Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $22,000 Total Non-Federal Funds: $44,754
Principal Investigators: Maria Fidalgo, Chung-Ho Lin
Abstract: Many man-made chemicals for agricultural use are now widely dispersed and contaminate the environment. Some of these chemicals have significant potential to interfere with normal biological functions and cause adverse effects. Concerns over chemicals that disrupt the endocrine system in humans and wildlife have grown during the last two decades, leading to efforts to screen and test for endocrine disrupting chemicals, or EDCs. In 1996 congress passed the Food Quality and Protection Act that mandated the United States Environmental Protection Agency (USEPA) develop screening and testing methods to detect environmental chemicals that interfere with the endocrine system. There is now a tremendous body of literature describing the highly significant negative impacts on the human body from EDC exposure. In fact, the Endocrine Society recently published a position statement Results from animal models, human clinical observations, and epidemiological studies converge to implicate EDCs as a significant concern to public health. Adverse reproductive health outcomes associated with EDC exposures are well documented, with reported effects on reproductive organs, body weight, puberty, and fertility. Unfortunately, conventional methods to detect organic compounds involve not only expensive instrumentation, but also a large number of separating analytical procedures, resulting in a complex, time-consuming, and laborious screening procedure. For these reasons, the development of novel approaches for easy and rapid detection of selected organic contaminants is highly desirable. Molecular imprinting is a well-established technique used to synthesize molecularly imprinted polymers (MIPs) with specific molecular recognition nanocavities. Recently, researchers have developed an original procedure that combines molecular imprinting and colloidal crystal to prepare polymers with 3D, highly ordered, macroporous structures (inverse opals) and specific binding nanocavities for a rapid assay to detect organics in water. The high sensitivity and specificity observed in these polymeric systems is mainly due to the high surface-to-volume ratios of the structure that allow for a more efficient mass transport in submicrometer-sized pores and enhance surface reactions. The combination of molecular imprinting techniques and photonic crystals derived from the self-assembly of silica nanoparticles used as templates allows for the optical detection of adsorption trace compounds due to changes of the wavelength at maximum intensity of the Bragg diffraction peak. This project will involve developing a highly sensitive and specific sensor based on a MIP array capable of simultaneously detecting total EDC concentration. To this end, porous MIP films will be fabricated and characterized from colloidal crystal templates; it will explore the selectivity and specificity of MIPs, and the potential interferences of structural analogues as well as natural water chemistry, characterized by natural organic matter and/or dissolved substances. Furthermore, the kinetics of contaminant attachment to the MIP films, as well as release conditions and mechanisms will be investigated. The combination of molecular imprinting techniques and photonic crystals allows for the optical detection of adsorption trace compounds due to changes of the wavelength at maximum intensity of the Bragg diffraction peak.