**2. Materials and methods**

#### **2.1 Materials**

Tragacanth gum (T) and chitosan were purchased from Sigma-Aldrich Company. Reactive red 35 (RR35), reactive yellow 15 (RY15), and acid black 194 (AB194) were obtained from Burboya Company. Zinc nitrate hexahydrate (Zn(NO3)2·6H2O), glacial acetic acid (glacial 100%, pro analysis), and sodium hydroxide (NaOH) were purchased from Merck Company. MF-Millipore™ membrane filter was purchased from Merck Company. Ultrapure water was provided by a human ultrapure water system (water resistance: 18.3 Mohm) and was used for the preparation of all reactive dye solutions as analytes. All electrochemical gold transducers and voltammetric electrochemical workstation were purchased from Ebtro Electronics.

**5**

**Figure 1.**

*3D model structure and property of the reactive dyes.*

*A Novel Electrochemical Sensor for the Detection of Reactive Red Dye to Determine Water Quality*

Tragacanth gum/chitosan/ZnO nanoprisms were prepared using a green sonochemical method at 25°C (35 kHz frequency, 320 W, Sonoplus, Bandelin, Germany). In the first step, 0.1 g of tragacanth gum was dissolved in 50 ml of deionized pure water on a magnetic stirrer in 2 h at 25°C. In the second step, 0.1 g of chitosan was dissolved in 50 ml of 2% glacial acetic acid. In the third step, 25 ml of the prepared solutions was taken and mixed. In the fourth step, O.1 M of Zn(NO3)2·6H2O and 0.2 M of NaOH was prepared in deionized pure water. In the fifth stage, the solution of Zn(NO3)2·6H2O was added in the solutions, and then the solution of NaOH was added dropwise under the sonicator at 25°C for 40 min (%30 amp). The solution was kept at 24 h in the dark at room temperature. Then, it was first filtered through membrane filters of 0.45 μm and 0.22 μm pore size, respectively. The final solution (viscosity: 1.28 cP and pH 4) was stored at 25°C for

*DOI: http://dx.doi.org/10.5772/intechopen.92280*

use in the sterile container for analysis.

used are shown in **Figure 1**.

**2.2 Synthesis of tragacanth gum/chitosan/ZnO nanoprism**

**2.3 Preparation and measurements of electrochemical sensors**

Electrochemical gold transducers were rinsed with ultrapure water, dried with nitrogen gas, and coated with tragacanth gum/chitosan/ZnO nanoprism solution by dropping and drying the solution. The 3D model structure and the property of dyes

The potential of the working electrode was varied linearly with time, while the reference electrode was maintained at a constant potential. The potential was *A Novel Electrochemical Sensor for the Detection of Reactive Red Dye to Determine Water Quality DOI: http://dx.doi.org/10.5772/intechopen.92280*
