Reference type: Journal
Authors: Mudiam MKR, Chauhan A, Singh KP, Gupta SK, Jain R, Ch R, Murthy RC
Article Title: Determination of t,t-muconic acid in urine samples using a molecular imprinted polymer combined with simultaneous ethyl chloroformate derivatization and pre-concentration by dispersive liquid-liquid microextraction.
Publication date: 2013
Journal: Analytical and Bioanalytical Chemistry
Volume: 405
Issue: (1)
Page numbers: 341-349.
DOI: 10.1007/s00216-012-6474-9

Abstract: The present communication describes the preparation and evaluation of a molecularly imprinted polymer (MIP) as a solid-phase extraction (SPE) sorbent and simultaneous ethyl chloroformate (ECF) derivatization and pre-concentration by dispersive liquid-liquid microextraction (DLLME) for the analysis of t,t-muconic acid ( t,t-MA) in urine samples using gas chromatography-mass spectrometry. The imprinting polymer was prepared using methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2-azobisisobutyronitrile as the initiator and t,t-MA as a template molecule. The imprinted polymer was evaluated for its use as a SPE sorbent by comparing both imprinted and non-imprinted polymers in terms of the recovery of t , t -MA from urine samples. Molecular modelling studies were performed in order to estimate the binding energy and efficiency of the MIP complex formed between the monomer and the t,t-MA. Various factors that can affect the extraction efficiency of MIP, such as the loading, washing and eluting conditions, were optimized; other factors that can affect the derivatization and DLLME pre-concentration were also optimized. MIP in combination with ECF derivatization and DLLME pre-concentration for t,t-MA exhibits good linearity, ranging from 0.125 to 2 μg mL-1 ( R2 = 0.9971), with limit of detection of 0.037 μg mL-1 and limit of quantification of 0.109 μg mL-1 . Intra- and inter-day precision was found to be <6 %. The proposed method has been proven to be effective and sensitive for the selective pre-concentration and determination of t,t-MA in urine samples of cigarette smokers
Template and target information: t,t-muconic acid, t,t-MA
Author keywords: Muconic acid, Molecularly imprinted polymers, Gas chromatography-mass spectrometry, molecular modelling, Ethyl chloroformate, Dispersive liquid-liquid microextraction