A new method for the determination of ethanol based on the immobilized enzyme fluorescence capillary analysis (IE-EFCA) was proposed. Alcohol dehydrogenation (ADH) was immobilized in inner surface of a capillary. After NAD+ as an oxidizer was mixed with the samples solution, the determination was conducted to the mixed solution in the capillary at 350 nm of excited wavelength and at 459 nm of emission wavelength. The experimental conditions for ethanol determination are as follows: reaction time is 20 min, temperature is 40 ℃, the concentrations of phosphate buffer solution (pH 7.5) and NAD+ are 0.1 mol/L and 5 mmol/L, respectively; immobilization concentration of ADH is 10 U/L. The linear range for the determination of ethanol is 2.0~15.0 g/L, r>0.9958, the detection limit of ethanol is 1.1 g/L, RSD is 1.9%. IE-EFCA method is applicable for the determination of the alcohol samples in medicine, industry, grocery, and environment.
