Establishment Of Non-Invasive Detection Method For Cys C And ALB In Renal Function Damage Markers By Fluorescence Chromatography

Background:The kidney has no obvious clinical symptoms in the early stage of injury,because of its strong compensatory.When the kidney has obvious symptoms,it is often in the middle and late stage of injury.Therefore,early screening and diagnosis of renal impairment is particularly important for the prognosis of patients.Urinary albumin and cystatin C are important indicators for early screening and adjuvant diagnosis of renal dysfunction,and studies have shown that combined detection two indicators can improve the sensitivity of renal injury detection.At present,the clinical detection of cystatin C and albumin is mainly based on immunoturbidimetry.This method is mainly suitable for large and medium-sized hospitals with relatively complete inspection equipment.It is not suitable for rapid bedside detection at the grassroots or community hospitals,which limits its clinical application.Fluorescence immunochromatography not only meets the needs of rapid bedside detection,but also has the advantages of high sensitivity and easy operation.Detection of cystatin C and albumin by fluorescence immunochromatography has important clinical value in the diagnosis of early renal injury in primary hospital patients.Objective:To establish a new method for rapid and quantitative detection of renal injury markers cystatin C and albumin by optimizing the fluorescent immunochromatography process,which lays a foundation for the clinical application of fluorescence immunochromatography in the detection of such diseases.Methods:1.Reference preparation:Cystatin C and albumin antigen are separately diluted with sample dilution to prepare Cystatin C and albumin indoor reference products.2.Development of urine cystatin C fluorescence immunochromatographic strips(double antibody sandwich principle):the fluorescent microspheres were used to label cystatin C antibody;the sheep anti-mouse IgG was used as quality control line C line,and paired cystatin C antibody was used as detection line T line,and both were coated on the same NC membrane.3.Development of urine albumin fluorescent immunochromatographic test strip(double antibody sandwich principle):the fluorescent microspheres were used to label the albumin antibody;the goat anti-mouse IgG was used as the quality control line C line,and the paired albumin antibody was used as the detection line T line,and both were coated on the same NC membrane.4.Test strip process research and performance evaluation:The main raw materials and processes in the test strip preparation process were screened and optimized,and their performance was evaluated.Results:1.A set of Cystatin C and albumin indoor reference products were prepared.2.A rapid detection method for quantitative detection of urinary cystatin C by fluorescence immunochromatography was established.The linear range of cystatin C detection was 0.05-5 mg/L;the minimum detection limit was 0.03 mg/L;the intra-assay coefficient of variation(CV)of test strips was less than 10%,and the coefficient of variation between batches was less than 15%.The recovery rate of the test strip is between 85%and 115%.The test strips prepared in this study were used to detect 50 samples detected by immunoturbidimetry,which shows that the two methods have a good correlation(R~2=0.9674).3.A rapid detection method for quantitative detection of urinary albumin by fluorescence immunochromatography was established.The linear range of albumin detection was 5-200 mg/L;and the minimum detection limit was 2.5 mg/L;the intra-assay coefficient of variation of test strips was less than 10%,and the coefficient of variation between batches was less than 15%.The recovery rate of the test strip is between 85%and 115%.The test strips prepared in this study were used to detect 50samples detected by immunoturbidimetry.The results showed that the two methods had a good correlation(R~2=0.9796).Conclusion:A rapid and quantitative fluorescence immunochromatographic method for the detection of cystatin C and albumin in human urine has been established,which lays a foundation for the application of fluorescence immunochromatography in the early clinical detection of renal function damage.