Molecularly imprinted solid phase extraction before CoQ10 analysis from two complex matrices.

CONTIN MARIO; GARCIA BECERRA CRISTIAN; MORETTON MARCELA; FLOR SABRINA; CHIAPPETTA DIEGO; LUCANGIOLI SILVIA; TRIPODI VALERIA

Conferencia; International CoQ10 association conference; 2015

Molecular imprinting is a strategy to introduce a 'molecular memory' in a polymeric system obtaining materials with specific recognition properties (1).Molecularly imprinted polymers (MIPs) are usually developed by mixing a template molecule with functional monomers, a cross-linker and an initiator. After polymerization, the template molecules are removed making the binding sites and the cavities, which are complementary to the template in size, shape and functionality, accessible. The MIP possesses a molecular ?memory?, and thus, it is able to specifically recognize and bind the target molecule.MIPs are use as sensors, for chromatography, immunoassays, controlled drug delivery and catalysis.In a previous work we have reported for first time the use of CoQ0 as a template in the development of a molecularly imprinted polymer with the ability to recognize CoQ10 (2).In this work we present the use of this polymer in solid phase extraction (SPE) procedure before CoQ10 analysis by HPLC.In this opportunity the clean up after SPE of two matrices is presented.The first matrix is a bovine liver, were a high number of interferences were found which can led to electrodes passivate and a damage to the chromatographic column.The second matrix is CoQ10 nano-encapsulated in a polymeric nano-particle (NPs). It is known that those NPs are extremely harmful to the chromatographic column.Experimental:The polymer was synthesized by bulk polymerization using methacrylic acid (MAA) and ethylene glycol dimethaclylate (EGDMA) as monomers, CoQ0 as template and benzoyl peroxide as initiator. It was characterized by scanning electron microscopy (SEM), and superficial area (BET area).The SPE consisted in three steps, first the sample loading, then the washing step and finally the elution step. The proportion of 1-propanol: water in each step was optimized in order to favor a specific interaction.All experiments were performed with a polymer control (NIP) which is synthesized under the same conditions in the absence of the template molecule.An additional binding experiment was performed employing CoQ10 or ubichromenol (UC) in order to evaluate the specificity of the interaction expressed in terms of the ?imprinting-induced promotion of binding? (IPB), a parameter that allows the study of the efficiency of the imprinting effect..Results and discussion:The SEM analysis revealed an internal structure composed of interconnected granules, and the BET area was around 24 m2 g-1 for the MIP and 8 m2 g-1 for the NIP. The IPB values obtained when CoQ10 were employed in the binding assay was six time higher than when UC were employed, which mean that the polymer is able to bind CoQ10 selectively.The clean-up of the liver extract with the polymer as stationary phase was compared to the clean-up employing a C-18 commercial particle; the purification factor was around four times higher when the polymer was used. The MIP showed the capacity to bind CoQ10 over others compounds present in the liver.The chromatograph from the analysis of CoQ10 from the CoQ10 nano-encapsulated revealed a significant improvement when a clean-up is previously performed with the polymer.The recovery of CoQ10 was higher than 73% and a CV% lower than 8% in the biological matrix and nearly 100% of recovery and a CV% lower than 2% in the pharmaceutical matrix. Both assays where performed by triplicate in three different concentrations.Conclusion:The ability of the molecularly imprinted polymer to bind CoQ10 was successfully used in a solid phase extraction which led to improve the chromatographic analysis.The elimination of nano-particles from the pharmaceutical matrix will be important in order to expand the life time of the column and the elimination of compounds from the biological matrix as well as the pharmaceutical matrix will be important to determine CoQ10 correctly.