Development of dieldrin, endosulfan, and hexachlorobenzene-imprinted polymers for dye-displacement array sensing Ofelia V. Silverio, 1,2 Regina C. So, 1 Katrina Jean S. Elnar, 1 Christian A. Malapit, 1 Ma. Cristine M. Nepomuceno 1 1 Department of Chemistry, Ateneo de Manila University, School of Science and Engineering, Loyola Heights, Quezon City, 1108 Philippines 2 Bulacan Agricultural State College, Pinaod, San Ildefonso, Bulacan, 3010 Philippines Correspondence to: R. C. So (E-mail: rso@ateneo.edu or regcso0@gmail.com) ABSTRACT: Due to the toxicity associated with the exposure to organochlorine pesticides, new materials capable of selectively captur- ing and detecting these compounds are highly desirable. In this study, imprinted polymers were prepared using three organochlorine pesticides—dieldrin (DE), endosulfan (EN), or hexachlorobenzene (HCB) as templates. The MIPs were polymerized via precipitation polymerization. The yields were over 90% with particle sizes ranging from 62 to 214 nm. Binding studies combined with GC-ECD analysis showed that each template is more selective to its corresponding MIP compared with the other two structurally homologous templates. These results were consistent with those obtained using UV–vis where more bromocresol green (BCG) dye was released when higher template concentrations were introduced to the corresponding BCG-impregnated MIPs. Since unique selectivity response pattern for each of the MIPs was obtained, this demonstrated that the MIPs were selective and can be potentially used in dye- displacement array sensing. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44401. KEYWORDS: adsorption; molecular recognition; nanoparticles; porous materials Received 13 March 2016; accepted 20 August 2016 DOI: 10.1002/app.44401 INTRODUCTION Among the different agricultural pollutants, organochlorines constitute a significant fraction of these hazardous compounds released into the environment. Organochlorines do not readily degrade and these compounds can accumulate in biological, ter- restrial, and groundwater systems. Endosulfan is a broad- spectrum insecticide and acaricide which kills both beneficial and unwanted insects. 1 It has been banned in several countries because of its toxicity and endocrine disrupting properties. 2 Dieldrin is also a toxic insecticide and has been shown to cause estrogenic effects. 3 Hexachlorobenzene is a banned fungicide due to the hazards associated upon oral or dermal contact and the anticipated carcinogenic properties. 4 Studies have been conducted in understanding macro-scale environmental phenomena and in the development of technolo- gies for monitoring pollutants. 5,6 Most of these technologies uti- lized analytical techniques for the rapid determination of organochlorine/pesticide residues, these include: gas chromatog- raphy in tandem with atomic emission detection (GC-AED), 7,8 gas chromatography-mass spectrometry (GC-MS), 5,9 high performance liquid chromatography with mass spectrometry (LCMS) or diode array detection (LC-DAD), 10–12 and others. 13 These techniques have excellent sensitivity but involved costly laboratory equipment or trained operators in carrying out the analysis. Since organochlorines are present in the environment in trace amounts, nanotechnology provides new ways to determine and sequester these contaminants. 14,15 In particular, molecular imprinting technology allowed the production of synthetic materials with template recognition properties similar to that of a natural enzyme–substrate system. This capability, together with low cost, ease of preparation, long shelf life, and superior stability over their natural receptor counterparts make molecu- larly imprinted polymers (MIPs) an attractive choice for extrac- tion and biological and chemical sensing. 16–19 Typically, MIPs are produced by self-assembly of the template and functional monomers, forming a pre-polymerization com- plex. The complex is then polymerized in the presence of excess amount of crosslinking agent. The resulting crosslinked polymer matrix is highly rigid and preserves the structure of the Additional Supporting Information may be found in the online version of this article. V C 2016 Wiley Periodicals, Inc. WWW.MATERIALSVIEWS.COM J. APPL. POLYM. SCI. 2017, DOI: 10.1002/APP.44401 44401 (1 of 11)