基于可见的颜色变化检测样本中的卡尔米尼酸的快速色度测量方法
Azra Akbar1, Amna Jabbar Siddiqui2, Syed Tarique Moin3
1H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
概括
一种新的,快速的方法检测卡尔米尼酸 (CA),一种来自昆虫的食品染料,使用复合. 这种简单的技术提供了视觉颜色的变化,帮助素食主义者和素食主义者消费者和食品当局快速识别.
科学领域:
- 分析化学 分析化学
- 食品科学 食品科学 食品科学
背景情况:
- 卡尔米尼酸 (CA) 是一种广泛用于食品和非食品产品中的昆虫衍生红色染料.
- 由于素食主义者和素食主义者的饮食限制,对CA的检测至关重要.
- 食品当局需要快速可靠的检测方法.
研究的目的:
- 开发一种简单,快速和有效的对卡尔米尼酸 (CA) 的定性检测方法.
- 为了利用 (II) 离子 (Pb2+) 来形成可检测的CA-Pb2+复合体.
- 通过开发两种不同的检测方法来解决来自铁离子 (Fe2+) 的潜在干扰.
主要方法:
- 使用Pb2+进行复杂形成的CA的定性检测,导致可见的颜色变化 (粉红色到紫色).
- 在λmax=605nm的光谱分析以量化CA-Pb2+复合体.
- 开发了两种方法:方法I (没有NaF) 和方法II (使用NaF防止CA-Fe2+复合).
- 通过一天内和一天内分析和选45个商业样本的方法验证.
主要成果:
- 一个可见的粉红色到紫色的颜色变化表明在添加Pb2+时存在CA.
- 该CA-Pb2+复合体表现出一个低颜色转移,可在605nm测量.
- 方法I实现了LOD和LOQ分别为0.0025和0.0076毫克毫升-1.
- 方法II实现了分别为0.0136毫克和0.0415毫克的LOD和LOQ.
- 开发的方法得到了成功的验证,并应用于选商业食品和非食品样品.
结论:
- 一种简单,快速和光谱测量支持的方法已成功开发,用于使用Pb2+复合的CA检测.
- 在方法II中加入化 (NaF) 有效地防止铁离子的干扰,提高检测可靠性.
- 这些方法适用于在不需要复杂仪器的情况下对各种产品中的CA进行常规监测.
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