High-sensitivity Determination of Curcumin in Human Urine Using Gemini Zwitterionic Surfactant as a Probe by Resonance Light Scattering Technique

Authors


Zhanguang Chen, Department of Chemistry, Shantou University, Shantou, 515063, China. E-mail: kqlu@stu.edu.cn

Shengwang Liang, College of Traditional Medicine, Guangdong Pharmaceutical University, Guangzhou, 515006, China. E-mail: swliang371@163.com.

ABSTRACT

Introduction

Curcumin is a popular plant medicine that is extracted from turmeric dry rhizomes of Curcuma longa Linn. The study of curcumin is well established and is currently becoming a centre of attention.

Objective

To develop a steady and simple assay for curcumin determination at the nanogram level based on the intense resonance light scattering (RLS) enhancement due to the interaction between curcumin and phosphodiesters quaternary ammonium salt (PQAS).

Methodology

PQAS, a new kind of Gemini zwitterionic surfactant, was used as the probe for the determination of curcumin by the RLS technique. A series of validation experiments was also performed.

Results

A linear relationship was constructed between the ΔIRLS and the concentration of curcumin. The linear regression equation was presented as ΔIRLS = 8.37 + 44.92c (µg/mL) with the regression coefficient r = 0.9987 (n = 12) and the linear range was 0.08–60.0 µg/mL. The detection limit (3σ) was 2.6 ng/mL.

Conclusion

The proposed method can be used to detect the content of curcumin in human urine samples and this new assay using PQAS as a probe was more sensitive and displayed a wider linear range than that reported previously. Copyright © 2011 John Wiley & Sons, Ltd.

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