The Determination of Cr(VI)Contents in Amorphophallas konjac in Different Regions

[Objective] The aim was to determine Cr(Ⅵ)contents in Amorphophallas konjac in different regions.[Method] Under the presence of cationic surface active agent,namely,Cetyltnimethyl Ammonium Bromide(CTMAB),o-HPF and colour reaction of Cr(Ⅵ)were used to determinate the contents of Cr(Ⅵ).[Result] Under the conditions of Methylamine Tetramine-HCl buffer solution(pH=5.4),Cr(Ⅵ) mixed with o-HPF and CTMAB and formed ternary complex with the maximum absorption at the wavelength of 555 nm and molar absorption coefficient was e=9.672×104 L/(mol·cm).The molar ratio(Cr(Ⅵ)∶o-HPF) was 1∶2 in complex.Beers law was obeyed in the concentration range for Cr(Ⅵ)of 0-5 μg/10 ml.Results indicated that Cr(Ⅵ)contents in Changyang County Qinggangba Village,Zigui County Zhaojiasha Village,Zigui County Baiheshan Village were 0.609,1.839 and 0.800 μg/g,respectively.[Conclusion]The proposed methods can be applied to determine Cr(Ⅵ)contents in Amorphophallas konjac in different regions.