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Supporting Information

Self-cleaning properties in engineered sensors for

dopamine electroanalytical detection

Guido Soliveri,a,b Valentina Pifferi,a,b Guido Panzarasa,c Silvia Ardizzone,a,b Giuseppe

Cappelletti, a.b Daniela Meroni, a,b Katia Sparnacci,c and Luigi Falciola*,a,b

a Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy.

b Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), Via

Giusti 9, 50121 Firenze, Italy.

c Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale “Amedeo

Avogadro”, Viale T. Michel 11, 15100 Alessandria, Italy.

Electronic Supplementary Material (ESI) for Analyst.This journal is © The Royal Society of Chemistry 2015

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Record 36: AgNPs SB(2) 15_10_2014 5

Figure S1. Z-potential spectrum obtained for the aqueous suspension of Ag NPs.

Figure S2. Photograph of the final device on a printed white paper with the logo of the Università degli Studi di Milano, in order to show transparency properties.

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Figure S3. FILMETRICS® analysis of a SiO2 – Ag – TiO2 sandwich obtained on silicon wafer. The thicknesses of the SiO2 and TiO2 layers (Ag could be neglected) were obtained by comparing the experimental reflectance spectrum (blue) with the one calculated by the software (red) using the

following layered model using indicative values for the layers:Si (substrate, infinite) – SiO2 (800 nm, vary) – TiO2 Amorphous (200 nm, vary) – Air.

Final results were the average of at least three measurements.

Figure S4. Scanning electron microscopy top picture of the titania top layer in the final device.

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Figure S5. Bode plots for all the tested electrodes, registered at + 0.1 V (SCE) in the presence of the model probe molecule K4[Fe(CN6)].

Figure S6. Differential pulse voltammograms registered for consecutive additions of dopamine at FTO+Ag+TiO2 electrode.

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Figure S7. Emission spectrum of the UV iron halogenide lamp Jelosil HG500.