A new electrochemical sensor based on molecularly imprinted polymer for determination of biotin in drug sample

Biotin, which is an essential vitamin H, helps in the health of skin, nerve and digestive system, and assists in releasing energy and metabolism of fats, protein and carbohydrates. It also helps in the formation of embryonic development. It has wide function and effects on systemic processes and development assistance in immunity. Determination of biotin in foodstuffs is important, because appropriate biotin intake is beneficial in attaining a good quality of life, better health and development of children and adults, improved physical mechanisms that combat aging and disease and efficient mental capacity [1]. The analysis of biotin in foodstuff and tissue and body fluids by high-performance liquid chromatographic (HPLC), luminescence, spectrophotometric, fluorometric has been reported. Due to their excellent rapid response, excellent sensitivity, simplicity, low cost and vivo detection, electrochemical sensors (e.g). voltammetric, potentiometric, conductimertic and capacitance) have obtained wide application in medical, biological and environmental analysis. In the recent years there has been an increasing interest in the modification of electrode̛ s surface with a molecularly imprinted polymer (MIP) to enhance selectivity Generally, MIPs are synthetic polymers able to selectively recognize a template molecule in an easy and a rapid way. The synthetic procedure is cheap and MIPs are stable under harsh conditions of pH and temperature. Basically, MIPs are prepared by the polymerization of a suitable monomer and a cross- linker agent in the present of a template. After polymerization, the template is removed and a polymer matrix, which is complementary in shape and functionality to the template, is obtained. Thus, the polymer has the ability to selectively link to the target analyte [2]. In this work, a new and selective electrochemical sensor was introduced by electropolymerization of the functional monomer and molecularly imprinted polymer (MIP) which was synthesized onto a glassy carbon electrode (GCE) in aqueous solution using 13th Annual Electrochemistry Seminar of Iran Materials and Energy Research Center (MERC), 22- 23 Nov, 2017 75 cyclic voltammetry in the present of biotin as template. The imprinting effect was verified by comparing electrochemical response of MIP and none imprinted polymer (NIP) tested by cyclic voltammetry between -0.6 and 0.8 V in redox peak currents of hexacyanoferrate. As shown in Fig.1. Several important parameters affecting sensor response were optimized and the DPVs of the MIP/GCE for biotin under the optimized experimental conditions are shown in Fig. 2. It can be seen that the peak current decreases as the concentration of biotin increased, which suggested that more and more binding sites in the film are occupied by biotin molecules. Furthermore, they present fine linear relationship in the range from 1 to 95 μM the regression equation is Ip=0.027c+1.34 (R2=0.997. The detection limit was 0.3 μM (S/N=3). The result of this research demonstrate that the new sensor is sensitive, simple to construct and easy to operate. This imprinted electrochemical sensor was used successfully applied to the determination of biotin in real sample.