lilunshang，renhefenxifangfadouyouyidingdewucha
，qiebutongfenxifangfawuchacunzaijiaodadechayi。zaihuaxuefenxizhong
，tongchangdebiaozhunfangfaduizhunqueduyouyidingdeyaoqiu
，yunxudewuchayeshixiangduide。youdejiancexiangmu，youyufenxifangfabenshencunzaiyidingdejuxianxing
，erzaochengjiabiaohuishoulvzhipiandihuopiangao。

如：caiyongmafulugaowenhuihuachuliyangpin，yixierongyihuifadeyuansucedinghuishoulvpiandideyuanyinzhengshiyouyugaowenshidaiceyuansuhuifasunshiyinqide。yinci，tongguocedinghuishoulvdejieguo
，kezaiyidingchengdushangzhengmingfangfadezhunquexing。

zaihuaxuefenxizhong，youyudaicewuzhidoushizaiyidingdenongdufanweineicaijuyoumougetedingdezhunquedu，chaochugaifanwei，kenenghuichanshengjiaodadewucha。zaizuojiabiaohuishoushi，dangyangpinzhongdaicewuhanliangjiaodishi。jiarubiaozhunwuzhitaishao

，cedehuishoulvwuchajiaoda；加(jia)入(ru)標(biao)準(zhun)物(wu)質(zhi)太(tai)多(duo)，則(ze)會(hui)改(gai)變(bian)待(dai)測(ce)物(wu)質(zhi)在(zai)加(jia)標(biao)樣(yang)品(pin)和(he)樣(yang)品(pin)中(zhong)的(de)測(ce)定(ding)背(bei)景(jing)，也(ye)可(ke)能(neng)會(hui)產(chan)生(sheng)較(jiao)大(da)的(de)誤(wu)差(cha)。因(yin)此(ci)在(zai)進(jin)行(xing)加(jia)標(biao)回(hui)收(shou)時(shi)，加(jia)標(biao)量(liang)的(de)水(shui)平(ping)要(yao)適(shi)當(dang)，太(tai)高(gao)或(huo)太(tai)低(di)都(dou)不(bu)會(hui)得(de)到(dao)預(yu)期(qi)的(de)效(xiao)果(guo)，通(tong)常(chang)應(ying)注(zhu)意(yi)以(yi)下(xia)兩(liang)點(dian)。

一是標準加入的量要明顯高於檢出限
，二是要盡量與分析組分的含量一致，但同時考慮又不能超出方法檢測的容許範圍。

例如：在zai分fen光guang光guang度du分fen析xi中zhong，當dang樣yang品pin中zhong待dai測ce物wu含han量liang較jiao高gao時shi
，加jia入ru標biao準zhun物wu質zhi過guo高gao，使shi加jia標biao後hou測ce定ding值zhi接jie近jin方fang法fa的de檢jian出chu上shang限xian，這zhe樣yang測ce得de加jia標biao樣yang中zhong待dai測ce物wu的de誤wu差cha較jiao大da

，加jia標biao後hou引yin起qi的de濃nong度du增zeng量liang在zai方fang法fa測ce定ding上shang限xian濃nong度duc的0.4~0.6倍之間為宜。

通tong常chang情qing況kuang下xia，盡jin管guan因yin加jia標biao而er增zeng大da了le試shi樣yang體ti積ji，樣yang品pin分fen析xi過guo程cheng中zhong有you蒸zheng發fa或huo消xiao解jie等deng可ke使shi溶rong液ye體ti積ji縮suo小xiao的de操cao作zuo技ji術shu時shi，樣yang品pin經jing處chu理li後hou重zhong新xin定ding容rong並bing不bu會hui對dui分fen析xi結jie果guo產chan生sheng影ying響xiang。但dan加jia標biao體ti積ji過guo大da，容rong易yi因yin加jia入ru過guo多duo溶rong劑ji影ying響xiang檢jian測ce結jie果guo。

如：zaicaiyongnongsuanxiaojieyangpinshi。guoduojiarushuirongye。shisuannongdutaidi，kenengyingxiangyangpinxiaoguo。dangjiarubiaozhunwuzhishiyoujirongjishi，jiabiaoliangguoduo，zehuizaochengrongjihebiaozhunwuzhinanyizaishuizhongrongjie
，congeryinrongjieduwentizaochengduijiabiaohuishoulvdeyingxiang。

youyujiabiaohuishoulvshiyanxuyaocaozuorenyuanjingguoyixiliecaozuobuzhouwancheng

，chulejiabiaodebuzhouwai

，qitarenheyuyangpinjianceyouguandecaozuobuzhoudoukenengyingxiangjiabiaoyangpinheyuanyangpinzhongdaicezufendejieguo，suoyi
，zhexiecaozuorenyuandeshuipingjunzhijieyingxianghuishoulvdejieguo。

通常情況下，樣品待測組分本底值（原含量）不能過大。樣品本底值太大
，加標量無法與之匹配，回收量的相對誤差就大
，回收率偏差即大；反之回收率偏差即小。因此
，在低濃度區加標回收率要受樣品中本底值的影響更為明顯。