Introduction on protein value-transfer procedure using cystatin C as an example

doi:10.3969/j.issn.1673-8640.2016.12.016

Abstract

Abstract:

Objective To introduce protein value-transfer principle and procedure by immunoassay using cystatin C（Cys C） national standard as an example.Methods In open system of particle-enhanced turbidimetry immunoassay（PETIA）,ERM-DA471 dilutions were used as calibrators,and candidate national standard dilutions were used as samples. Whereas,in closed system of particle-enhanced nephelometry immunoassay（PENIA）,the manufacturer's calibrators must be used,and the dilutions of ERM-DA471 and candidate national standard were both determined as samples. All reconstitutions and dilutions were controlled by weighing. Based on mathematical principles,the national standard concentration was deduced from the slope of regression line passing through the zero obtained by plotting testing results against theory dilutions. Results The concentrations for Cys C in candidate national standards were 4.41 mg/L and 4.52 mg/L by PETIA and PENIA,and the coefficients of variation（CV） were 1.3% and 1.5%,correspondingly. Conclusions This procedure is expected to improve the protein value-transfer reliability by weighing dilutions and multipoint fitting.

Key words: Cystatin C, Value-Transferation, Turbidimetry immunoassay, Protein

CLC Number:

R446.1

KANG Juan. Introduction on protein value-transfer procedure using cystatin C as an example[J]. Laboratory Medicine, 2016, 31(12): 1081-1086.

Figures/Tables 8

References 17

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项目	R₁	R₂	R₃^*	R₄^*	R₅^*	R₆^*
ERM-DA471（g）	0.200 0	0.500 0	0.390 0（R₂）	0.300 0（R₃）	0.200 0（R₄）	0.100 0（R₅）
稀释缓冲液（g）	0.000 0	0.125 0	0.130 0	0.150 0	0.200 0	0.100 0
稀释因子	1.000 0	0.800 0	0.750 0	0.666 7	0.500 0	0.500 0
预稀释因子	1.000 0	1.000 0	0.800 0	0.600 0	0.400 0	0.200 0
理论相对浓度（%）	100.00	80.00	60.00	40.00	20.00	10.00

项目	R₁	R₂	R₃^*	R₄^*	R₅^*	R₆^*
ERM-DA471（g）	0.200 0	0.500 0	0.390 0（R₂）	0.300 0（R₃）	0.200 0（R₄）	0.100 0（R₅）
稀释缓冲液（g）	0.000 0	0.125 0	0.130 0	0.150 0	0.200 0	0.100 0
稀释因子	1.000 0	0.800 0	0.750 0	0.666 7	0.500 0	0.500 0
预稀释因子	1.000 0	1.000 0	0.800 0	0.600 0	0.400 0	0.200 0
理论相对浓度（%）	100.00	80.00	60.00	40.00	20.00	10.00

项目	T₁	T₂	T₃^*	T₄^*	T₅^*	T₆^*
候选标准物质（g）	0.300 0	0.660 0	0.510 0（T₂）	0.360 0（T₃）	0.240 0（T₄）	0.150 0（T₅）
稀释缓冲液（g）	0.000 0	0.165 0	0.170 0	0.180 0	0.240 0	0.150 0
稀释因子	1.000 0	0.800 0	0.750 0	0.666 7	0.500 0	0.500 0
预稀释因子	1.000 0	1.000 0	0.800 0	0.600 0	0.400 0	0.200 0
理论相对浓度（%）	100.00	80.00	60.00	40.00	20.00	10.00

项目	T₁	T₂	T₃^*	T₄^*	T₅^*	T₆^*
候选标准物质（g）	0.300 0	0.660 0	0.510 0（T₂）	0.360 0（T₃）	0.240 0（T₄）	0.150 0（T₅）
稀释缓冲液（g）	0.000 0	0.165 0	0.170 0	0.180 0	0.240 0	0.150 0
稀释因子	1.000 0	0.800 0	0.750 0	0.666 7	0.500 0	0.500 0
预稀释因子	1.000 0	1.000 0	0.800 0	0.600 0	0.400 0	0.200 0
理论相对浓度（%）	100.00	80.00	60.00	40.00	20.00	10.00

项目	R₁	R₂	R₃^*	R₄^*	R₅^*	R₆^*
ERM-DA471（g）^#	0.200 0	0.517 4	0.389 2（R₂）	0.296 7（R₃）	0.206 8（R₄）	0.101 0（R₅）
稀释缓冲液（g）	0.000 0	0.123 0	0.128 9	0.149 4	0.198 8	0.099 5
稀释因子	1.000 0	0.807 9	0.751 2	0.665 1	0.509 9	0.503 7
预稀释因子	1.000 0	1.000 0	0.807 9	0.606 9	0.403 7	0.205 8
理论相对浓度（%）	100.0	80.79	60.69	40.37	20.58	10.37