Chemical Modification of Ag Nanoparticles Coated Cotton Textile with Valdecoxib Derivate and Study of its Electrochemical Behavior

Electrically conductive textiles have been of increasing research interest due to potential application in clothing as well as in the medical and military fields, as sensors, actuators, electromagnetic shields etc. In this study, conductive cotton textile was prepared by in situ synthesis of Ag nanoparticles using inkjet printing on surface textile. For preparation of flexible electrode, conductive textiles was coated with hydrophobic agent contain potassium trimethoxy methyl silane, then with waterproof glue (PVA) was attached on plastic film. Different printing procedures for achievement of highest conductivity were examined, that its results are presented in Table 1. Table 1- The surface resistance of printing procedures with inkjet printer on fabric printing procedures Width (mm) surface resistance )Ω( of two point with distance 2 cm AS 5 8700 ASA 5 1300 AASSAA 5 150 AAAASS 5 8 * A= Once printing Ascorbic Acid solution (2.0 M) and S= Once printing AgNO3 solution (1.0 M). Electrochemical experiments were performed with a μ-Autolab potentiostat (Eco Chemie Utrecht) with GPES 4.9 software. The cell was equipped with a flexible electrode as a working electrode, a platinum electrode as an auxiliary electrode and a Ag/AgCl /3 M KCl as a reference electrode. The prepared flexible electrodes was immersed in 0.1 M phosphate buffer solution (pH 7.0) and cyclic voltammetry (CV) experiments was conducted in − 0.4 to 1.1 V at a sweep rate of 20 mV/S. The resulted CVs were compared to confirm the performance of the every printing procedures (Fig. 1). Redox characteristic peaks is not observed in of the graphs of a, b and c, however, in graph (d), an oxidation peak and a reduction peak is observed at 0.58 V and - 0.073 310 V, which are related to the redox of silver. Thus AAAASS procedure as proper design to prepare a flexible electrode is chosen. The Valdecoxib derivative modified Flexible Electrode (VFE) was prepared by the self-assembling technique, just by placing 20.0 μL of a 1.0 mM Valdecoxib derivative solution directly onto the FE surface and drying it at room temperature. Fig. 1. Cyclic voltammogram of Ag nanoparticles coated textile with procedure (a) AS; (b) ASA; (c) AASSAA; (d) AAAASS in 0.1 M phosphate buffer solution (pH 7.0). The CVs of VFE in a 0.1 M phosphate buffer (pH = 7.0) at various scan rates (10-70 mV/S) are shown in Fig. 2. As shown in Fig. 2, the ratio of cathodic-to-anodic peak currents obtained at various scan rates is almost constant. Furthermore, the cathodic and anodic currents increase linearly with the scan rate in the whole worked scan rate potentials as predicted theoretically for a surface-immobilized redox couple. The linear dependence indicates that the nature of the redox process is diffusionless and controlled. Fig. 2. Cyclic voltammetric responses of VFE in 0.1 M phosphate buffer (pH = 7.0) at different scan rates.