Colorimetric sensors based on an eco-friendly sensor molecule immobilized into a polymer matrix have broad applications for detecting trace elements. However, their potential for quantitative analysis of these elements remains little explored. Here, we incorporated rutin or quercetin into films based on starch, poly(vinyl alcohol), and glycerol to detect and quantify Cu²⁺ in different matrices. The films were characterized by colorimetric assays, thickness and solubility analyses, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and mechanical assays. Incorporating the flavonoids in the film decreased its solubility, tensile strength, and modulus of elasticity, while increased its cross-sectional surface irregularity. XRD and DSC results also indicated an increase in film crystallinity in the presence of rutin or quercetin. FTIR analyses showed a more effective incorporation of quercetin than rutin in the polymeric matrix, which was confirmed by flavonoid release studies from the film. The film containing quercetin exhibited selectivity in identifying copper in liquid matrices, changing this color from light yellow to dark yellow. An analytical method to quantify Cu²⁺ was developed, presenting a linear response range of 0.20 to 1.20 mg L⁻¹, with detection and quantification limits of 0.060 and 0.20 mg L⁻¹, respectively, very lower than other methods based on polymeric matrices containing natural dyes. The method was successfully applied for Cu²⁺ determination in cachaça and tap water samples, achieving high accuracy (96-104% of recovery) and precision (relative standard deviation < 6.7%). Our findings represent an advancement in the field of sensors based on natural dyes, demonstrating that such sensors can achieve high sensitivity without the need for complex sample preparation methods.

基于固定在聚合物基质中的环保传感器分子的比色传感器在检测微量元素方面具有广泛的应用。然而，它们对这些元素进行定量分析的潜力仍然很少被探索。在这里，我们将芦丁或槲皮素掺入基于淀粉、聚乙烯醇和甘油的薄膜中，以检测和定量不同基质中的 Cu ²⁺。通过比色测定、厚度和溶解度分析、扫描电子显微镜 (SEM)、傅里叶变换红外光谱 (FTIR)、X 射线衍射 (XRD)、差示扫描量热法 (DSC) 和机械测定对薄膜进行表征。在薄膜中加入类黄酮降低了其溶解度、拉伸强度和弹性模量，同时增加了其横截面表面的不规则性。XRD 和 DSC 结果还表明，在芦丁或槲皮素存在下，薄膜结晶度有所增加。FTIR 分析显示，槲皮素比芦丁更有效地融入聚合物基质中，薄膜中类黄酮释放研究证实了这一点。含有槲皮素的薄膜在识别液体基质中的铜时表现出选择性，将颜色从浅黄色变为深黄色。开发了一种定量 Cu ²⁺的分析方法，线性响应范围为 0.20 至 1.20  mg  L ^-1，检测限和定量限分别为 0.060 和 0.20  mg  L ^-1，远低于其他基于聚合物基质的方法含有天然染料。该方法成功应用于卡莎萨酒和自来水样品中Cu ^{2+的测定，达到了较高的准确度（回收率96-104%）和精密度（相对标准偏差< 6.7%）。}我们的研究结果代表了基于天然染料的传感器领域的进步，表明此类传感器无需复杂的样品制备方法即可实现高灵敏度。