Development And Verification Of An Automatic Fluorescence Quantitative Analyzer For Fluorescence Latex-based Immunochromatography Assay

POCT(point-of-care testing),refers to the clinical examination beside the patient.It is a new method for immediate analysing at the sampling site,eliminating the complex procedures of specimens processing in laboratory,and quickly obtaining results.It has various advantages,such as convenient,fast,efficient and low cost.At present,POCT has become a new subdivision industry in IVD(In Vitro Diagnostics),which is going to play a key role in the worldwide diagnosis market.Most of the first generation POCT products currently on the market need to be manually operated.The disadvantage of these products are lack of high throughput,intelligence and automatics.These limitations,on the one hand,cause huge manpower costs and reduce the efficiency of the testing;on the other hand,it brings various risks to the accuracy of the test results.Therefore,it is necessary to have a new product that can meet the special needs in China and also keep the characteristics of POCT.Based on the above two core requirements,a full automatic fluorescence immunochromatography analyzer is developed.The propsoed automatic fluorescence quantitative immunochromatography analyzer with special reagents(fluorescent quantitative immunochromatography)is used to detect the concentration of specific biomarkers in human samples which are mainly blood and urine,thus assisting the diagnosis of disease.The hardware structure of the developed analyzer consists of a test tube device,a shaking device,a sampling device,a mixing device,a buffer device,a cleaning device,a reagent card device,a incubating device,a measuring device,and a system control module.In view of the characteristics of many hardware modules of the analyzer,a small distributed control system is constructed to achieve high efficient motion control and data acquisition in a small amount of communication process for a large number of state information.The designed instrument can automatically complete the sorting,mixing and sampling from the sample,adding the buffer liquid cup to the material automatically,adding the sample dilution and mixing,then adding the reagent card to the material automatically,adding the mixed liquid,sorting the temperature control reaction,and finally automatically scanning the fluorescence signal for the full inspection process,realizing the ”unattended” set.Sample sorting,operation processing.The analyzer uses automation technology.The instrument can independently process all procedures include ordering,mixing and picking of samples,buffer feeding,sample dilution,reagent feeding,mixture injection,reaction temperature controlling,on-processing reagent ordering and fluorescence signal scanning and detecting.The developed equipment combines the original scanning fluorescence detection technology and automatic motion control technology,and develops a small desktop fully automatic POCT analyzer that can achieve ”unattended operation” in all procedures include sample ordering,operating,scanning and detecting.Experiments were conducted for testing the repeatability,stability,precision of fluid transfer,accuracy of fluid transfer,linear correlation,accuracy of clinical detection and carrying pollution rate of the developed analyzer.Comparisons with the existing manual operation immunochromatography analyzer were also conducted.The results show that the automatic fluorescence immunochromatography analyzer has the advantages of better reproducibility,sustainable and stable operation,and effective avoidance of artificial fatigue when compared with the manual operated immunochromatography analyzer.For example,when the C reactive protein with the lowest concentration of 1mg/L was detected,the measured variation coefficient of the designed analyzer was 9.45%,while the coefficient of variation of the control instrument was 10.71%.In addition,the clinical comparison test showed that when the same detection reagent was used,the correlation between the test results of the experimental instrument and the detection results of the biological VIDAS was 0.9859,while the correlation between the control instrument and the biological VIDAS test results was0.9571,indicating that the test results of the fully automatic instrument were in accordance with the clinical requirements.It is slightly better than the result of standardized manual operation,and has a certain effect on the performance of reagent detection.