TY - JOUR AU - Madikizela, Lawrence Mzukisi AU - Zunngu, Silindile Senamile AU - Mlunguza, Nomchenge Yamkelani AU - Tavengwa, Nikita Tawanda AU - Mdluli, Phumlane Selby AU - Chimuka, Luke PY - 2018/07/31 Y2 - 2024/03/29 TI - Application of molecularly imprinted polymer designed for the selective extraction of ketoprofen from wastewater JF - Water SA JA - WSA VL - 44 IS - 3 July SE - Research paper DO - 10.4314/wsa.v44i3.08 UR - https://watersa.net/article/view/6615 SP - AB - <p>A molecularly imprinted polymer (MIP) that is selective to ketoprofen was synthesized and applied in the adsorption of the&nbsp;target compound from water. The MIP was synthesized using a bulk polymerization method at high temperatures (60–80°C),&nbsp;where ketoprofen, 2-vinylpyridine, ethylene glycol dimethacrylate, toluene and 1,1´-azobis(cyclohexanecarbonitrile) were&nbsp;used as template, functional monomer, cross-linker, porogen and initiator, respectively. Non-imprinted polymer (NIP)&nbsp;was synthesized similarly to the MIP but in the absence of ketoprofen. From molecular dynamics simulation, the nature of&nbsp;interactions that occurred between the template and the functional monomer were found to be based on hydrogen bonding.&nbsp;This was confirmed experimentally, where a high extraction efficiency of ≥ 90% was obtained at acidic conditions (pH 5)&nbsp;due to the protonation of ketoprofen. A contact time of 45 min was sufficient for the maximum adsorption of ketoprofen&nbsp;from 10 mL spiked water using 8 mg of the adsorbent. MIP showed greater selectivity than NIP by achieving a relative&nbsp;selectivity coefficient of 7.7 towards ketoprofen in the presence of structurally related pharmaceuticals. Furthermore, the&nbsp;order of sorption onto the MIPs from water was ketoprofen &gt; fenoprofen &gt; gemfibrozil. From a modelling perspective, the&nbsp;Langmuir adsorption isotherm and pseudo-second-order kinetic model gave the best fit, with maximum adsorption capacity&nbsp;of 8.24 mg·g<sup>−1</sup> and sorption rate constant of 0.25 mg·g<sup>−1</sup>·min<sup>−1</sup> for MIP. This was translated to chemisorption of ketoprofen onto&nbsp;the homogeneous MIP binding sites. This work demonstrated the great potential of MIP in selective recognition of ketoprofen from wastewater relative to closely related compounds.</p> ER -