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Enzyme-linked immunosorbent assays (ELISA) specific for anti-HSV glycoprotein G (gG) are most commonly used in the clinical diagnosis of HSV infection. But most of them are qualitative and with narrow detection ranges. A novel time-resolved fluoroimmunoassay (TRFIA) methodology was developed for the quantitative determination of HSV IgG in human serum. The assay was based on an indirect immunoassay format, and performed in 96-well microtiter plates. HSV-1 and HSV-2 were used as the coating antigens. Eu3+-labeled goat anti-(human IgG) polyclonal antibodies were used as tracers. The fluorescence intensity of each well was measured and serum HSV IgG levels quantified against a calibration curve. The detection range of the novel TRFIA was between 5 and 500 AU/mL. Assay sensitivity was 0.568 AU/mL. The intra- and inter-assay coefficients of variation were 0.59-3.63% and 3.65-6.81%, respectively. Analytical recovery, dilution tests and serum panel tests were performed using TRFIA and the results proved satisfactory. There were no statistically significant differences in sensitivity and specificity between the TRFIA and commercial ELISAs. An effective, sensitive and accurate quantitative HSV type 1 and type 2 IgG TRFIA was successfully developed and provided diagnostic value in clinical use. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Current clinically assays, such as enzyme‐linked immunosorbent assay and chemiluminescence immunoassay, for hepatitis B surface antigen (HBsAg) are inferior in terms of either sensitivity and accuracy or rapid and high‐throughput analysis. A novel assay based on magnetic beads and time‐resolved fluoroimmunoassay was developed for the quantitative determination of HBsAg in human serum. HBsAg was captured using two types of anti‐HBsAg monoclonal antibodies (B028, S015) immobilized on to magnetic beads and detected using europium‐labeled anti‐HBsAg polyclonal detection antibody. Finally, the assay yielded a high sensitivity (0.02 IU/mL) and a wide dynamic range (0.02–700 IU/mL) for HBsAg when performed under optimal conditions. Satisfactory accuracy, recovery and specificity were also demonstrated. The intra‐ and interassay coefficients of variation were 4.7–8.7% and 3.8–7.5%, respectively. The performance of this assay was further assessed against a well‐established commercial chemiluminescence immunoassay kit with 399 clinical serum samples. It was revealed that the test results for the two methods were in good correlation (Y = 1.182X – 0.017, R = 0.989). In the current study, we demonstrated that this novel time‐resolved fluoroimmunoassay could be used: as a highly sensitive, automated and high‐throughput immunoassay for the diagnosis of acute or chronic hepatitis B virus infection; for the screening of blood or organ donors; and for the surveillance of persons at risk of acquiring or transmitting hepatitis B virus. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Time-resolved fluorometry of lanthanide chelates is one of the most useful non-isotopic detection techniques and has been used in numerous applications in biomedical science. We developed a time-resolved fluoroimmunoassay (TRFIA) to quantify α-fetoprotein (AFP) and hepatitis B virus surface antigen (HBsAg) in human serum. Based on a two-site sandwich protocol, monoclonal antibodies (McAbs) against AFP and HBsAg were co-coated in 96 microtitration wells and tracer McAbs against HBsAg and AFP were labeled with europium (Eu) and samarium (Sm) chelates, respectively. After application of diluted serum samples, Eu3+- and Sm3+-McAbs were added and fluorescence signals of Sm3+ and Eu3+ tracers were collected. Detection limits of AFP and HBsAg were 0.09 mIU/L and 0.01 µg/L, respectively. Measurement ranges of AFP-TRFIA and HBsAg-TRFIA were 1-1000 mIU/L and 0.2-150 µg/L, respectively. Intra- and inter-assay coefficients of variation of AFP-TRFIA were 3.3-4.1% and 5.7-7.2% and for HBsAg-TRFIA were 2.9-3.9% and 4.9-6.8%, respectively. Linear correlation of TRFIA and chemiluminescence immunoassay measurements resulted in a correlation coefficient of 0.9949 for AFP and 0.9940 for HBsAg. For the endurance test, Eu-labeled McAbs were stable for at least one year at −20°C and the results of the TRFIA with the same reagents were also reproducible after one year. The availability of a highly sensitive, reliable and convenient AFP/HBsAg TRFIA will allow the quantification of both AFP and HBsAg, thereby providing diagnostic value in various clinical conditions and could be applied for clinical use. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Using diammonium hydrogen phosphate as an activator and N and P source and and bamboo chips as the carbon source, N, P co-doped activated carbon was prepared by one-step pyrolysis and used to efficiently remove La 3+ in aqueous solutions. The effects of activation temperature and pH value on the adsorption performance of La 3+ were analyzed, and the activation and adsorption mechanisms were explored using TG-IR, SEM-EDX, pore structure, XPS, and hydrophilicity. The results showed that diammonium hydrogen phosphate easily decomposed at a high temperature to produce ammonia and phosphoric acid, which activated the material and promoted the increase in the specific surface area and pore volume of the activated carbon. As an N and P source, the addition of diammonium hydrogen phosphate successfully achieved the N, P co-doping of activated carbon, and the introduction of N- and P-containing functional groups was the key to enhance the adsorption of La 3+ . Among them, graphitic nitrogen could provide interactions between La 3+ -π bonds, and C-P=O and C/P-O-P could provide active sites for the adsorption of La 3+ through complexation and electrostatic interaction. The adsorption of La 3+ on N, P co-doped activated carbons was endothermic and spontaneous, and the adsorption process conformed to the Langmuir isotherm and secondary kinetic model. Under the process conditions of an activation temperature of 900℃ and pH=6, the adsorption capacity of the N, P co-doped activated carbon was as high as 55.18 mg·g -1 , which was 2.53 times higher than that of the undoped sample, and its adsorption selectivity for La 3+ in the La 3+ /Na + and La 3+ /Ca 2+ coexistence systems reached 93.49% and 82.49%, respectively. Additionally, the removal efficiency remained above 54% after five successive adsorption-desorption cycle experiments.

Enzyme-linked immunosorbent assays (ELISA) specific for anti-HSV glycoprotein G (gG) are most commonly used in the clinical diagnosis of HSV infection. But most of them are qualitative and with narrow detection ranges. A novel time-resolved fluoroimmunoassay (TRFIA) methodology was developed for the quantitative determination of HSV IgG in human serum. The assay was based on an indirect immunoassay format, and performed in 96-well microtiter plates. HSV-1 and HSV-2 were used as the coating antigens. Eu(3+)-labeled goat anti-(human IgG) polyclonal antibodies were used as tracers. The fluorescence intensity of each well was measured and serum HSV IgG levels quantified against a calibration curve. The detection range of the novel TRFIA was between 5 and 500 AU/mL. Assay sensitivity was 0.568 AU/mL. The intra- and inter-assay coefficients of variation were 0.59-3.63% and 3.65-6.81%, respectively. Analytical recovery, dilution tests and serum panel tests were performed using TRFIA and the results proved satisfactory. There were no statistically significant differences in sensitivity and specificity between the TRFIA and commercial ELISAs. An effective, sensitive and accurate quantitative HSV type 1 and type 2 IgG TRFIA was successfully developed and provided diagnostic value in clinical use., (Copyright © 2014 John Wiley & Sons, Ltd.)

Current clinically assays, such as enzyme-linked immunosorbent assay and chemiluminescence immunoassay, for hepatitis B surface antigen (HBsAg) are inferior in terms of either sensitivity and accuracy or rapid and high-throughput analysis. A novel assay based on magnetic beads and time-resolved fluoroimmunoassay was developed for the quantitative determination of HBsAg in human serum. HBsAg was captured using two types of anti-HBsAg monoclonal antibodies (B028, S015) immobilized on to magnetic beads and detected using europium-labeled anti-HBsAg polyclonal detection antibody. Finally, the assay yielded a high sensitivity (0.02 IU/mL) and a wide dynamic range (0.02-700 IU/mL) for HBsAg when performed under optimal conditions. Satisfactory accuracy, recovery and specificity were also demonstrated. The intra- and interassay coefficients of variation were 4.7-8.7% and 3.8-7.5%, respectively. The performance of this assay was further assessed against a well-established commercial chemiluminescence immunoassay kit with 399 clinical serum samples. It was revealed that the test results for the two methods were in good correlation (Y = 1.182X - 0.017, R = 0.989). In the current study, we demonstrated that this novel time-resolved fluoroimmunoassay could be used: as a highly sensitive, automated and high-throughput immunoassay for the diagnosis of acute or chronic hepatitis B virus infection; for the screening of blood or organ donors; and for the surveillance of persons at risk of acquiring or transmitting hepatitis B virus., (Copyright © 2013 John Wiley & Sons, Ltd.)

Time-resolved fluorometry of lanthanide chelates is one of the most useful non-isotopic detection techniques and has been used in numerous applications in biomedical science. We developed a time-resolved fluoroimmunoassay (TRFIA) to quantify α-fetoprotein (AFP) and hepatitis B virus surface antigen (HBsAg) in human serum. Based on a two-site sandwich protocol, monoclonal antibodies (McAbs) against AFP and HBsAg were co-coated in 96 microtitration wells and tracer McAbs against HBsAg and AFP were labeled with europium (Eu) and samarium (Sm) chelates, respectively. After application of diluted serum samples, Eu(3+)- and Sm(3+)-McAbs were added and fluorescence signals of Sm(3+) and Eu(3+) tracers were collected. Detection limits of AFP and HBsAg were 0.09 mIU/L and 0.01 µg/L, respectively. Measurement ranges of AFP-TRFIA and HBsAg-TRFIA were 1-1000 mIU/L and 0.2-150 µg/L, respectively. Intra- and inter-assay coefficients of variation of AFP-TRFIA were 3.3-4.1% and 5.7-7.2% and for HBsAg-TRFIA were 2.9-3.9% and 4.9-6.8%, respectively. Linear correlation of TRFIA and chemiluminescence immunoassay measurements resulted in a correlation coefficient of 0.9949 for AFP and 0.9940 for HBsAg. For the endurance test, Eu-labeled McAbs were stable for at least one year at -20°C and the results of the TRFIA with the same reagents were also reproducible after one year. The availability of a highly sensitive, reliable and convenient AFP/HBsAg TRFIA will allow the quantification of both AFP and HBsAg, thereby providing diagnostic value in various clinical conditions and could be applied for clinical use., (Copyright © 2012 John Wiley & Sons, Ltd.)

Objective: To develop a time-resolved fluoroimmunoassay (TRFIA) for detection of pertussis toxin (PT) S1 subunit for quality control of human PT vaccine., Methods: A double antibody sandwich one-step method was used to establish the TRFIA for detecting PT S1 subunit in the vaccine., Results: The sensitivity of c peptide analysis reached 2.5 ng/ml without cross-reactions with other antigens. This assay could be used in detecting S1 subunit in the vaccine., Conclusion: The TRFIA for detecting PT S1 subunit is simple, sensitive and rapid for quality control of the PT vaccine.

Objective: To develop an amplified luminescent proximity homogeneous immunoassay (AlphaLISA) kit for the detection of human hepatitis B virus e antibody (HBeAb)., Methods: The neutralizing and competitive inhibition method was used to develop the AlphaLISA kit for detection of serum HBeAb., Results: The working range of the kit was 0.003-16 NCU/ml with a sensitivity up to 0.003 NCU/ml. The intra- and inter-assay coefficient of variation was 5.3% and 6.8%, respectively. The kit showed no cross-reaction with HBcAb, and comparison of the detection results with those of a commercially available Elecsys HBeAb kit (Roche) for 136 samples showed a correlation coefficient of 0.961., Conclusion: The AlphaLISA kit for HBeAb detection meets the clinical requirements for detection HBeAb in human serum.