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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.

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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.

Antibiotic residues, generated by the irrational use of drugs and environmental pollution, have always been a great challenge to aquaculture safety. Therefore, a quick, convenient, and performance-excellent way to detect antibiotic residues in aquaculture fish is urgently required. In this study, a multiplex immunochromatographic strip biosensor based on gold nanoparticles was developed for the simultaneous detection of five classes of antibiotic residues (24 β-lactam antibiotics, 26 sulfonamides, five tetracyclines, 24 quinolones, and four amphenicols) in aquaculture fish within 10 min. The detection ranges of five representative antibiotics, penicillin G, sulfamethazine, tetracycline, enrofloxacin, and chloramphenicol, were 2.33–38.4, 0.688–17.1, 1.4–48.1, 1.45–32.9, and 0.537–9.06 µg/kg, respectively. The accuracy and stability of these measurements were demonstrated by analyzing spiked fish samples, with recovery rates of 87.5%–115.2% and a coefficient of variation < 9.5%. The cross-reaction rates, based on the five representative antibiotics, were 3.77%–202% for β-lactams, 3.95%–137% for sulfonamides, 9.19%–100% for tetracyclines, 4.9%–145% for quinolones, and 3.2%–100% for amphenicols. The excellent testing performance of the biosensor strip to most of antibiotic residues in aquaculture fish ensures they meet the maximum residue limits required by countries or organizations. Therefore, this multiplex immunochromatographic strip biosensor is potentially applicable to the rapidly on-site determination of antibiotic residues in aquaculture fish. [ABSTRACT FROM AUTHOR]

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.

Straightforward genotyping can provide timely diagnostic information for diseases prevention and treatment. Taking advantages of speediness and convenience, although numerous genotyping strategies combined loop-mediated isothermal amplification (LAMP) and lateral flow have been reported to satisfy the demand of point-of-care test, the false positive result caused by aerosol and primer dimer as an innate conflict seriously limits their practical application. In this study, both aerosol and primer dimer as extrinsic and intrinsic inducements respectively are first broken through at one stroke based on an integrated immunochromatographic biosensor. By introducing digoxigenin labeled dUTP into LAMP, not only the amplicon can be analyzed through naked eye, but also the aerosol contamination can be eliminated thoroughly by uracil DNA glycosylase ignoring the open vessel. Primer dimer, the significant drawback in lateral flow-based strategies, has been overcome due to the bio-labeled deoxyribonucleotide and oligonucleotide cannot couple for signal generation even under the high primer concentration. Instead of colloidal gold, the gold magnetic nanoparticle is synthesized and assembled into this biosensor as a nanoprobe, which enables the result to be quantified by the magnetic signal for subjective bias elimination. The polymorphism of C677T in methylenetetrahydrofolate reductase, a crucial genetic code related to folate metabolism, is genotyped using saliva as noninvasive specimen dispense with DNA purification. Only 1 ng genomic DNA can provide accurate result within 25 min by a simple heater, which proves the potential of this biosensor to facilitate precision medicine., Competing Interests: Declaration of competing interest 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., (Copyright © 2024 Elsevier B.V. All rights reserved.)

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.

A fluorescent immunochromatographic test (FM-ICT) was developed for rapid detection of anti- Orientia tsutsugamushi antibodies in serum samples. The FM-ICT was constructed based on the dual-antigen sandwich method. Truncated 56 kDa outer membrane protein of O. tsutsugamushi strain SJ, was expressed in E. coli and mixed with those of Ptan and Gillam strains. A thin line of the protein mixture was precisely sprayed across a nitrocellulose membrane making this the "Test" line. Polyclonal antibodies (pAbs) to O.tsutsugamushi were sprayed in another line across the membrane making this the "Control" line. Fluorescent microspheres conjugated 56 kDa proteins reacting with sample serum will be captured on the "Test" line if the sample contains antibodies to O.tsutsugamushi. Several experimental parameters were optimized. After optimizing the reaction procedure, the results are visible, within 6 min, with the naked eye under ultraviolet light. The limit of detection (LOD) was determined to be 7.63 ng/mL with prepared polyclonal antibodies. No cross-reaction was observed with sera samples from other febrile diseases. In clinical evaluations, the strips showed 94.92% sensitivity (106/112) and 93.75% specificity (56/60). The FM-ICT we developed will provide a new tool for on-site diagnosis of scrub typhus. • Recombinant proteins of three epidemic strains were mixed as diagnostic antigen. • Fuorescent microsphere were used in immunochromatographic strip for lower LOD. • Results can be read by naked eyes with the help of a portable UV lamp. • Suitable for on-site diagnosis in lab, families, even in the wild or remote areas. [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.

Results of three rapid immunochromatographic tests (ICTs) were compared with those obtained with two automated immunoassays for evaluation of their usefulness. One hundred fifty-nine patients and 67 healthy volunteers were included. Different assays demonstrate 41–45% of diagnostic sensitivities and 91–98% of specificities, with substantial agreement (89.3–91.2%), but a high percentage of weak positive results (13–22%) was observed with ICTs. ICTs performances were comparable to those of automated immunoassays. ICTs could have a role as screening approach due to their easy usability. Subjective interpretation, significant rate of uncertain results, uncertainty on viral antigens source are undoubtedly drawbacks. [ABSTRACT FROM AUTHOR]

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]

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Peste des petits ruminants virus (PPRV) causes a very devastating disease in sheep and goats. Rapid diagnosis and immunisation have been identified as key strategies for successful prevention of the disease. Therefore, a sensitive fluorescent microsphere immunochromatography test strips (FM-ICTS) was developed for rapid detection of special antibodies of PPRV in goats and sheep serum. The FM-ICTS were successfully prepared by fluorescent microspheres (FM) as tracer, which were covalently coupled to PPRV nucleocapsid protein (NP). The NP and monoclonal antibody of NP were separately dispensed onto a nitrocellulose membrane as test and quality control lines, respectively. The critical threshold for determining negative or positive through the ratio of the fluorescent signal of the test line and the control line (T/C) is 0.050. The repeatability of the FM-ICTS was excellent, with an overall average CV of 3.17 %. The detection limit of this assay was 1:5120. Additionally, the FM-ICTS no cross reaction with the sera of other related diseases was observed, only reacting with anti-PPRV serum. 70 serum samples were tested by FM-ICTS and commercial ELISA kit, and the results showed good agreement. Overall, a promising pen-side diagnostic tool was developed for the rapid qualitatively/semi-quantitatively detection of PPRV antibodies within 15 min. • We developed an FM-ICTS approach that can identify antibodies against PPRV. • The FM-ICTS is capable of detecting various types of antibodies in serum, including IgG and IgM. • The FM-ICTS assay can be used as a tool to assess the effects of vaccine immunization after vaccination. [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).)

A quantitative immunochromatographic assay (QIA) was developed by using gold nanoparticle (GNP)-based lateral flow strip biosensor (LFSB) and a portable strip reader for rapid and sensitive quantitation of Carbohydrate Antigen 19-9 (CA 19-9) in human plasma. CA 19-9 is a biomarker that has been associated with cancers (such as pancreatic and colorectal cancers) and various non-cancerous diseases. The principle is based on sandwich-type immunoreactions between gold nanoparticle (GNP)-labelled detection antibody, anti-CA 19-9 capture antibody and CA 19-9to capture the GNPs on the test zone of LFSB. The accumulation of GNPs on the test zone gave a red line whose intensity was read with a portable strip reader to quantify the concentration of CA 19-9. Assay parameters including the membrane type, antibody concentration, amount of GNP-anti-CA 19-9 conjugates and the components of the running buffer were optimized to obtain the best sensitivity and reproducibility of the assay. The detection limit of the assay was determined to be 5 U mL −1 (S/N = 3) with a linear range of 5 U mL −1 –100 U mL −1 . CA 19-9 concentrations in healthy human and pancreatic cancer patient plasma samples were successfully evaluated using the developed quantitative immunochromatographic assay (QIA), and the results were in accordance with that obtained with enzyme linked immunosorbent assay (ELISA). The developed assay shows great promise for clinical application and biomedical diagnosis, particularly in limited resource settings. [ABSTRACT FROM AUTHOR]

Highlights • The cT of wild-type rotavirus is lower than Rotarix (median 12.43 verses 29.09). • The limit of detection of the Combi-Strip (Coris, BioConcept) is about Ct 18. • Real-time RT-PCR is more sensitive than an immunochromatographic method. Abstract Background Diagnosis of wild-type rotavirus disease may be complicated by the detection of vaccine-derived virus which can be detected in stool samples following immunisation. We evaluate an immunochromatographic assay and real-time RT-PCR to determine which is more suitable for the detection of wild-type rotavirus. Objectives To compare the Ct values of wild-type rotavirus and Rotarix determined by real-time RT-PCR. To establish the Ct value corresponding to the limit of detection of the immunochromatographic Combi-Strip method (Coris, BioConcept). Study design Retrospective review of real-time RT-PCR Ct values was performed on 100 samples tested by a pan-rotavirus assay (n = 50 wild-type, n = 50 Rotarix). Secondly the limit of detection of the Combi-Strip assay was determined by testing; wild-type rotavirus (n = 33, Ct range 6.85–34.26) samples, Rotarix (n = 9, Ct range 20.86–34.26) samples and rotavirus negative (n = 21) samples. Results The median Ct of 50 wild-type rotavirus was Ct 12.43; range 6.11–32.66 compared with the median of 50 Rotarix, Ct 29.09; range 18.91–35.28, p=<0.0001. The limit of detection of the Combi-Strip method was approximately Ct 18. The 21 rotavirus negative samples were negative by real-time RT-PCR and Combi-Strip. Conclusions We found the Ct value was significantly lower, and therefore the viral load higher, for wild-type rotavirus compared to detectable Rotarix. The Combi-Strip assay detects most wild-type infections; however, it lacks sensitivity to detect low-level wild-type rotavirus and, beneficially, is unlikely to detect Rotarix. It is not a more suitable method than real-time RT-PCR when a definitive rotavirus result is required. [ABSTRACT FROM AUTHOR]

Introduction Mulberroside A (MuA) is the major active anti-tyrosinase compound in the root bark extract of Morus alba L. (Moraceae). Typically, MuA is widely employed as an active ingredient in whitening cosmetics. A rapid and simple assay system utilizing a small quantity of test sample is essential for the detection of MuA in large number of samples. An immunoassay using highly specific MuA polyclonal antibodies may be useful for the determination of small quantities of MuA in test samples. Objective To establish a rapid qualitative MuA test, an immunochromatographic strip test was developed using anti-MuA polyclonal antibodies (anti-MuA PAb). Methodology The qualitative assay was based on a competitive immunoassay where the detection reagent consisted of anti-MuA PAb colored with colloidal gold particles. The capture reagent was a MuA-ovalbumin (MuA-OVA) conjugate immobilized on the test strip membrane. Results A sample containing MuA and the detection reagent were incubated together with immobilized capture reagent on a nitrocellulose membrane. When MuA was present, it competed with the immobilized conjugates on the strip membrane to bind a limited amount of colored antibodies; thus, a positive sample showed no color on the capture spot zone. The detection limit for the strip test was 2 µg/mL. The developed immunochromatographic strip test was utilized to determine MuA in plants, medical preparations and cosmetic samples. Conclusion This immunochromatographic strip test is advantageous as a rapid, simple and sensitive screening method for the detection of MuA in plant extracts, cosmetic samples and pharmaceutical products. [ABSTRACT FROM AUTHOR]

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]

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.)

[Display omitted] • Based on competitive immunoassay and SERS a rapid and highly sensitive method for the detection of bisphenol A in water was established. • The detection limitation was 0.1pg/mL. • This method shows broad prospects for applications in the fields of biomedical diagnosis and food safety monitoring. Sensitive and selective detection of target analyte is very important in many fields such as commodity inspection and quality monitoring. In this work, based on the principle of competitive immunoassay, surface-enhanced Raman spectroscopy (SERS) was used to establish a rapid and highly sensitive method for the detection of trace amounts of bisphenol A in water. Here, Raman molecule 5,5-dithiobis-2-nitrobenzoic acid and anti-BPA antibody were conjugated with Au (core)@Ag (shell) nanoparticle to serve as SERS nanoprobe. After the SERS nanoprobe is combined with the substance to be tested, it uses the siphon effect to pass through the test line and the charging line on the test strip. And the Raman test was performed on the T line with a Raman spectrometer. The detection limitation was 0.1 pg/mL. Compared with the reported gas chromatography, liquid chromatography, fluorescence analysis, and other detection methods, SERS ICA does not demand complicated sample preparation procedures, and has the advantages of simple detection methods, quick results, High sensitivity, good specificity, and low technical demands for laboratory environment and testers. In addition, Raman spectrometers have gradually developed to be portable, making it easier to meet the needs of on-site rapid and highly sensitive detection, and will show broad prospects for applications in the fields of biomedical diagnosis and food safety monitoring. [ABSTRACT FROM AUTHOR]