Establishment Of The Quantitative Detection Method Of Colloidal Gold Immunochromatography For D-Dimer

BackgroundD-two polymer(D-Dimer, D-D) is the specific degradation products of cross-linked fibrin(Fb) after the action of fibrinolytic enzyme,which can be used as a molecular marker of high coagulation and fibrinolysis invivo and is the only reflection of coagulation and fibrinolysis ideal index.When suffering from thrombotic diseases and pulmonary embolism?Disseminated intravascular coagulation(DIC)?heart cerebrovascular disease(CCVd)?Liver diseases and neoplastic disease,the concentration of D-Dimer in our body will be significantly increased.Especially,the content of D-Dimer has a very important clinical diagnostic value of exclusion in excluding diagnosis of pulmonary embolism and deep vein thrombosis.In addition,the increasing of the concentration of D-Dimer has an extremely close relationship with the occurrence?development and prognosis of many diseases,such as acute pancreatitis?diabetic vascular disease and acute and chronic urticaria.Consequently, the detection of D-Dimer in plasma has a very important clinical significance for the auxiliary diagnosis and prognosis monitoring of a variety of diseases.At present,the methods of detecting D-Dimer mainly include Latex agglutination?Enzyme linked immunosorbent assay(ELISA)?Immune turbidity method and Colloidal gold immunoassay. The mainly clinical application is Immune turbidity method now.Nevertheless,though these advantages of the method such as that quantization is precise?high sensitivity?good reproducibility of reagent?high stability,it can not achieve rapid detection and need large instruments and equipments, resulting in the limit popularity of D-Dimer in the primary hospitals. Therefore,we need a detection method that is fast,easy to operate and quantitative accuracy for the detection of D-Dimer urgently in order to make detection of D-Dimer universal. However,Quantitative detection of colloidal gold immunochromatography has these advantages,and then make up for the deficiencies above.In recent years,with the development and maturity of the colloidal gold immunochromatography,the detecting technique has been developed from the qualitative to both qualitative and quantitative and has been used in the detection of a variety of substance more and more widely.With its unique advantages,it is expected to be used in the quantitative detection of D-Dimer. ObjectiveTo establish the colloidal gold immune chromatography assay for the quantitative detection of D-Dimer,which is high sensitivity?strong specificity?good precision?excellent stability and linear range is wide.To provide a new technique and method for detecting D-Dimer in clinical. To provide more convenient and practical value for clinical to diagnosis corresponding diseases. MethodsIn this study,we prepared colloidal gold solution by making citric acid three sodium restore chloroauric acid.Cracking fibrin by using urokinase,we prepared the internal quality controls of D-Dimer.We optimized and selected the technological conditions and experimental conditions by applying perfect test technology and platform of colloidal gold immunochromatography in Henan Biological Engineering Technology Research Center.We evaluated the sensitivity, specificity, linearity, precision and stability of the test paper.The test method established in this study was compared with the ACL-TOP700 detecting system(immunoturbidimetry, ITM) of American IL company.The correlation between the two results was compared. ResultsIt showed that the stability of the internal quality controls of D-Dimer produced in this study have meet national requirements of indoor quality controls.They can be stored 7 months at least at-20?,3 months at least at 4?,7 days at least at 37?.The minimum detective limit of the quantitative detection method of the colloidal gold immunochromatography for D-Dimer established in this study is 0.15625ug/ml,and the linear range is 0.15625-10ug/ml.There was no cross reactivity with fibrinogen, triglyceride and bilirubin.Intra batch precision test and inter batch precision test were carried out by using 1.25ug/ml and 5ug/ml reference materials.The intra variation coefficients was 3.78% and 2.81% respectively,and the inter variation coefficients was 4.95% and 4.07% respectively.Up to now,no decline has been founded in the performances of the test strips produced in our study after being stored for 12 months at 4~25 and being stored for 144 h at 37? ?.We detected the concentration of D-Dimer in 55 clinical samples by using the detection method established in this study,which have been determined out definite value by the ACL-TOP700 test system(immunoturbidimetry,ITM) of American IL company. The correlation coefficient between this result and IL company's result was R2=0.98593,and the regression equation was Y=0.95964X+0.02645.The correlation between them is good.These statistics and results proved that The basic properties of the quantitative detection method of the colloidal gold immunochromatography for D-Dimer established in this study have meet the clinical requirements basically. Conclusions(1)Stable D-Dimer indoor references were successfully obtained,which can be used to establish the quantitative detection method of colloidal gold immunochromatography for D-Dimer successfully;(2)We successfully established the standard curve of the quantitative detection method of the colloidal gold immunochromatography for D-Dimer in this study;(3)We have initially and successfully established the quantitative detection method of colloidal gold immunochromatography for D-Dimer.