Atrazine imprinting

Kubo A, Shinmori H, Takeuchi T (2006). Atrazine-imprinted microspheres prepared using a microfluidic device. Chem Lett 35 588-589... 

The first work in this field was probably that of Piletsky et al. [84] that described a competitive FILA for the analysis of triazine using the fluorescent derivative 5-[(4,6-dichlorotriazin-2-yl)amino]fluorescein. The fluorescence of the supernatant after incubation was proportional to the triazine concentration and the assay was selective to triazine over atrazine and simazine. The same fluorescent triazine derivative was applied to competitive assays using atrazine-imprinted films [70]. To this end an oxidative polymerization was performed in the presence of the template, the monomer(s) 3-thiopheneboronic acid (TBA) or mixtures of 3-amino-phenylboronic acid (APBA) and TBA (10 1) in ethanol-water (1 1 v/v) where the template is more soluble. The polymers were grafted onto the surface of polystyrene microplates. The poly-TBA polymers yielded a detection limit of 8 pM atrazine whereas for the poly-TBA-APBA plates it was lowered to 0.7 pM after 5 h of incubation. However, a 10-20% decrease in the polymer affinity was observed after 2 months. 

Fig. 13.9. Binding of the original template species in atrazine-imprinted (A) and ametryn-imprinted (B) polymers.

Figure 1. QCM sensor response of an atrazine-imprinted polyactylic acid towards a pulse of 3 ppb atrazine in water.

Fig. 6-5 Scatchard plot for the binding of atrazine by the atrazine-imprinted polymer [1]...

Using the above-described automated system, several functional monomers have been screened for the development of molecularly imprinted polymers for the herbicides atrazine and ametryn [54]. According to the results, MAA appears to be more effective for developing the affinity in the atrazine-imprinted polymers. In contrast, 2-(trifluo-romethyl)acrylic acid is more effective for ametryn imprinting. 

Fig. 9a, b. Chromatograms obtained after pre-concentration of a 100 ml groundwater sample spiked at 1 p.g 1 1 through a a CP-cartridge b a cartridge filled with a polymer imprinted with terbuthylazine. Peaks 1 = deisopropylatrazine, 2 = deethylatrazine, 3 = simazine, 4 = atrazine, 5 = propazine, 6 = terbuthylazine, I.S. = internal standard (diuron). Reprinted with permission from Ferrer I, Lanza F, Tolokan A, Horvath V, Sellergren B, Horvai G, Barcelo D (2000) Anal Chem 72 3934. Copyright 2000 American Chemical Society... 

Figure 15.11 Sensor response to herbicide concentration obtained with a polymer imprinted with atrazine. Reprinted from Sergeyeva et al. (1999). Copyright 1999 Elsevier Science.

Sergeyeva TA, Piletsky SA, Brovko AA, Slinchenko EA, Sergeeva LM, El skaya AV. Selective recognition of atrazine by molecularly imprinted polymer membranes. Development of conductometric sensor for herbicides detection. Anal Chim Acta 1999 392 105-111. 

Another nice example of nanostructuring an MIP layer is the work published by Wu et al. [138, 139] who developed a label-free optical sensor based on molecularly imprinted photonic polymers. Photonic crystals were prepared by self-assembly of silica nanospheres. The space between the spheres was then filled with MIP precursor solution. After polymerization, the silica was dissolved, leaving an MIP in the form of a 3D-ordered interconnected macroporous inverse polymer opal (Fig. 15). The authors were able to detect traces of the herbicide atrazine at low concentrations in aqueous solution [139]. Analyte adsorption into the binding sites resulted in a change in Bragg diffraction of the polymer characterized by a color modification (Fig. 15). 

Takeuchi et al. reported the preparation of an imprinted polymer for the conversion of the herbicide atrazine (100) in atraton (101), a less toxic compound, by conversion of an atrazine chloride into methoxy [59, 60]. After polymerisation and removal of the template, analysis of the imprinted polymer showed saturation kinetics, suggesting an enzyme-like behaviour of the polymer. 

Atrazine herbicide in solution MAA MIP-based competitive inhibition assay (molecularly imprinted sorbent assay) 1 ug/ml Muldoon and Stanker, 1995... 

MATSUI J, MIYOSHIY, doblhoff-dier o and TAKEUCHIT (1995), A molecularly imprinted synthetic polymer receptor selective for atrazine , Anal Chem,... 

MULDOON M T and STANKER L H (1997), Molecularly imprinted solid phase extraction of atrazine from beef liver extracts , Anal Chem, 69, 803. 

PTT.F.TSKY S A, PILETSKAYA E V, ELGERSMA A V, YANO K and KARUBE I (1995), Atrazine sensing by molecularly imprinted membranes , Biosens Bioelectro, 10, 959-964. 

Muldoon, M.T. and L.H. Stanker (1995). Polymer synthesis and characterization of a molecularly imprinted sorbent assay for atrazine. J. Agric. Food Chem., 43 1424-1427. 

Shoji, R., T. Takeuchi, and I. Kubo (2003). Atrazine sensor based on molecularly imprinted polymer-modified gold electrode. Anal. Chem., 75(18) 4882-4886. 

Siemann, M., L.I. Andersson, and K. Mosbach (1996). Selective recognition of the herbicide atrazine by noncovalent molecularly imprinted polymers. J. Agric. Food Chem., 44 141-145. 

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