High enhancement of macro and micronutrients quantification in Cajuína by ICP OES using ultrasound and multivariate analysis

A fast, safe, simple, and low-cost analytical method was developed for the determination of macro and microelements in Cajuína samples from Brazil combining UAE and ICP OES. A multiplexed approach using experimental designs was applied for method optimization. The optimal conditions were using 4 mL of 8 mol L−1 HNO3 and 1.5 mL H2O2 under 30 min of sonication. The detectability of the method has been improved. The precision was RSD < 5.5% while the accuracy of the method ranged from 87% to 108% as well as the results were in agreement with the reference method. The analysis of 38 samples of Cajuína juices presented a mean of Ca, Cu, Fe, K, Mg, Na, P, S and Zn of 8.70, 0.10, 0.97, 1223, 112, 60.1, 83.9, 65.1, and 0.99 mg L−1. So, the proposed analytical method demonstrated feasibility for the simultaneous determination of mineral nutrients in similar matrices as beverage.