Khalil Ahmed Asaad I, Labib Osama A
Appl Opt. 2018 Aug 10;57(23):6729-6741. doi: 10.1364/AO.57.006729.
A fast detection system based on dual-pulsed laser-induced breakdown spectroscopy (DP-LIBS) was successfully developed and optimized for the estimation of micro-toxic element contents in commercial coffee brands to monitor pollution and ensure food safety. A series of 13 various coffee brands were quantitatively analyzed in this study utilizing DP-LIBS and a standard analytical technique like inductively coupled plasma/optical emission spectrometry (ICP-OES). The micro-toxic elements, such as aluminum (Al), lead (Pb), zinc (Zn), and chromium (Cr), that exist in the coffee brands were exactly identified. We prepared standard matrices in a known concentration in the coffee sample to draw the standard calibration curves for each element, as well as by utilizing a tactic based on the intense line emission of the element of interest as a quantitative analysis. The analytical routines were approved under the expectations that the plasma created by the dual-pulsed lasers was in local thermodynamic equilibrium (LTE) and was optically thin. We investigated the influence of different parametric dependence studies to enhance our DP-LIBS detection sensitivity. Furthermore, the precision of our DP-LIBS data for determining the concentration of micro-toxic elements present in coffee samples was validated via the ICP-OES technique. The results achieved by the DP-LIBS technique were in full agreement with the ICP-OES results. In addition, the estimated limit of detection of our DP-LIB spectrometer for Al, Pb, Zn, and Cr were 105.13±07, 90.17±12, 83.58±15, and 68.78±09 μg L, respectively. The suggested protocols demonstrated the excellent benefits of the DP-LIBS for the detection of micro-toxic elements existing in coffee and for checking the purity and quality of food products.
成功开发并优化了一种基于双脉冲激光诱导击穿光谱(DP-LIBS)的快速检测系统,用于估算商业咖啡品牌中的微量有毒元素含量,以监测污染并确保食品安全。本研究利用DP-LIBS和电感耦合等离子体/光发射光谱法(ICP-OES)等标准分析技术,对13个不同的咖啡品牌进行了定量分析。准确鉴定了咖啡品牌中存在的微量有毒元素,如铝(Al)、铅(Pb)、锌(Zn)和铬(Cr)。我们在咖啡样品中制备了已知浓度的标准基质,以绘制每种元素的标准校准曲线,并采用基于感兴趣元素的强线发射的策略进行定量分析。在双脉冲激光产生的等离子体处于局部热力学平衡(LTE)且光学薄的预期下,对分析程序进行了验证。我们研究了不同参数依赖性研究的影响,以提高DP-LIBS的检测灵敏度。此外,通过ICP-OES技术验证了我们的DP-LIBS数据在测定咖啡样品中微量有毒元素浓度方面的精度。DP-LIBS技术获得的结果与ICP-OES结果完全一致。此外,我们的DP-LIB光谱仪对Al、Pb、Zn和Cr的估计检测限分别为105.13±07、90.17±12、83.58±15和68.78±09μg/L。所建议的方案证明了DP-LIBS在检测咖啡中微量有毒元素以及检查食品纯度和质量方面的优异优势。