Aggregation of Dye on Polymer: Naphthochrome Green/PVP/Cu(II) Interaction and Determination of Cu Traces

Abstract

The interaction of naphthochrome green (NCG) with polyvinylpyrrolidone (PVP) and the complexation of NCG with Cu on PVP chain were investigated in basic medium by the spectral correction technique. The binding of NCG on PVP by the electrostatic attraction obeys the Langmuir isothermal adsorption in aqueous solution. Both the NCG–PVP aggregate and Cu–NCG–PVP ternary complex was characterized at 20°C, 40°C, and 60°C. The presence of PVP sensitized the complexation between Cu and NCG. This novel approach is sensitive and selective in the presence of citrate and has been applied to the quantitative detection of Cu traces in samples with satisfactory recovery.

Keywords:

• Spectral correction technique
• Polyvinylpyrrolidone
• Naphthochrome green
• Langmuir aggregation
• Determination of Cu traces

Acknowledgments

Financial support from both the National High Technology Research and Development Program of China (863 Program, No. 2002AA601320) and the National Natural Science Foundation of China (No. 50008011) is gratefully acknowledged.