In this work, a procedure is proposed for the direct analysis of powdered refreshments by fast sequential flame atomic absorption spectrometry (FS-F AAS), after a simple treatment of the sample. A full 2³ factorial design was applied, and the variables chosen were as follows: acid concentration, acid type, and sonication time. Optimization provided the best conditions considering a mass of powdered refreshment of about 0.18 g diluted to a final volume of 15 mL with 0.5 mol L⁻¹ HCl. The matrix effect was investigated, and external calibration was feasible for the determination of Cd, Co, Cu, Fe, Mg, Mn, Ni, Pb, and Zn. The limit of quantification (LoQ) obtained was between 0.6 (Cd) and 25 mg kg⁻¹ (Pb). The analyte addition and recovery test were applied to evaluate the accuracy, and recovery percentage values ranging from 83.9 to 109.7% were obtained, which is considered adequate for quantitative analysis. Precision was expressed as relative standard deviation (% RSD); it was less than or equal to 5.0% (n = 7) for all analytes. The procedure was applied to 21 samples of powdered refreshment commercialized in Salvador (Brazil) and Buenos Aires (Argentina). The concentration range and average of the analytes in the samples (in mg kg⁻¹) commercialized in Brazil (BZ) and Argentina (AG) were as follows: Co (BZ < 6.4–9.94, average 8.85; AG < 6.4–10.3, average 9.92), Fe (BZ < 6.9–376, average 270; AG < 6.9–32.81, average 29.11), Mg (BZ < 8.9–363, average 140; AG 770–3139, average 1464), Mn (BZ < 3.2–4.88, average 4.24; AG < 6.9), and Zn (BZ < 1.4–1.68, average 1.68; AG < 1.4). The concentrations of Cd, Cu, Ni, and Pb were lower than the LoQ of the proposed analytical method. For refreshment samples commercialized in Buenos Aires (Argentina), high concentrations of Mg were found in their chemical composition, but Mg had been used as anti-caking agent along with the other components.

中文翻译：

---

简单样品处理后，FS-F AAS顺序测定粉状茶点中的Cd，Co，Cu，Fe，Mg，Mn，Ni，Pb和Zn

在这项工作中，在对样品进行简单处理之后，提出了一种通过快速连续火焰原子吸收光谱法（FS-F AAS）直接分析粉状茶点的程序。应用了完整的2 ³因子设计，选择的变量如下：酸浓度，酸类型和超声处理时间。考虑到用0.5 mol L ^-1 HCl稀释至15 mL最终体积的约0.18 g粉末状提神粉的质量，优化提供了最佳条件。研究了基体效应，并且外部校准对于测定Cd，Co，Cu，Fe，Mg，Mn，Ni，Pb和Zn是可行的。获得的定量极限（LoQ）在0.6（Cd）和25 mg kg ^-1之间（铅）。应用分析物添加和回收率测试评估准确性，得出的回收率百分比值介于83.9％至109.7％之间，被认为足以进行定量分析。精度表示为相对标准偏差（％RSD）； 对于所有分析物，该值均小于或等于5.0％（n = 7）。该程序应用于在萨尔瓦多（巴西）和布宜诺斯艾利斯（阿根廷）商业化的21种粉末状茶点样品。样品中分析物的浓度范围和平均值（单位：mg kg ^-1）（巴西（BZ）和阿根廷（AG）商业化）如下：Co（BZ <6.4–9.94，平均8.85; AG <6.4–10.3，平均9.92），Fe（BZ <6.9–376，平均270; AG < 6.9–32.81，平均29.11），Mg（BZ <8.9–363，平均140； AG 770–3139，平均1464），Mn（BZ <3.2–4.88，平均4.24； AG <6.9）和Zn（BZ <1.4 –1.68，平均1.68； AG <1.4）。Cd，Cu，Ni和Pb的浓度低于提出的分析方法的最低定量限。对于在布宜诺斯艾利斯（阿根廷）商业化的茶点样品，在其化学成分中发现了高浓度的Mg，但Mg已与其他成分一起用作抗结块剂。