Comparison of Solid Phase Extraction Based on MIP and DLLME for Separation of Fenpyroximate Pesticide from Aqueous solution

Abstract

In this paper, we evaluate the performance of molecular-imprinted polymer (MIP) and dispersive liquid-liquid microextraction (DLLME) methods for extraction and separation of Fenpyroximate (Fen) pesticide from aqueous samples. The effective parameters for pesticide microextraction such as adsorbent dose, pH, contact time, stirring rate, to achieve high removal percentage were studied using the response surface method. The effect of influencing factors on microextraction, such as type and volume ratio of dispersive and extractive solvents, salt concentration, pH, and extraction time were investigated and optimized. The maximum recovery) 94 %( of the pesticide was obtained using 0.55 wt. % MIP as an adsorbent in pesticide solution with pH 5.9 at 512 rpm on 58 minutes. However, the recovery efficiency (93%) was achieved by DLLME with an extraction solvent-to- dispersive volume ratio of 25 /75, the salt concentration of 3.5 wt. %, and pH 6.0, during 72 seconds of extraction time. This high separation efficiency is achieved in a very short time. The reason is the structure of this method, because in DLLME the transfer level of aqueous and organic phases reaches its maximum value, and as a result, the largest extraction will be achieved. The results showed that both extraction methods have high potential to effectively reduce pesticides from aqueous solutions, but, DLLME method is suggested to has higher priority due to the very short separation time.