Selective determination of chloramphenicol at trace level in milk samples by the electrode modified with molecularly imprinted polymer

A novel voltammetric sensor for determination of chloramphenicol (CAP) in milk samples was introduced. The CAP selective molecularly imprinted polymer (MIP) and non imprinted polymer (NIP) were synthesized and then added to the carbon paste (CP) electrode composition in order to prepare MIP-CP electrode. The MIP, embedded in the carbon paste electrode, acted as the selective recognition element and pre-concentrator agent for CAP. CAP was extracted in the electrode for a definite time and then it was analyzed by differential pulse voltametry, found to be an effective determination method. The MIP-CP showed very high CAP recognition ability, compared to NIP-CP. The electrode washing, after CAP extraction, led to an enhanced selectivity. Various factors, known to affect the response behavior of the electrode, were investigated and optimized. This sensor showed a linear response range of 8.0 × 10−9−1.0 × 10−6 M and lower detection limit of 2.0 × 10−9 M (S/N = 3). The sensor was successfully applied to the determination of CAP in milk samples.