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Objective: electrochemical enzyme sensor to detect organic pollutants in the analysis of environmental easy shortcut characteristics. The concentration of organic pollutants in this study using sequential injection analysis (SIA) of the screen printing type enzyme sensor coupled with the detection of horseradish peroxidase (horseradish peroxidas, HRP) and laccase catalytic current, reflecting phenols . Rapid Determination of environmental pollutants provides an accurate and sensitive detection technology and automation. Methods: Experimental Study in units point HRP, laccase screen printed electrode and four point (HRP, laccase) Screen printed electrode base, using bovine serum albumin (BSA) and glutaraldehyde forming crosslinked molecules will HRP, laccase or two enzymes with the osmium polymer (osmium - polyvinylpyridine, Os (bpy) 2 (PVP) 10 Cl 2 , OS-PVP) mixed enzyme solution are respectively fixed in units point screen printed electrode and four point electrode surface, using sequential injection analysis (SIA), and screen printing biosensor associated usage of various enzyme electrodes were detected and analyzed, and the experimental conditions to optimize its buffer pH and concentration, pump flow rate, sample volume. Results: (1) on the unit points, non-Os-PVP modified HRP modified electrode free of ferricyanide Laccase Electrode detection analysis, optimized to obtain optimal conditions for ① HRP electrode: the pump flow 153.9μL/min, samples The amount of 100 μL, and 0.1 mol / L, pH 6.5 in PBS buffer, the HRP catalyzed phthalic diamine (OPD)-H 2 O 2 reaction, H concentration changes in the current 2 O 2 response linear equation y = 14.59 114.61x R 2 = .9845, the current response sensitivity to 110.11 nA / (mmol / L), the current change of OPD concentration in response to the linear equation y = 27.595x 17.925 R 2 = 0.9941, the current response sensitivity of 26.88 nA / (mmol / L) enzyme electrode reproducibility good, RSD 3.8%, for the determination of the actual water samples spiked recoveries greater than 60% recovery. ② free potassium ferricyanide laccase modified electrode: 0.1 mol / L, pH 4.5 PBS buffer, of laccase catalyzed catechol and potassium ferricyanide current response of the linear equation y = 49.7x 17.582, R < sup> 2 = 0.9827, the current response sensitivity of 50 nA / (mmol / L) showed a good linear relationship. (2) on the the units point and Os-PVP modified HRP Laccase Electrode detection analysis, the optimum conditions in PBS buffer 0.1mol / L, pH 7.5,4.5 under the HRP catalytic OPD-H 2 O 2 reaction current response linear equation y = 300.39x-6.7031, the R 2 = 0.9875, the current response sensitivity of 97.46 nA / (mmol / L); of Laccase catechol reaction current response of linear equations y = 1.166x 0.078 R 2 = .9801 current response sensitivity, as 1.13μA / (mmol / L). HRP-(Os-PVP) electrode for actual water samples spiked recoveries of 70% 93%. Laccase - (Os-PVP) electrode is used to detect spam filtrate containing catechol concentration average of 0.028 mmol / L, standard deviation (RSD) was 0.34%. (3) four-point analysis of the enzyme electrode in accordance with HRP, laccase, HRP, the order of laccase The enzyme Os-PVP mixed fixed to the surface of the screen-printed electrode, respectively, obtained in the optimum PBS buffer (0.15 mmol / L, pH 6.0) conditions, with H 2 O 2 , a point (HRP) catechol common response to the current response of linear equations: y = 1.572x-0.165, R 2 = 0.9559, the current response sensitivity to 1.44μA / (mmol / L); 2 locus (laccase): y = 0.5519x - 0.023, and R 2 = 0.949, the sensitivity of the current response to 0.54μA / (mmol / L); 3-bit point (HRP): y = 1.022x 0.01, and R 2 = .9604 current response sensitivity 0.91μA / (mmol / L); 4 loci (laccase): y = 0.349x-0.0042, R , 2 = 0.9641, current response sensitivity to 0.33μA / (mmol / L). Of garbage filtrate containing the concentration of catechol concentration test results were 1.09 mmol / L and 1.02 mmol / L and 1.04 mmol / L, 1.09 mmol / L, an average of 1.05 mmol / L, the relative deviation (RSD) was 3.4%. Conclusion: the establishment of a sequential injection analysis method with screen printed enzyme sensor combined with technical and four-point enzyme electrode. The hyphenated techniques improve the accuracy and sensitivity of the sensor analysis and real-time detection environment conducive to online long-term; the four enzyme electrode broaden the detection range and selectivity for complex environmental detection means.
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