Research article Synthesis and characterization of a molecularly imprinted polymer for the isolation of the 16 US-EPA priority polycyclic aromatic hydrocarbons (PAHs) in solution Somandla Ncube a , Phumlile Kunene a , Nikita T. Tavengwa a, b , Hlanganani Tutu a , Heidi Richards a , Ewa Cukrowska a , Luke Chimuka a, * a Molecular Sciences Institute, School of Chemistry, University of Witwatersrand, Private Bag X3, Johannesburg, 2050, South Africa b Department of Chemistry, University of Venda, Private Bag X5050, Thohoyandou, 0950, South Africa article info Article history: Received 31 March 2017 Received in revised form 9 May 2017 Accepted 13 May 2017 Keywords: Polycyclic aromatic hydrocarbons Molecular imprinting technology Molecularly imprinted polymers Benzo[k]fluoranthene Indeno[1 2 3-cd]pyrene abstract A smart sorbent consisting of benzo[k]fluoranthene-imprinted and indeno[1 2 3-cd]pyrene-imprinted polymers mixed at 1:1 (w/w) was successfully screened from several cavity-tuning experiments and used in the isolation of polycyclic aromatic hydrocarbons from spiked solution. The polymer mixture showed high cross selectivity and affinity towards all the 16 US-EPA priority polycyclic aromatic hy- drocarbons. The average extraction efficiency from a cyclohexane solution was 65 ± 13.3% (n ¼ 16, SD). Batch adsorption and kinetic studies confirmed that the binding of polycyclic aromatic hydrocarbons onto the polymer particles resulted in formation of a monolayer and that the binding process was the rate limiting step. The imprinted polymer performance studies confirmed that the synthesized polymer had an imprinting efficiency of 103.9 ± 3.91% (n ¼ 3, SD). A comparison of the theoretical number of cavities and the experimental binding capacity showed that the overall extent of occupation of the imprinted cavities in the presence of excess polycyclic aromatic hydrocarbons was 128 ± 6.45% (n ¼ 3, SD). The loss of selectivity was estimated at 2.9% with every elution cycle indicating that the polymer can be re-used several times with limited loss of selectivity and sensitivity. The polymer combination has shown to be an effective adsorbent that can be used to isolate all the 16 US-EPA priority polycyclic ar- omatic hydrocarbons in solution. © 2017 Elsevier Ltd. All rights reserved. 1. Literature review Polycyclic aromatic hydrocarbons (PAHs) belong to an impor- tant class of persistent organic pollutants that are commonly found in the environment at low concentrations. In urban areas, the source of PAHs includes household human and chemical waste, automobile exhaust products, storm water run-off from both impervious and pervious areas like roads, parking areas and con- struction sites, industrial effluents from the manufacture of chemicals and carbonaceous waste incineration. They then enter the wastewater treatment plants through the sewerage (Zorpas et al., 2011; Cai et al., 2007; Singh and Agrawal, 2008). The gen- eral adverse effects of PAHs to the environment and humans is widely documented (Abdel-Shafy and Mansour, 2015; Maliszewska-Kordybach, 1999; Dean and Suess, 1985). Environ- mental and potential carcinogenic health concerns of PAHs have necessitated their inclusion in lists of priority pollutants by several regulatory agencies such as the US Environmental Protection Agency (US-EPA), European Union Environmental Protection Agency, and Environment Canada. The US-EPA has identified 16 unsubstituted PAHs as priority pollutants, some of which are considered possible or probable human carcinogens (Shailaja and D'Silva, 2003). Most of the techniques used in the extraction of PAHs are fol- lowed by a clean-up step in which the PAHs are isolated from the matrix effects and finally pre-concentrated for detectability in chromatographic instruments (Rawa-Adkonis et al., 2006). This step is almost always through solid phase extraction (SPE) or gel permeation chromatography (GPC) with various adsorbent phases such as octadecyl (C 18 ) and molecularly imprinted polymers (MIPs) while membrane-based extractions like membrane assisted solid extraction and liquid phase micro extractions have been used * Corresponding author. E-mail address: luke.chimuka@wits.ac.za (L. Chimuka). Contents lists available at ScienceDirect Journal of Environmental Management journal homepage: www.elsevier.com/locate/jenvman http://dx.doi.org/10.1016/j.jenvman.2017.05.041 0301-4797/© 2017 Elsevier Ltd. All rights reserved. Journal of Environmental Management 199 (2017) 192e200