ABSTRACT
Objective@#To establish an analytical method for serum prolactin (PRL) based on the photoinduced chemiluminescence technology, and evaluate its performance. @*Methods@#A pair of PRL monoclonal antibodies were labeled with luminescent nanospheres and biotin respectively, and the double antibody sandwich detection system was formed with the serum prolactin and streptavidin-labeled photosensitive microspheres (universal photosensitive solution) under homogeneous conditions. The performance index and correlation of the detection system were evaluated. @*Results@#The precision of intra-assay and within-day (coefficient of variation) of the developed assay were 4.60% and 5.25%, respectively. The functional sensitivity was 2.48 μIU/mL, and its reportable results were ranged from 2.48 to 4 240 μIU/mL. The recovery rates of different PRL calibrators (42.2, 424, 4 240 μIU/mL) added to human sera were ranged from 96.25% to 102.93%. There was no interference from bilirubin＜20 mg/dL, hemoglobin＜200 mg/dL, triglyceride＜3 000 mg/dL and biotin＜20 ng/mL. Also, the light-initiated chemiluminescent assay for PRL (PRL-LICA) correlated well with Beckman Unicel Dxi 800 Access 2. @*Conclusions@#LICA showed effective performance for detecting PRL in human serum, and it could meet the basic requirements of clinical diagnosis.
ABSTRACT
Objective To develop a competitive immunoassay for quantitative determination of total immunoglobin E (tIgE) in human serum based on light-initiated chemiluminescent assay (LICA).Methods The LICA-tIgE assay was performed by incubating serum samples or calibrator with anti-human IgE antibody-coated chemiluminescet beads,biotinylated human IgE and streptavidin-coated sensitizer beads.The working conditions of this assay were optimized,analytical performance was detected and the correlation of tIgE results between LICA and Beckman Coulter IMMAGE 800 was evaluated.Results The precision of intra-assay and inter-assay (coefficient of variation) ranged from 5.50％ to 7.73％ and 6.45％ to 9.90％,respectively.The functional sensitivity of this assay was 12.65 IU/mL.The recovery rates measured by adding IgE calibrators to human sera with different IgE concentrations were ranged from 104.15％ to 109.37％.The disturbing rates measured by adding total bilirubin,hemoglobin and triacylglycerol to human sera with different IgE concentrations were ranged from-4.49％ to 8.46％.Also,the tIgE results of 111 patients measured by LICA correlated well with those by Beckman Coulter IMMAGE 800 (r2 =0.959).Conclusion LICA developed in this study for detecting tIgE of human serum showed effective perfomance and could meet the basic requirements of clinical diagnostic reagents.
ABSTRACT
Objective To develop europium (Ⅲ) [Eu (Ⅲ)] chelated microparticles for homogeneous immunoassay.Methods Anti-human PCT antibodies were labeled with Eu (Ⅲ) chelated nanoscale microparticles as the detection antibody,and another anti-human PCT antibody was labeled with biotin as the solid-phase antibody.Magnetic microspheres labeled with streptavidin were used to separate the complexes of Eu-IgM-PCT-IgM-Biotin.Results In the homogeneous immunoassay,the standard curve fit was not linear.The quadratic curve was Y =19170.12 + 75493.74X-26.00X2(r =0.9986).According to the standard curve,the limit of detection for PCT was 0.04 ng/ml.Conclusion The homogeneous immunoassay which uses Eu (Ⅲ) chelated microparticles is highly sensitive for detection of PCT recombinant antigens and may serve as a promising method to measure serum PCT levels in the future.
ABSTRACT
Objective:To develop a luminescent oxygen channeling immunoassay for pregnancy associated plasm a protein A.Methods:The monoclonal antibody of PAPP-A was labeled with biotin ,the polyclonal antibody of PAPP-A was coated on receptor particles.The LOCI reagents also contained sensitizer particles coated with streptavidin.The optimal test conditions and analytical per-formance of the method were studied.Results:The within-run and the between-run coefficients of variation were 5.91%-7.94% and 6.14%-9.69%,respectively;the analytical sensitivity was 2.8 mU/L and the function sensitivity was 4.6 mU/L,good linear in 2.8 mU/L-8 000 mU/L range;the recovery rate was 96.7%-100.3%.The interference rate of hemolysis , icterus and triglycerides were less than 10%; there is no Hook effect of PAPP-A concentrations up to 8 000 mU/L;the correlation coefficient between clinical samples detection results and Time resolved fluoroimmunoassay analysis results was 0.974.Conclusion:This LOCI can be used for the quantitative of serum PAPP-A,and detection performance in line with the requirements of clinical diagnostic reagents .
ABSTRACT
Objective To establish homogeneous immunoassay for detecting serum cardiac troponin I (cTnI) by using light induced chemiluminescent immunoassay (LiCA). Methods Polyclonal antibodies of cTnI were coated on the receptor particles, monoclonal antibodies of cTnI were biotinylated, and the donor particles were coated with streptavidin, all of which were composed of LiCA reagents. The optimal test conditions and analytical performance of the detection method were studied. Results The method was rapid, sensitive, and detection time was 17.5 min.The analytical sensitivity was 0.045 ng/mL and the functional sensitivity was 0.053 ng/mL.The recovery rate was 104.96%-108.21%;The within-run and the between-run coefficients of variation were 3.88%-5.53%and 7.60%-8.75%, respectively. The interference rates for the endogenous substances were less than 10%. The reference value of cTnI was less than 1.05 ng/mL;Results of cTnI LiCA correlated well with direct chemiluminescence detection (r2 =0.979). Conclusions This approach can be used for the quantitative detection of serum cTnI, and it is homogeneous and is free of clean separation. It provides a convenient, highly sensitive detection platform for clinical practice.
ABSTRACT
Objective To evaluate reliability of the cloned homogeneous immunoassay technique for detection of P53 protein content in serum and stool from patients with gastric carcinoma. Methods To prepare EA, ED and ED P53 fusion protein of beta galactosidase by PGEX 4T 2 expression vector, a novel cloned homegeneous immunoassay was establishment for detection of P53 protein in serum and stool samples from patients with gastric carcinoma and non gastric carcinoma groups as well as healthy control. Results The concentration of P53 protein in 31 gastric carcinoma subjects were remarkably increased as compared with 56 non gastric carcinoma ( P