A Highly Selective Sensor for 5-Aminosalicylic acid using carbon pasteelectrode modified by MWCNT/ molecular imprinted polymer

In this work, electrooxidation behavior of drug 5-Aminosalicylic acid using multi wall carbonnanotube/ Poly methacrylic molecular imprinted polymer modified carbon past electrode(MWCNT/MIP-CPE) was investigated. The electrochemical behavior of the MWCNT/MIP-CPE fordetection of 5-Aminosalicylic acid was investigated by cyclic voltammetry (CV) and differentialpulse voltammetry (DPV). The surface feature of the modified electrode MWCNT/MIP-CPE wascharacterized by scanning electron microscopy (SEM). The MIP and non-imprinted polymers(NIP) were synthesized using 5-ASA as a template, methacrylic acid (MAA) as a monomer,ethylene glycol dimethacrylate (EGDMA) as a cross-linker and 2-Azobisisobutyronitrile (AIBN)as an initiator. All effective factors in this experiment and the interactions between them wereoptimized in six factors and five levels by Design Expert software Version 7. Based on thesoftware, minimum number of required runs was 33. In these runs, polymers were synthesizedquite carefully. All carbon paste electrodes were modified by synthesized polymers andelectrochemical measurements were performed in scan rate and pH levels that optimized by thesoftware and responses were examined by ANOVA Analysis Method. A dynamic linear range of10-500mM was obtained. The detection limit of the sensor was calculated as 4.6mM. As otherimprinted materials, one of the main functions of the proposed MWCNT/MIP-CPE was toimprove the selectivity of electrochemical sensors. Thus, this sensor was used successfully forthe 5-Aminosalicylic acid determination in a commercial pharmaceutical formulation and humanserum.

Keywords:

functional multi-walled carbon nanotubes , molecularly imprinted polymer , 5-aminosalicylic acid , non-imprinted polymer , differential pulse voltammetry