A simple method for the determination of benzoic acid based on room temperature phosphorescence of 1-bromopyrene/γ-cyclodextrin complex in water.

ABSTRACT

The addition of benzoic acid (BA) to an aqueous solution of 1-bromopyrene (1-BrPy) and γ-cyclodextrin (γ-CD) was found to form a ternary 1-BrPy/γ-CD/BA inclusion complex that exhibited strong and stable room temperature phosphorescence (RTP) without deoxygenation. The effects of several different factors on the RTP emission from the inclusion complex were subsequently investigated. A good linear relationship between the RTP intensity and the concentration of BA over the range of 0-0.70mM was identified (R2=0.9917), and the detection limit was determined to be 0.68µm. Application of the new method was successfully proved for the detection of BA in various beverages with satisfactory results.