CONICET | Buscador de Institutos y Recursos Humanos

Solid phase extraction with molecularly imprinted polymers for selective determination of propylparaben in personal care products The use of parabens as microbiological preservatives in cosmetic formulations has spread in last years due to their low cost and efficiency. However, it has been reported that these compounds can act as endocrine disruptors and the chronic exposure to high dose increases the risk of inducing breast cancer.The determination of analytes present in low concentrations in complex matrices, requires the implementation of a sample pretreatment step for improving the selectivity and sensitivity of the used methodology. The complexity of cosmetic and personal care products encouraged us to develop a method of solid phase extraction (SPE) based on molecular recognition, molecularly imprinted solid phase extraction (MISPE).In this work, two columns filled with the most commonly used sorbent types for off-line SPE, silica gel and C18 were used for propylparaben (PP) separation/preconcentration. A third column was filled with a molecularly imprinted polymer (MIP) synthetized for our group by using PP as template molecule. The samples were passed through the columns and the retention and subsequent elution in each case was monitored by HPLC. Propylparaben was specifically retained (97%) by MIP and non-specifically on C18 (100%) while it was not retained on silica column.The selected elution solvent was ethanol-water 80:20 (v/v) and the elution flow rate which showed the best performance was 1 mL min-1. A high PP percentage (89%) was removed of the MIP with the first milliliter of the solvent and the total analyte elution was achieved by using additional 2 mL. The PP elution of C18 column was not achieved even after extensive washing (> 7 mL).MISPE resulted a rapidly developing technique that allowed the determination of the target molecule in baby and antibacterial wipes without interferences within a concentration range 0.02-0.2 mg mL-1. Besides its high selectivity, MIPs showed low cost, high stability, mechanical and thermal strength and can be used in a wide range of media and they have the ability to be reused without loss of activity.