Visible spectrophotometric determination of heavy metals in commercial soaps

• Main Author: Chan, Cindy A.
• Format: text
• Language: English
• Published: Animo Repository 1994
• Subjects: Spectrophotometry; Heavy metals; Metals; Soap; Chemistry
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/2989
• Institution: De La Salle University

The amount of Zinc, Copper and Iron content in different locally manufactured brands of soaps namely Coco soap, Perla soap, Johnsons baby soap and Safeguard were determined using Hitachi U-2000 UV-Visible spectrophotometer. Elimination of possible interference was carried out by carefully adjusting the pH, precipitation and extraction of metals other than the analyte and proper selection of working wavelengths. The metals were complexed with appropriate ligands zinc with dithizone at \max = 555.5 nm., copper with EDIA at \max = 596.0 nm. and iron with thiocyanate at \max = 474.0 nm. The concentrations of these metals were obtained from their respective standard calibration curves. Among the four soaps, Coco soap has the highest concentration of iron, copper and zinc.