Chemiluminescence microfluidic chip fabricated in PMMA for determination of benzoyl peroxide in flour

A rapid and sensitive chemiluminescence microfluidic chip fabricated in polymethyl methacrylate for determination of benzoyl peroxide in flour is described. The width of the microchannel was 200 μm and the depth was 100 μm in the chip (50 × 40 × 5 mm). The total length of the microchannel was 67 mm with the detection area of 5 × 5 mm. Benzoyl peroxide can directly oxidize luminol to produce chemiluminescence. Two injectors of double-tee injector and microvalve injector were used. The sampling volume was 0.16μl for the double-tee injector and 0.25μl for the microvalve injector. The linear range of the benzoyl peroxide concentration was 8 × 10−7–1 × 10−4 g/ml. The detection limit was 4 × 10−7 g/ml and the R.S.D for eight times is 3.06% for the double-tee injector and 2.41% for the microvalve injector. The proposed method has been successfully applied to the determination of benzoyl peroxide in flour.