桑色素光度法测定痕量铝和聚丙烯酰胺

Spectrophotometric Determination of Trace Alminium and Polyacrylamide by Morin

基于聚丙烯酰胺（PAM）作为增稳剂时，铝与桑色素（Morin）之间的显色反应，提出了一种简便、快速、高灵敏测定痕量铝的光度法。铬合物组成比为A1：Morin=1：2，表观摩尔吸光系数。铝浓度在0.04～0.28ng/mg范围内服从比尔定律，检测限4.0×10-10g/L发现PAM和Morin之间可形成另一种络合物并能用于PAM的测定，该络合物在350nm处的吸收峰强度与PAM浓度在0.02～0.1mg/L范围内成正比，检出限2.0×10-7g/L。所提出的方法用于水样中AL和PAM的不经分离测定，结果满意。

A simple, rapid and highly sensitive spectrophotometrc method for determining Al has been developed based on the colour reaction Al3+ with Morin in the presence of polyacrylamine (PAM) function as stabilizer. The complex composition radio is Al:Morin=1.2. The apparent 408 is 6.3×107L·mol-1·cm-1 at nm. Beer's law is obeyed in the range of 0.04 to 0.28ng/mL and the detection limit is 4.0×10-10g/L for Al. It was also found that another complex was formed between PAM and Morin can be used to determine PAM. The intensity of absorbtion peak at 350nm is in proportion to the concentration of PAM in the range of 0.02 to 0.10 mg/mL, and the detection limit is 2.0×107g/L. The methods have been proved are satisfactrory for determination of Al and PAM in the water samples without seperation.