Ansari Rehana, Kazi Tasneem G, Jamali Mohammad K, Arain Mohammad B, Sherazi Syed T, Jalbani Nusrat, Afridi Hassan I
National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan.
J AOAC Int. 2008 Mar-Apr;91(2):400-7.
A simple and fast procedure is proposed for the extraction of iron (Fe), copper (Cu), and nickel (Ni) in 16 varieties of sunflower seed oil samples using an ultrasonic bath. The experimental parameters of the ultrasonic-assisted extraction (UAE) method were optimized to improve the sensitivity and detect the metals at trace levels in minimum time. Conventional wet acid digestion method was used for comparative purposes. The optimum recovery of all 3 metals was obtained by UAE for 7 min, while the separation of aqueous and organic phases after extraction using centrifugation (UAE-2) required 3 min, as compared to the conventional equilibration method (UAE-1) that required 90 min. The respective recoveries of Cu, Fe, and Ni obtained with UAE-2 were in the range of 95.8-97.5, 93.5-98.3, and 95.6-98.2%, respectively, for different varieties of sunflower oil samples. Accuracy was determined by the standard addition method. Under the optimum operating conditions, the limits of detection obtained from the standard addition curves were 21.7, 20.4, and 35.6 ng/mL for Fe, Cu, and Ni, respectively. The fact that all varieties of sunflower oil contain significant amounts of Fe, Cu, and Ni indicates the deterioration of sunflower oil quality immediately after extraction from seeds, which poses a threat to oil quality and human health.
本文提出了一种简单快速的方法，用于使用超声浴提取16种葵花籽油样品中的铁（Fe）、铜（Cu）和镍（Ni）。对超声辅助萃取（UAE）方法的实验参数进行了优化，以提高灵敏度并在最短时间内检测痕量水平的金属。使用传统的湿酸消解方法进行对比。UAE方法在7分钟时可获得所有3种金属的最佳回收率，而与需要90分钟的传统平衡方法（UAE-1）相比，使用离心法（UAE-2）萃取后水相和有机相的分离需要3分钟。对于不同品种的葵花籽油样品，UAE-2法获得的Cu、Fe和Ni的回收率分别在95.8-97.5%、93.5-98.3%和95.6-98.2%范围内。通过标准加入法确定准确度。在最佳操作条件下，从标准加入曲线获得的Fe、Cu和Ni的检测限分别为21.7、20.4和35.6 ng/mL。所有品种的葵花籽油都含有大量的Fe、Cu和Ni，这一事实表明葵花籽油从种子中提取后质量立即恶化，这对油的质量和人类健康构成威胁。
