1、单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,生化测量系统的校准,南通大学附属医院,王惠民,一、与校准相关的一些基本问题,校准(,Calibration,)重要吗?,实验室中测量不合格约,15%,由校准误差所致,临床医生往往认为检验结果的“不准”是由不正确的校准造成的,陈文祥主任认为,检验结果互认的前提是:,测量结果是否具有可比性,(溯源,方法性能评价:校准),可比性的标准,参考测量区间,(一致化问题),校准受到重视了吗?,一般由组长进行校准,一般无,SOP,,或,SOP,不够详细,CLSI,或去其他的国际组织尚未有相应的标准或指南,一般的实验
2、室无校准的记录,科主任一般不过问校准的正确与否,校准什么?,测量仪器?测量系统(“调标”或“定标”)?,测量仪器:单独或与辅助设备组合,用于测量的装置。,测量系统:由一台或多台测量仪器所组成的用于,特定测量的成套系统,包括试剂和电源等。,校准实际上就是将测量系统与“参考系统”进行比较,并将测量系统调整至参考系统相一致水平的过程。,实际上,有些情况下不需要对测量系统进行校准,临床化学测量常根据系数进行计算,例:酶催化活性浓度的测量,F,值又称为,K,值,项目,理论,K,值,校准,K,值,校准,K,值与理论,K,值之间的误差,RANDOX,试剂,国产试剂,RANDOX,试剂,国产试剂,ALT,-3
3、633,-4201,-5079,-15.63%,-39.80%,AST,-3633,-4211,-5020,-15.91%,-38.18%,ALP,3262,3966,4090,-21.58%,-25.38%,GGT,4964,5059,5286,-1.91%,-6.49%,CK,7106,6236,5734,12.24%,19.31%,LDH,7106,10254,13785,-44.30%,-93.99%,校准,K,值与理论,K,值的比较,DiaSys,Randox,为什么用校准品后得到的,K,值与理论,K,值不一致?,校准品是如何定值的?,方法不一样,(参考方法),仪器不一样,(最好的仪
4、器,每次定值前都必须对仪器进行校准),试剂不一样,(最好的试剂),参考方法与常规方法测量仪器的差异,参考方法,(,Agilent Cary 4000,),常规方法,(,JJG464-2005,要求),波长准确度,0.1nm,5nm,波长精密度,0.025nm,2.5nm,吸光度准确度,0.00025A,0.07A,温度准确度,37,0.1,37.00.1,半波宽,0.05nm,15nm,二、校准前的准备,1.,生化分析仪的准备,生化分析仪的校准或检定,生化分析仪的性能验证,2.,试剂的准备,试剂是否获准入,试剂的性能验证,3.,水的准备,1.,生化分析仪的准备,生化分析仪的校准或检定,由厂家根
5、据其标准对生化分析仪进行校准,由有关计量部门根据国家标准(,JJG494-2005,)对仪器进行检定,生化分析仪的性能验证(根据中华人民共和国生化分析仪检定规程,JJG 494-2005,进行),零点漂移,波长准正确度及重复性,杂散光,吸光度正确度,吸光度重复性,吸光度线性误差,交叉污染率,温度正确度,比色杯间差距,生化分析仪检定用标准物质,用于吸光度,正,确度与重复性检定的标准物质,杂散光检定的标准物质,吸光度线性检定的标准物质,交叉污染检定的标准物质,中国计量科学研究院,北京市北三环东路,18,号,电话:,010-64524710,,,64278838,零点漂移,开机,30min,用蒸馏水
6、调吸光度至,0.000,处,,10min,内吸光度的最大变化值应符合下表规定:,类,级,飘移值,一,(棱镜式或,光栅式,),A,0.002,B,0.004,C,0.006,二,(干涉滤光片或吸收滤光片),A,0.002,B,0.004,C,0.006,单波长,(nm),飘移(,A,),双波长,(nm),飘移(,A,),340,0.0148,340/405,0.0015,405,0.0093,405/570,0.0009,450,-0.0060,450/600,0.0004,505,0.0088,505/660,0.0006,660,0.0036,660/750,-0.0004,复兴仪器的零点飘
7、移,复兴仪器,340nm,零点漂移,复兴仪器,340nm,零点漂移,复兴仪器,405nm,零点漂移,复兴仪器,405nm,零点漂移,复兴仪器,340/405nm,零点漂移,复兴仪器,340/405nm,零点漂移,复兴仪器,405/505nm,零点漂移,出现零点飘移可能原因,电压不稳,光电倍增管或光接收元件老化,仪器灵敏度过高,仪器设计与制造的缺陷,波长的正确度,波长正确度的测定方法根据分光原理不同而异,分光式仪器(光栅由于不需传动调节波长,一般不需校准),低压汞灯、氘灯、干涉滤光片,镨钕滤光片、氧化钬滤光片,滤光式仪器 将滤光片拆下在已校准的分光光度计上进行波长扫描,测定波长和半波宽,一般仪器
8、不容易拆卸,特征谱线,低压汞灯,:253.7nm,氘灯,:486nm,、,656.1nm,镨钕滤光片,:529nm,、,808nm,(,400nm,900nm,内至少有,10,个吸收峰),氧化钬滤光片,:200,700nm,共,12,条谱线,干涉滤光片,:,长波通滤光片,:200,1100nm,,光学分辨率为,1nm,短波通滤光片,:400,700nm,,光学分辨率为,1nm,波长的重复性,指多次波长测试数据的离散性,或者多次波长测试数据的符合程度。,一般取波长正确度的,3,次测试结果中最大值与最小值之差作为波长重复性。,波长正确度及重复性的要求,(,nm,),类,级,波长范围,正确度,重复性
9、一(分光类仪器),A,340,700,1,0.5,B,340,700,3,1.5,C,340,700,5,2.5,类,级,波长范围,正确度,半波宽,二(滤光类仪器),A,340,700,2,10,B,340,700,4,12,C,340,700,6,15,杂散光,杂散光与波长的半波宽有关,半波宽越大,杂散光越多。,测定,50g/L,亚硝酸钠(,NaNO,2,)标准溶液相对于蒸馏水在,340nm,处的吸光度,了解杂散光的多少。,亚硝酸钠溶液的配制方法,将分析纯亚硝酸钠固体试剂放入称量瓶置于烘箱中,在箱温为,1055,下烘,2h,,取出置于干燥器中冷却至室温,在分析天平上(精度为,0.1mg,)
10、精确称取,10g,,置于,200mL,烧杯中,用小半杯蒸馏水溶解后移入,200mL,容量瓶中,以少量蒸馏水冲洗烧杯三次,均倒入容量瓶中,然后用蒸馏水稀释至刻度线反复摇匀,置于阴凉干燥处备用。,340nm,340nm,340nm,345nm,345nm,杂散光,1,)在波长,340nm,,第一个试剂位放入蒸馏水,以蒸馏水为样本,重复测定,5,次吸光度值;第二个试剂位放入,NaNO,2,溶液,以,NaNO,2,溶液为样本,重复测定,5,次吸光度值;或将蒸馏水和,NaNO,2,溶液分别加入同一比色杯读取吸光度(可消除比色杯误差),重复测定,5,次,共得,5,个蒸馏水和,5,个,NaNO,2,溶液的吸
11、光度。,2,)最小,NaNO,2,溶液吸光度,-,最大蒸馏水吸光度,2.3,。,复兴仪器的杂散光测定,复兴仪器的杂散光测定,复兴仪器的杂散光测定(空白),吸光度正确度,指吸光度实际测定值与理论值之差,该偏差越小吸光度正确度越高,间接说明波长的正确度与杂散光的多少。,1,)国家标准物质法,2,)己糖激酶法,吸光度正确度,1,)国家标准物质法:,使用国家标准物质研究中心制备的标准物质溶液,其吸光度分别为,0.5,和,1.0,。,在,340nm,波长、比色杯光径,1cm,时,以标准物质标示的参比液作参比,测吸光度值,重复测量,3,次。,计算,3,次测量值的算术平均值与标准值之差,,0.5,的标准液允
12、许误差为,0.025,,,1.0,的标准液,允许误差为,0.07,。,测定结果,标准物质的吸光度:,A,1-1,=0.489 A,1-2,=0.980,(不确定度:,0.005,),检测结果:,A,1-1,=0.4916,;,0.4836,;,0.4812,,均值为,0.4855,A,1-2,=0.9703,;,0.9714,;,0.9722,,均值为,0.9713,结果判定:,A,1-1,误差,0.025,;,A,1-2,误差,0.07,。即,0.464A,1-1,0.514,;,0.910A,1-2,1.050,吸光度正确度,2,)己糖激酶法,用己糖激酶(,HK,)法测定葡萄糖浓度时,反应
13、产生,NADH,,在,340nm,测定吸光度,间接测,NADH,的,(,理论值为,6220,),以此为标准校正,。,以,HK,测葡萄糖为例,试剂反应过程如下:,HK,葡萄糖,+ATP-6-P-,葡萄糖,+ADP,G6PDH,6-P-,葡萄糖,+NAD,+,-,葡萄糖酸,+NADH,影响吸光度准确度的主要因素,杂散光多,波长不正确,标准液不正确,仪器的灵敏度或其他原因,吸光度重复性,1,)以重铬酸钾标准溶液为样本,在波长,340nm,,吸光度为,0.3,0.5,以蒸馏水为空白,试剂量为全自动生化分析仪标称的最小试剂量、测定时间为,10min,;每,30,秒读取吸光度,连续,20,次,得到,20,
14、个吸光度值。,计算,CV,,应,1.0%,2,),采用吸光度约为,0.5,生化分析仪用吸光度标准物质,在,340nm,处连续测定,5,次,然后计算其中最大值与最小值之差。吸光度的重复性均应不大于,0.005,检测结果:,A1-1=0.4828,;,0.4831,;,0.4836,;,0.4812,;,0.482,0.4836-0.4812=0.00240.005,吸光度线性误差,分别用浓度为,2.0,、,4.0,、,6.0,、,8.0,、,10.0g/L,的氯化钴标准溶液,以蒸馏水为对照,在,510nm,(,500-520nm,)测定各溶液吸光度,连续测量,3,次,然后将所得数据求相关系数,,
15、r,0.995,。或按下列公式计算,线性误差符合规定要求。,分光装置,吸光度范围,线性误差(,%,),棱镜或光栅,0.1-0.3,5,0.3-0.6,4,0.6-0.9,5,结论:符合吸光度线性要求,交叉污染率,概念:由测量系统将一个检测样品反应携带到另一个检测样品反应的分析物不连续量,由此错误地影响了另一个检测样品的表现量。,1,、氯化钴方法,2,、桔红,G,方法,3,、临床标本的检测:,50U/L,与,250U/L,的,AST,或,ALT,测定,测定方法:,将氯化钴标准溶液按仪器规定的最小样品量,先用质量浓度为,2.0g/L,的氯化钴标准溶液将比色杯冲洗三次,接着对该溶液连续测量四次。按上
16、述方法依次循环对,2.0,和,10.0g/L,氯化钴标准溶液重复测得七组在,510nm,处的测量值(四组低浓度值和三组高浓度值),然后按以下公式将每相邻两组值进行计算,得到三个低浓度到高浓度的计算值和三个高浓度到低浓度的计算值,即为交叉污染率,均应,1.5%,。,L,1,=0.1634,;,L,2,=0.1691,;,L,3,=0.1639,;,L,4,=0.1668,H,1,=0.8316,;,H,2,=0.8331,;,H,3,=0.8305,Co,LH,=(0.8317-0.8316)/(0.8317-0.1666)100%=0%,Co,HL,=(0.1634-0.1666)/(0.83
17、17-0.1666)100%=-0.4%,结论:交叉污染率符合要求,温度正确度,用分度值小于,0.1,专用测温装置,测定比色杯的设定温度,当仪器升到设定温度范围内,每隔,30s,记录一次温度,连续测,10,次,计算平均值。,Fluke 1521,点温度计(,0,.,001C,)。,类,级,温度准确度,一、二,A,0.1,B,0.3,C,0.5,1,37.182,0.182,9,37.079,0.079,21,37.069,0.069,29,37.112,0.112,41,37.069,0.069,49,37.035,0.035,61,36.993,-0.007,69,37.028,0.028,
18、81,37.020,0.020,89,37.069,0.069,101,37.088,0.088,119,37.053,0.053,121,37.095,0.095,129,37.125,0.125,141,36.977,-0.023,149,37.062,0.062,151,36.811,-0.089,159,37.045,0.045,杯号,温度,温度差,杯号,温度,温度差,极差,0.205,比色杯间差距,以重铬酸钾标准溶液为样本,在波长,340nm,,吸光度为,0.3,0.5,以蒸馏水为空白,每比色杯重复测定,3,次,平均吸光度值应小于,0.05,(,Olympus),。,杯号,A,杯号,
19、A,杯号,A,杯号,A,1,0.403,11,0.4011,21,0.4016,31,0.4043,2,0.4018,12,0.4047,22,0.4093,32,0.4031,3,0.4033,13,0.4105,23,0.4043,33,0.4112,4,0.4047,14,0.405,24,0.4076,34,0.4043,5,0.4088,15,0.4054,25,0.4111,35,0.4154,6,0.4089,16,0.4049,26,0.3964,36,0.407,7,0.4126,17,0.4058,27,0.4041,37,0.4093,8,0.4023,18,0.4023
20、28,0.4053,38,0.4081,9,0.4052,19,0.4112,29,0.4073,39,0.408,10,0.4023,20,0.4091,30,0.402,40,0.4146,杯号,A,杯号,A,杯号,A,杯号,A,41,0.4173,51,0.4184,61,0.4003,71,0.4052,42,0.4142,52,0.4201,62,0.4037,72,0.4053,43,0.4147,53,0.4188,63,0.4062,73,0.3989,44,0.4134,54,0.4092,64,0.4038,74,0.4043,45,0.4213,55,0.4034,65
21、0.4045,75,0.3989,46,0.4066,56,0.4025,66,0.403,76,0.4011,47,0.4025,57,0.4136,67,0.3981,77,0.4042,48,0.4115,58,0.4083,68,0.4019,78,0.4052,49,0.4192,59,0.4116,69,0.4037,79,0.4031,50,0.4132,60,0.4031,70,0.4046,80,0.3979,杯号,A,杯号,A,杯号,A,杯号,A,81,0.4014,91,0.4043,101,0.4027,111,0.4077,82,0.4078,92,0.4027,1
22、02,0.4049,112,0.4029,83,0.4022,93,0.4038,103,0.4014,113,0.403,84,0.4077,94,0.4025,104,0.4041,114,0.3996,85,0.4041,95,0.4043,105,0.3992,115,0.4023,86,0.4014,96,0.4033,106,0.4023,116,0.4026,87,0.4093,97,0.3998,107,0.4062,117,0.4025,88,0.4049,98,0.4023,108,0.4039,118,0.4008,89,0.4016,99,0.4041,109,0.40
23、5,119,0.4027,90,0.4072,100,0.402,110,0.405,120,0.3958,杯号,A,杯号,A,杯号,A,杯号,A,121,0.4097,131,0.4003,141,0.4023,151,0.403,122,0.4012,132,0.4043,142,0.4058,152,0.4035,123,0.4033,133,0.4064,143,0.4054,153,0.4045,124,0.4064,134,0.403,144,0.4031,154,0.4047,125,0.403,135,0.4018,145,0.4012,155,0.4101,126,0.403
24、9,136,0.4039,146,0.3979,156,0.403,127,0.3995,137,0.4003,147,0.3994,157,0.4031,128,0.4166,138,0.4006,148,0.4154,158,0.4014,129,0.402,139,0.4026,149,0.4124,159,0.4049,130,0.4004,140,0.4041,150,0.4012,160,0.4116,极差,=0.4213-0.3958=0.0255,2.,试剂的准备,试剂是否获准入,是否有,SFDA,证书,试剂的性能验证,精密度,线性,延迟时间(如果有),空白对照,3.,水的准备
25、用一级水,三、校准过程中需注意的问题,校准品,:,是否可溯源?配套?互换性?,处理,:,低温冷冻、冻干品?(复溶条件?瓶间差问题?),测几个水平校准品:不同水平校准品,K,值是否一致?,校准品测量次数:对校准,K,值的影响?取平均,K,值?,空白测量:对校准,K,值的影响?,校准周期:对校准,K,值的影响?,校准的核查:是否有核查程序?,英国,RANDOX,公司“人基质复合校准血清”,以人血清为基质,根据德国临床化学协会的规定赋值,由全球,3000,多家参考实验室赋值,每种仪器至少由,10,家实验室赋值,复溶条件,:20,25,30,分钟,对,CO,2,、,ACP,与,ALP,有特殊要求,未
26、提供不确定度,所有测量系统的值均一样,德国,DiaSys,公司“人基质复合校准血清”,TruLab,N,、,TruLab,P,和,TruCal,U,以人血清为基质,根据德国临床化学协会的规定赋值,复溶条件,:,25,30,分钟(,ALP 2,小时),美国,Roche,公司,C.f.a.s,(Calibrator for automated systems),适用于,Roche,系统的,Roche,方法,在人基质血清中加入了人及各种动物来源的组份,加入稳定剂,在,Roche,规定的严格的条件下,由,Roche,的主校准品赋值,复溶条件,:20,25,30,分钟,美国,Beckman,公司,(,S
27、ynchon,Multi Calibrator),适用于,Synchon,试剂,加入稳定剂,溯源至,NIST,液态,不需复溶,美国,Bio-Rad,公司控制品,以人血清基质,可任选液体,/,干粉、定值,/,不定值产品,液体不含甘油和乙二醇,提供任何仪器,/,试剂的定值,多个品种、包装、浓度可供选择,美国,FDA,认证,某国产检测系统(,X,)分别与罗氏,C.fas,校准品,(Y1),、与朗道,Level2,校准品,(Y2),、与朗道,Level3,校准品,(Y3),比较,三、校准过程中需注意的问题,校准品,:,是否可溯源?配套?互换性?,处理,:,低温冷冻、冻干品?(复溶条件?瓶间差问题?加溶
28、剂的准确性),测几个水平校准品:不同水平校准品,K,值是否一致?,校准品测量次数:对校准,K,值的影响?取平均,K,值?,空白测量:对校准,K,值的影响?,校准周期:对校准,K,值的影响?,校准的核查:是否有核查程序?,CK,校准,测定,天数,s1ABs,K,K,*,1,3,56858,57132,57506,57282,2,3,58163,59694,59643,59387,3,3,53774,54057,53916,53632,4,4,54157,55178,54608,54371,56367,s,2354,4.2%,室温复溶条件下校准,CK,CK,校准,测定,天数,s1ABs,K,K,*
29、1,4,55474,55717,55961,56107,2,4,55474,55742,55255,55255,3,3,55746,56797,56577,56015,4,3,55474,55596,55182,55060,55772,s,550,1.0%,标准化复溶条件下校准,CK,(置于,18,20,水温下复溶,305min,),校准品处理的注意点,必须将复溶条件标准化。虽不会对所有被测物产生影响,但对,CK,、脂蛋白会产生较大影响。应有严格,SOP,。,加样的重复性,(,0.4%,),是否有瓶间差,值得研究,(,0.5%,),注意排除离群值。,严格控制校准条件,将,K,值,CV,控制在
30、1%,内,。,(制定校准的标准),LDH,校准,测定,天数,s1Abs,K,K*,1,2,89035,90088,90746,90482,2,1,88646,88864,88995,89126,3,2,89035,90307,90088,89956,4,2,88646,88166,86331,88078,89536,s,930,1.0%,标准化复溶条件下校准,LDH,差,.6%,三、校准过程中需注意的问题,校准品,:,是否可溯源?配套?互换性?,处理,:,低温冷冻、冻干品?(复溶条件?瓶间差问题?),测几个水平校准品:不同水平校准品,K,值是否一致?,校准品测量次数:对校准,K,值的影响?取
31、平均,K,值?,空白测量:对校准,K,值的影响?,校准周期:对校准,K,值的影响?,校准的核查:是否有核查程序?,在,ISO 11095:1996,基于标准样品的线性校准,(,GB/T 22554-2010,)中确定,对于基本校准方法的最少校准点,/,水平是,3,个。,EURACHEM“,分析方法的目标适用性,”指南规定:对于校准,包括空白至少,6,个浓度水平。,Commission Decision 2002/657/EC,规定:建立一个校准曲线,包括零浓度至少需要,5,个浓度水平。,ISO 11095:1996,认为校准系统的有效性检查,至少有,2,个、最好是,3,个校准水平通过控制图监控
32、校准的有效性。,三、校准过程中需注意的问题,校准品,:,是否可溯源?配套?互换性?,处理,:,低温冷冻、冻干品?(复溶条件?瓶间差问题?),测几个水平校准品:不同水平校准品,K,值是否一致?,校准品测量次数:对校准,K,值的影响?取平均,K,值?,空白测量:对校准,K,值的影响?,校准周期:对校准,K,值的影响?,校准的核查:是否有核查程序?,LDH,校准,测定,天数,s1Abs,K,K*,1,2,89035,90088,90746,90482,2,1,88646,88864,88995,89126,3,2,89035,90307,90088,89956,4,2,88646,88166,863
33、31,88078,89536,s,930,1.0%,标准化复溶条件下校准,LDH,差,.6%,ISO 11095:1996,要求每个校准水平至少重复,2,次,并建议尽可能多次。,和校准水平的数量一样,随着重复分析次数的增加,收益可能递减。因此,每个校准水平重复分析超过,5,次不能提供大的额外好处。,三、校准过程中需注意的问题,校准品,:,是否可溯源?配套?互换性?,处理,:,低温冷冻、冻干品?(复溶条件?瓶间差问题?),测几个水平校准品:不同水平校准品,K,值是否一致?,校准品测量次数:对校准,K,值的影响?取平均,K,值?,空白测量:对校准,K,值的影响?,校准周期:对校准,K,值的影响?,
34、校准的核查:是否有核查程序?,三、校准过程中常遇到的问题,校准品,:,是否可溯源?配套?互换性?,处理,:,低温冷冻、冻干品?(复溶条件?瓶间差问题?),测几个水平校准品:不同水平校准品,K,值是否一致?,校准品测量次数:对校准,K,值的影响?取平均,K,值?,空白测量:对校准,K,值的影响?,校准周期:对校准,K,值的影响?,校准的核查:是否有核查程序?,相对偏倚小于,1/3 CL IA88,三、校准过程中需注意的问题,校准品,:,是否可溯源?配套?互换性?,处理,:,低温冷冻、冻干品?(复溶条件?瓶间差问题?),测几个水平校准品:不同水平校准品,K,值是否一致?,校准品测量次数:对校准,K
35、值的影响?取平均,K,值?,空白测量:对校准,K,值的影响?,校准周期:对校准,K,值的影响?,校准的核查:是否有核查程序?,1,、用另一校准品或另一水平的校准品进行验证,2,、正确度验证,卫生部临检中心正确度验证计划(小分子代谢物、脂类、酶、,GHB,、血细胞),与参考测量程序比较、与公认的方法比较,与参考物质比较,与,EQA,靶值比较,回收实验,四、校准过程需注意的其他问题,人员因素,科领导是否对校准重视,有无制定校准,SOP,制定的校准,SOP,太简单,甚至有错误;,只有校准,SOP,,无记录或审核要求;,无校准出问题的纠正措施文件和记录,以及评审与改正的措施;,能否严格要求技术人员执行,SOP,。,制定“校准”的,SOP,卫生部标委会将制定临床实验室用于校准的标准,(目前尚未见用于临床化学的校准的标准,如,CLSI,),实验室主任应保证校准工作按规范进行,所有的校准工作都必须有记录和分析,Thank you!,






