Fig. 1. Simultaneous ECL and SWV from a sensor featuring (RuPVP/DNA)₃/(cyt P450_cam/DNA)₂ films on PG electrodes in pH 5.5 acetate buffer before (0 min) and after (4 min) incubations at 37 °C with 2% styrene and 0.5 mM H₂O₂ (a) integrated ECL intensity (counts/s) vs. potential profiles and (b) SWV amplitude, 25 mV; frequency, 5 Hz; step, 4 mV.

Fig. 2. Influence of incubation time on the final/initial ECL (●) and SWV () ratios for sensors featuring (RuPVP/DNA)₃/(cyt P450_cam/DNA)₂ films incubated at 37 °C with 2% styrene + 0.5 mM H₂O₂, and controls using 0.5 mM H₂O₂ alone for ECL (○) and SWV ().

Fig. 3. Influence of incubation time on the final/initial ECL (●) and SWV () ratios for sensors featuring (RuPVP/DNA)₃/(Mb/DNA)₂ films reacted at 37 °C with saturated styrene and 0.5 mM H₂O₂, controls using 0.5 mM H₂O₂ alone for ECL (○)and SWV (), and controls using styrene alone for ECL (□) and SWV ().

Scheme 1. Conceptual drawing of sensor system for simultaneous ECL and voltammetry detection. The SCE reference electrode (a), PG working electrode (b) and Pt counter electrode (c) are located in a glass cell with an extended cylindrical glass base. A fiber optic cable (d) is located on the outside of the cell directly underneath the sensor surface. RuPVP, DNA (brown), and enzyme (blue) layers forming the active sensor film are shown to the right. The structure of RuPVP is shown at the top. For clarity, only one layer of RuPVP is shown on the sensor, although several can be used to enhance S/N. (For interpretation of the references to color in this scheme legend, the reader is referred to the web version of the article.)

Average characteristics of metallopolymer/DNA/enzyme films from QCM results

Relative rate of DNA damage from bioactivation of styrene by ECL and SWV