Rapid Low-Cost Determination of Lead(II) in Cassava by an iPod-Based Digital Imaging Colorimeter

An iPod-based digital image colorimeter was developed for the determination of lead(II) in cassava. The method is based on the color values of a lead(II) solution following its reaction with dithizone. Lead(II) from cassava was extracted using an ultraviolet-digestion unit followed by the color-forming reaction and image capture using the ColorConc application operated on an iPod touch. The concentration was predicted by comparing the color values with those collected in a database. The time needed for complete digestion was 30 min. The determined concentrations of lead(II) were from 0.10 to 1.00 mu g mL(-1). The limits of detection and quantitation were 0.0120 and 0.0399 mu g mL(-1), respectively. The recovery values were 105 +/- 7.07% and 109 +/- 6.61% at 0.2 mu g mL(-1) and 0.4 mu g mL(-1) lead(II) (n = 5). The reported method was demonstrated to be simple, accurate, rapid, precise, and low cost.