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为了验证激光诱导击穿光谱(LIBS)分析猪肉中重金属铅(Pb)元素的可行性,选取经实验室Pb污染处理的猪肉样品为研究对象,将样品进行烘干、粉碎和压片物理前处理;利用LIBS获取压片样品的光谱信息,并采用原子吸收光谱(AAS)法对样品中Pb元素真实浓度进行检测.结果显示,LIBS能探测出Pb含量大于4.56 mg/kg的干样样品中PbI405.78特征谱线信息,且样品中Pb特征线的LIBS强度与其浓度具有一定的梯度关系,但简单的线性关系不明显.采用一元二次多项式拟合结果表明,对于含量小于10 mg/kg的样品,预测准确度较高且线性分析灵敏度高,而高浓度样品预测准确度则显著降低.说明可能存在某个浓度界限决定采用不同定标模型的预测精度.本工作的研究为猪肉中Pb元素的LIBS分析提供了可行性证明,为进一步的研究提供了思路.“,”It is likely that pork is polluted by heavy metals during feeding pig and logistics of meat.On this circumstance,it is necessary to detect toxic metals in pork especially by green and sustainable method.In this work,the emerging technology,LIBS (laser induced breakdown spectroscopy),was applied to determine Pb in pork.In order to prove the feasibility of LIBS in doing this,pork was polluted by Pb solution in lab.At the same time,the samples were dried,ground and pressed to pellets to eliminate the effect of water and improve the homogeneity of samples.The spectra of pressed pellets were collected at optimized LIBS conditions and the real concentration of Pb was obtained by conventional AAS (atomic absorption spectroscopy).The results demonstrated that LIBS can detect the characteristic line Pb Ⅰ 405.78 when the content of samples was higher than 4.56 μg/g.The relationship between LIBS intensity of line PbI405.78 and content of Pb was gradient,but it was not simple linear.In addition,the predicted accuracy was higher in samples those had lower content than 10 μg/g when quadratic polynomial only with one variable was utilized.Whereas,the linear sensitivity was higher in samples with lower content especially below 10μg/g.This result indicated that it is possible there is some critical content which can decide different quantitative model.Accordingly,the accuracy of predicted content can be improved.This work displayed that LIBS is a feasible method in analyzing heavy metal Pb in pork and it is potential in further work.