Marzieh Alizadeh

Analysis of food, pharmaceutical, and environmental compounds is an inevitable issue to evaluate quality of the compounds used in human life. Quality of drinking water, food products, and pharmaceutical compounds is directly associated with human health. Presence of forbidden additives in food products, toxic compounds in water samples and drugs with low quality lead to important problems for human health. Therefore, attention to analytical strategy for investigation of quality of food, pharmaceutical, and environmental compounds and monitoring presence of forbidden compounds in materials used by humans has increased in recent years. Analytical methods help to identify and quantify both permissible and unauthorized compounds present in the materials used in human daily life. Among analytical methods, electrochemical methods have been shown to have more advantages compared to other analytical methods due to their portability and low cost. Most of big companies have applied this type of analytical methods because of their fast and selective analysis. Due to simple operation and high diversity of electroanalytical sensors, these types of sensors are expected to be the future generation of analytical systems. Therefore, many scientists and researchers have focused on designing and fabrication of electroanalytical sensors with good selectivity and high sensitivity for different types of compounds such as drugs, food, and environmental pollutants. In this paper, we described the mechanism and different examples of DNA, enzymatic and electro-catalytic methods for electroanalytical determination of drug, food and environmental compounds.

Daunorubicin is a famous anthracycline anticancer chemotherapy drug with many side effects that is very important to measure in biological samples. A daunorubicin electrochemical biosensor was fabricated in this study using ds-DNA as the biorecognition element and glassy carbon electrode (GCE) amplified by Pt/SWCNTs as a sensor. The synthetization of Pt/SWCNTs was done by the polyol method, and their characterization was accomplished via XRD, EDS, and TEM methods. The results showed a diameter of about 5.0 nm for the Pt nanoparticle decorated at the surface of SWCNTs. The morphological and conductivity properties of Pt/SWCNTs/GCE were investigated by EIS and AFM methods, and the results confirmed that Pt/SWCNTs/GCE had a high surface area and high conductivity. ds-DNA/Pt/SWCNTs/GCE showed an oxidation signal relative to that of the guanine base at the potential of 847 mV and a positive shift after interaction with the daunorubicin anticancer drug. This point confirms the intercalation reaction between the guanine base in the ds-DNA structure and the drug that could be used as an analytical factor for the determination of daunorubicin. Furthermore, molecular docking study is used to predict the interaction site of daunorubicin with DNA. It is found that daunorubicin interacts with guanine bases of DNA via an intercalative mode. Kinetic investigation showed an association equilibrium constant (Ka) of about 5.044 × 103 M–1 between ds-DNA and daunorubicin. The differential pulse voltammetric results showed a linear dynamic range of 4.0 nM to 250.0 μM with a detection limit of 1.0 nM for determination of daunorubicin on the surface of ds-DNA/Pt/SWCNTs/GCE. Finally, ds-DNA/Pt/SWCNTs/GCE was successfully used for the determination of daunorubicin in injection samples with a recovery range of 98.27–10313%.