title: Detection of 17β-estradiol in water samples by a novel double-layer molecularly imprinted film-based biosensor.
abstract: This study reports a novel double-layer molecularly imprinted film (MIF)-based biosensor for rapid, sensitive and highly selective detection of small molecule 17β-estradiol (E2) that is frequently detected in environmental water samples. In this system, the modification of gold surface of SPR chip was performed by 1-dodecanethiol. Then double-layer MIF was generated on the 1-dodecanethiol modified gold surface. The non-modified and imprinted surfaces were characterized by atomic force microscopy (AFM), scanning electron microscope (SEM) and contact angle measurements. Analysis of surface plasmon resonance (SPR) spectroscopy showed that the imprinted sensing film displayed good selectivity for E2 compared to other analog molecules and NIF. A good linear relationship was obtained between the SPR angle and E2 concentrations over a range of 2.50×10(-13)-2.50×10(-)(9)mol/L (R(2)=0.993) with the lowest measurable concentration of 2.50×10(-13)mol/L. The sensor can be regenerated with the mixture of acetic acid and PBS buffer (v/v=1:9) as a desorption agent over tens of times without significant deterioration of the sensor performance. Potential interference of real environmental sample matrix was assessed by spiked samples in several waste seawater effluents. This portable sensor system can be successfully applied for on-site real-time inexpensive and easy-to-use monitoring of E2 or other small molecule pollutants in environmental samples such as effluents or water bodies.
authors.affiliation: Key Laboratory of Cluster Science of Ministry of Education, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Tan
authors.affiliation: Key Laboratory of Cluster Science of Ministry of Education, Beijing Institute of Technology, Beijing 100081, People's Republic of China. Electronic address: txwei@bit.edu.cn.
authors.forename: Tianxin
authors.initials: T
authors.lastname: Wei
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D004958:Estradiol / Q000032:analysis*; D057230:Limit of Detection; D018625:Microscopy, Atomic Force; D054802:Molecular Imprinting / Q000379:methods; D015203:Reproducibility of Results; D012623:Seawater / Q000032:analysis; D012680:Sensitivity and Specificity; D013438:Sulfhydryl Compounds / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D013438:Sulfhydryl Compounds; D014874:Water Pollutants, Chemical; C013976:dodecylmercaptan; D004958:Estradiol
keywords: 17β-Estradiol; Double-layer MIF; Surface plasmon resonance (SPR)