The Application of Using Natural Reagent Extracted from Purple Sweet Potato for Naked-Eye Detection of Copper in Water Samples


Warangkhana Khaodee Ratikon Wongkiti Suphatta Madang


     Reagent extracted from purple sweet potato was used to enable detection of Cu2+ in water by the naked-eye. The optimum conditions for this were determined by adding 10 mL of reagent to a mixture of 500 mL of buffer pH 7 (0.01 M) and a 200 mL water sample. The lowest concentration of Cu2+ able to be detected by the naked-eye was 3x10-4 M without any interfering effects. This method was validated by comparing Cu2+ concentration detected with the AAS technique. The results show that Cu2+ concentrations obtained from both techniques were similar.

Keywords: Purple sweet potato, Copper (II), Anthocyanin, Cyanidin, Naked-eye detection


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Research Articles


How to Cite
KHAODEE, Warangkhana; WONGKITI, Ratikon; MADANG, Suphatta. The Application of Using Natural Reagent Extracted from Purple Sweet Potato for Naked-Eye Detection of Copper in Water Samples. Naresuan University Journal: Science and Technology (NUJST), [S.l.], v. 26, n. 3, p. 181-188, sep. 2018. ISSN 2539-553X. Available at: <>. Date accessed: 09 feb. 2023. doi: