A new enzyme-catalytic resonance scattering assay for glucose in serum using cationic surfactant

In acetic acid buffer solution, glucose oxidase (GOD) catalyzed the dissolved oxygen oxidation of glucose to form H(2)O(2). In succession, horseradish peroxidase (HRP) catalyzed the H(2)O(2) oxidizing excess I(-) to form I(3)(-). The I(3)(-) combined with a cationic surfactant (CS) such as tetradecyl dimethyl benzyl ammonium chloride (TDMBA) to produce TDMBA-I(3) association particles that exhibited the strongest resonance scattering (RS) peak at 460 nm. The enhanced RS intensity at 460 nm was linear with glucose concentration in the range of 2.0 x 10(-8)-2.0 x 10(-6) mol/L, with a detection limit of 8.5 x 10(-9) mol/L. The glucose in serum samples were assayed by the enzyme catalytic RS assay and by spectrophotometry. The results of both assays showed a close correlation. This assay has simplicity, sensitivity and good specificity for quantitative determination of glucose.