Immunochromatographic Assay (ICA) for serodiagnosis of bovine brucellosis and comparing results with those obtained from Rose Bengal Plate Test (RBPT) and Indirect Enzyme Linked Immunsorbent Assay (iELISA). Materials and Methods: In this study, 40 bovine sera were subjected to serological tests for bovine brucellosis using RBPT, iELISA and ICAusing Anigen Rapid B. Brucella Ab test kit. Results: Out of the 40 bovine sera examined, antibodies againstBrucellawere detectedin 24 (60%), 27(67.5%) and20 (50%) samples by by RBPT, iELISA and ICA respectively. The kappa value between iELISA and ICA was 0.45 and that between RBPT and iELISA was 0.53. The sensitivity for RBPT and ICA was (76%) and (59.26%) respectively while specificity was (57.14%) and (80%) for these two tests respectively. Conclusion: These findings indicated that ICA was more specific than RBPT while the latter was more sensitive. Both tests showed almost moderate agreement. [ABSTRACT FROM AUTHOR]

Chlamydia trachomatis is the most common sexually transmitted bacterial infection worldwide, with the highest prevalence in sexually active young women. Since most chlamydial infections are asymptomatic, facilitating the transmission of the pathogen in the population, regular screening is recommended for at-risk sexually active individuals. Hence, a sensitive, specific, inexpensive diagnostic test that can be executed efficiently and quickly to yield results would be helpful. In this study, we evaluated the performance (sensitivity and specificity) of the Chlamydia Rapid Test Device, an inexpensive rapid test based on immunochromatographic analysis. We then compared these results to those obtained using real-time PCR, the gold standard for C. trachomatis testing. Seminal fluid and urine specimens of male subjects were tested. The rapid test was applied to 220 seminal fluid samples, showing a sensitivity of 0%. On the other hand, used in 114 urine specimens, the rapid test showed 37.5% and 100% sensitivity and specificity, respectively. Hence, the Chlamydia Rapid Test Device was shown to be insufficiently sensitive to be recommended as a screening test and diagnostic method for the detection of C. trachomatis in symptomatic and asymptomatic subjects. Finally, the present investigation showed an infection prevalence of 5% calculated using seminal fluid, with a mean age of 28 years., Competing Interests: Conflicts of interest The authors declare that they have no conflict of interest., (Copyright © 2016 - 2021 InfezMed.)

Recent studies suggest that celiac disease is common in many developing countries. Taking into account the disease may be underdiagnosed in Cuba, the main objectives of this study were to assess the presence of celiac disease related to antibodies in a cohort of apparently healthy children from Pinar del Río province and to evaluate a new rapid test for detecting celiac disease antibody in blood, serum and plasma samples. A total of 595 apparently healthy children with no record of first degree relatives suffering from celiac disease, were screened for Tissue transglutaminase antibodies by one-step immunochromatographic. The results were compared with commercials ELISA kits. In the study seven subjects (1.18%) were identified as positive by immunochomatographic assay and by Celikey IgG Antibody Assay with a 100% of concordance and only five subjects (0.84%) by Celikey IgA Antibody Assay. The achievement of the intestinal biopsy was offered to all positive individuals. This study demonstrates that one-step immunochromatographic assay is an appropriate tool to detect celiac disease-associated to antibodies and provides further evidence of the prevalence of possible undiagnosed celiac disease among healthy children in Cuba. [ABSTRACT FROM AUTHOR]