Rehan I, Khan M Z, Rehan K, Abrar S U, Farooq Z, Sultana S, Saqib N Us, Anwar H
Appl Opt. 2018 Jul 20;57(21):6033-6039. doi: 10.1364/AO.57.006033.
An optimized laser-induced breakdown spectroscopy (LIBS) system was utilized as a robust tool for the detection of high toxic lead (Pb) in often used edible colors available in local markets. Edible colors are extensively used in different food stuffs and sweet dish items. To attain a highly sensitive LIBS system for the determination of trace amounts of toxic Pb in edible colors and to achieve the best detection limit, various parametric dependence studies were performed. The quantitative determinations were accomplished under the condition of local thermodynamic equilibrium in terms of optically thin plasma. Besides toxic Pb, other elements like Ca, Mg, Fe, and Na were also detected in edible colors. To estimate the concentration of toxic lead in edible colors, calibration curves were plotted by preparing standard samples of different lead concentrations in an edible colors matrix. Results of the LIBS technique were compared with the outcomes of the same samples studied using a standard analytical technique of inductively coupled plasma-optical emission spectroscopy to confirm the contemporary LIBS setup. The color samples were found above the safe permissible level due to the mass of toxic lead. Limit of detection of the LIBS setup was found at 0.86+/-0.03 ppm for toxic lead present in edible color samples.
一种优化的激光诱导击穿光谱（LIBS）系统被用作一种强大的工具，用于检测当地市场上常用食用色素中的高毒性铅（Pb）。食用色素广泛用于不同的食品和甜品中。为了获得用于测定食用色素中痕量有毒铅的高灵敏度LIBS系统并实现最佳检测限，进行了各种参数依赖性研究。在光学薄等离子体的局部热力学平衡条件下完成了定量测定。除了有毒的铅之外，在食用色素中还检测到了其他元素，如钙（Ca）、镁（Mg）、铁（Fe）和钠（Na）。为了估算食用色素中有毒铅的浓度，通过在食用色素基质中制备不同铅浓度的标准样品绘制校准曲线。将LIBS技术的结果与使用电感耦合等离子体发射光谱标准分析技术研究的相同样品的结果进行比较，以确认当前的LIBS装置。由于有毒铅的含量，发现这些色素样品高于安全允许水平。发现LIBS装置对食用色素样品中存在的有毒铅的检测限为(0.86\pm0.03) ppm。
