1.Application study of novel quantum dot fluorescence immunochromatography for the determination of serum amyloid A
International Journal of Laboratory Medicine 2024;45(16):2010-2016,2022
Objective To investigate the application of novel quantum dot fluorescence immunochromatog-raphy for the determination of serum amyloid A(SAA).Methods Using the principle of double antibody sandwich method and quantum dots fluorescence immunochromatography technology to prepare SAA detec-tion kit with Dinitrophenol(DNP)-Bovine serum albumin(BSA)system as the control line.The feasibility of using the DNP-BSA system as a quality control line was evaluated using the chicken IgY-sheep anti-chicken IgY system as a control,and further improve the performance of the reagent kit by optimizing the coupling conditions between quantum dot microspheres and antibodies.Evaluated the blank limit,detection limit,linear range precision,accuracy,specificity,stability,as well as clinical samples determination of the kit.Results The SAA kit using DNP-BSA system as the quality control line was less affected by the concentration of inter-fering components,had high stability,and good thermal stability.The optimal coupling effect was achieved when the coupling ratio between quantum dots and SAA antibodies was 100 μg/mg,and the coupling reaction solution was 25 mmol/L 3-morpholine propyl sulfonate pH 7.4,and the coupling ratio with DNP-BSA was 100 μg/mg and the coupling reaction solution was 25 mmol/L morpholine ethanesulfonate pH 6.0.The detec-tion limit of SAA kit was 0.5 mg/L;the linear range was 1-200 mg/L,R2≥0.99;the intra assay precision variation coefficient(CV%)≤5.31%,and the inter assay precision CV%≤15%;the recoveries in the low,and high concentrations were 101.42%and 98.83%,respectively.When hemoglobin concentration ≤5 g/L,bilirubin concentration ≤0.15 g/L,cholesterol concentration ≤15 g/L,triglyceride concentration ≤10 g/L,SAA detection results had no interference.The stability of the kit was good when it was stored at 50 ℃ for 21 days.The kit is highly consistent with that of Roche's SAA electrochemiluminescence kit in the simultaneous detection of 67 samples.Conclusion The sensitivity,linearity,precision,accuracy,specificity and accelerated stability of the SAA detection kit can meet the requirements of the kit.Compared with Chicken IgY-sheep an-ti-chicken IgY,DNP-BSA system has better independence as quality control line,and has better accuracy and thermal stability.