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SPR sensor used for amitrole detection was prepared without using any modification. Molecularly imprinted SPR sensor enabled high selectivity for amitrole pesticide. Amino acid-based functional monomer MATrp was integrated as a recognition element. Tailor-made SPR sensor enables real-time monitoring of amitrole pesticide. Synthetic recognition sites provided by MATrp were prepared without labeling.Herein, a surface plasmon resonance (SPR)-based nanosensor was fabricated using molecular imprinting technique for the selective and sensitive detection of amitrole, a commonly used highly toxic pesticide. For this purpose, polymeric nanofilms involving N-methacryloyl-l-tryptophan methyl ester and ethylene glycol dimethacrylate which are functional monomer and cross-linker, respectively, were prepared on the SPR chips surface via the ultravoilet polymerization method. The nanofilms were characterized by several techniques such as ellipsometry, Fourier transform infrared-attenuated total reflection, atomic force microscope and contact angle measurements. The kinetic analyses for amitrole detection were examined through amitrole-imprinted and non-imprinted SPR sensor chips. The developed imprinted sensor showed high selectivity to the amitrole molecule than similar molecules and a good linear relationship for the 0.06-11.90 nM concentration range with a low limit of detection value of 0.037 nM. The high imprinting efficiency (I.F: 62.38) of the amitrole-imprinted SPR sensor was determined by comparing it with the non-imprinted SPR sensor. The most suitable model of this sensor is the Langmuir adsorption model. To statistically assess the reusability of the sensor, intraday experiments were tested three times with five replicates. The relative standard deviation% value less than1.5 indicates high reproducibility for both sensor production and reproducibility of the method. The prepared sensor was also applied efficiently for the selective detection of the amitrole in spiked samples prepared from vegetables to evaluate the matrix effect. As a result, amitrole-imprinted SPR sensors have been estimated to be highly selective, fast responsive, easy to use, reusable and sensitive in detecting amitrole in both natural source and aqueous solutions. Label-free amitrole detection was performed by an aminoacid-based SPR sensor fabricated without the need for complex coupling processes.

Molecularly imprinted polymers are used for creating a specific cavity and selective recognition sites for the structure of a target molecule in a polymeric structure. In this study, specific molecularly imprinted cryogel cartridges were synthesized using two distinct functional monomers to compare imprinting efficiency for the selective recognition of Tyrosine (Tyr). Tyr-imprinted cryogel cartridge (MIP1) was prepared using metal-chelate coordination for the imprinting process by free-radical bulk polymerization under frozen conditions, and Tyr-imprinted cryogel cartridge (MIP2) was prepared in the same way using hydrophobic effects for imprinting. After the characterization of the cryogel cartridges was carried out, the optimum adsorption conditions of both were determined according to the different parameters such as flow rate (0.5-2.5 ml/min), pH of the medium (4.0-8.0), initial Tyr concentration (0.1-3.0 mg/ml), and temperature (4-45°C). Selectivity experiments of Tyr-imprinted and non-imprinted cryogel cartridges were carried out by using phenylalanine, tryptophan, and cysteine. Besides, the eluted Tyr from MIP1 and MIP2 cryogel cartridge were applied to FPLC system. Also, the reusability experiments of Tyr-imprinted cryogel cartridges was observed no significant decrease in the adsorption capacity.