Validation and quantitative analysis of cadmium and lead in snake fruit by flame atomic absorption spectrophotometry

Snake fruit or known as Salak is one of the favorite fruits which is consumed not only in Indonesia but also in the worldwide. The fruit may be contaminated with heavy toxic metals like cadmium (Cd) and lead (Pb). As a consequence, the validation of analytical methods for determination of these heavy metals is continuously developed. Flame Atomic Absorption Spectrophotometer (FAAS) for determination of Cd and Pb in snake fruit has been validated. The developed method was linear over the concentration ranges of 0,01 -1,0 μg/mL (Cd) and 0,10 – 2,00 μg/mL (Pb). The correlation coefficient (r) obtained for both regressions is higher than 0.99. Limit of detection (LOD) of Cd and Pb were found to be 0,004 μg/mL and 0,04 μg/mL respectively, while limit of quantitation (LOQ) were found to be 0,01 μg/mL (Cd) and 0,1 μg/mL (Pb), respectively. This method was accurate and precise enough for determination of these heavy metals in snake fruit sample which were indicated by the acceptable recovery and low values of relative standard deviation. The developed method has been successfully used for determination of Cd and Pb levels in snake fruit commercially available in the markets.