Highly sensitive electrochemical luminescence determination of thiamine Original Research Article

A highly sensitive electrochemical luminescence (ECL) method has been developed for the determination of thiamine based on electrochemically oxidizing thiamine with rhodamine B as a sensitizer. A weak ECL signal of thiamine was electrochemically generated on a platinum electrode in an alkaline solution and strongly enhanced in the presence of rhodamine B. Under the condition of 0.10 mM rhodamine B, 6 mM CTMAB and 0.36 M sodium hydroxide, the response to the concentration of thiamine is linear range from 0.1 μg ml−1 to 2 μg ml−1 and a detection limit of 0.08 μg ml−1 can be achieved. This method has been successfully applied to the determination of thiamine in pharmaceutical preparations. The energy transfer ECL scheme is also postulated.