Concentration dependent atrazine–atrazine complex formation promotes selectivity in atrazine imprinted polymers

Abstract

An atrazine (ATR) molecularly imprinted polymer (MIP) was prepared using a non-covalent strategy. The affinity and selectivity of the polymer was initially evaluated under non-equilibrium conditions and the polymer was shown to possess good template selectivity. The selectivity of the polymer was further investigated under equilibrium conditions and over a range of concentrations using Scatchard plots and Hill plots and by assessing distribution coefficients and normalised selectivity values. It was observed that both selectivity and affinity were dependent on the concentration of the ligand and that unusually selectivity and affinity were better at higher atrazine concentrations. It was concluded that this phenomenon resulted from the formation of atrazine-atrazine complexes during the pre-polymerisation stage and during rebinding and that the polymer demonstrated improved atrazine affinity when the conditions favoured complex formation.

Lithographically patterned molecularly imprinted polymer for gravimetric detection of trace atrazine

“…To fabricate MIPs for atrazine detection, methacrylic acid (MAA) [or methyl methacrylate (MMA)], ethylene glycol dimethacrylate (EGDMA), and 2,2 -azobis(2-isobutyronitrile) (AIBN) have been used for two common methods in the synthesis of imprinted polymers, i.e. UV(or IR)-initiated [22,23] and thermal polymerization [24,25]. However, the UV-initiated polymerization reaction has been mostly performed due to relatively short-period reaction process.…”

Optimization of solid-phase extraction using developed modern sorbent for trace determination of ametryn in environmental matrices

“…This Table 9 The effect of amount of 0.1 M hydrochloric acid on the ametryn recovery (%). phenomenon has been previously shown [42] for atrazine, where it was proposed that, at higher concentrations the ability of atrazine to generate atrazine-atrazine complexes, both in solution and on the polymer surface, results in increased atrazine selectivity. In order to evaluate the effect of sample volume on the MISPE performance, different volume of sample ranged from 5 to 15 mL as mentioned in Table 4 was prepared using deionized water.…”

“…Usually the specificity of the ametryn MIP is determined via the cross-reactivity of several triazine herbicides (high or intermediate cross-reactivity) and some other pesticide compounds (low cross-reactivity) [43]. Based on the obtained results from Table 10 and similar to another work [42], atrazine, simazine, cyanazine and propazine are structurally similar and it was therefore unsurprising that their recoveries on the ametryn imprinted column were similar. The minor variation in recoveries observed can be accounted for by small variations in the interaction energies between the molecules and the recognition sites of the polymer [31], size, and the additional methyl substitution.…”

Molecularly imprinted nanopatterns for the recognition of biological warfare agent ricin

“…Moreover, MIPs are also used for many purposes such as adsorption of 17␤-estradiol (Wei and Mizaikoff, 2007), reflectometric interference spectroscopic sensing of atrazine (Belmont et al, 2007), separation of ephedrine enantiomers (Guerreiro et al, 2008), hanging mercury drop MIP modified electrode for differential pulse cathodic stripping voltammetric analysis of creatine (Lakshmi et al, 2007), fructosyl valine recognition (Rajkumar et al, 2007), solid phase extraction of photosynthesisinhibiting herbicides (Breton et al, 2007), biorecognition solvent extraction agents (Castell et al, 2006), recognition of atrazine (Lavignac et al, 2006), fabrication of bilirubin-specific sensor (Huang et al, 2007), adsorption study of dansylated amino acids by surface plasmon resonance (Li and Husson, 2006), cholesterol recognition (Boonpangrak et al, 2006), recognition of copper (Baghel et al, 2007) recognition of chemical warfare agent sulfur mustard (Boopathi et al, 2006), recognition of ochratoxin A (Turner et al, 2004) and also in catalysing a trans esterification process (Meng et al, 2004).…”