Capillary electrophoresis characterization of molecularly imprinted polymer particles in fast binding with 17β‐estradiol

Abstract

Molecularly imprinted polymer (MIP) submicron particles were synthesized, using either ethylene glycol dimethacrylate or trimethylolpropane trimethacrylate as a cross-linker, specifically for recognition of 17β-estradiol (E2). HPLC with fluorescence detection (HPLC-FD) results showed that 90(±5)% of E2 bound onto these particles after 2 min of incubation, and 96(±3)% after long equilibrium. The binding capacity was 8(±3) μmol/g for MIP particles prepared using ethylene glycol dimethacrylate, and 33-43(±8) μmol/g for using trimethylolpropane trimethacrylate. CE separation of MIP and non-imprinted polymer particles was successful when 50 mM borate buffer (pH 8.5) containing 0.005% w/v EOTrol™ LN in reverse polarity (-30 kV) was used. The electrophoretic mobilities of MIP and non-imprinted polymer particles, together with dynamic light scattering measurement of particle sizes, allowed for an estimation of their surface charges. Automated injection of E2 and particles in mixture set a lower limit of 20(±1) s on incubation time for the study of fast binding kinetics. The presence of E2 and bisphenol A (BPA) together tested the selectivity of MIP particles, when the two compounds competed for available binding cavities or sites. Addition of E2 after BPA confirmed E2 occupation of the specific binding cavities, via displacement of BPA.

A thalidomide templated molecularly imprinted polymer that promotes a biologically active chiral entity tagged in colon carcinoma cells and protein-related immune activation

“…There was not much difference in the zeta potential for the R-imprinted MIP as both formulations of the MIP showed a negative charge for the obtainable nanoparticle, while it was noticed to be a positive charge for either the S-imprinted MIPs and the RS-imprinted MIP-3 (see Table 2). The high molar ratio of the TRIM crosslinker used in the F-1 formulation produced smaller size of MIP than the F-2 and these results agreed with the findings of DeMaleki et al [21]. It was noteworthy, that the size and rate of polymerization was influenced by the early addition of the template molecule that facilitated a better complexation with the monomers in the defined monomeric reaction with respect to the charge onto the surface of the MIP.…”

Ultrasonication‐assisted synthesis of molecularly imprinted polymer‐encapsulated magnetic nanoparticles for rapid and selective removal of 17β‐estradiol from aqueous environment

“…Despite the smaller molecular mass, BPA exhibited poor binding interactions with E2‐imprinted M‐MIPs. When BPA was used as interfering or competing compound, same pattern of results was observed [14, 37, 39]. The rebinding performance of M‐MIPs further suggests the applicability of E2‐imprinted M‐MIPs for group‐specific removal of steroidal estrogens from aqueous environment.…”

Optimization of Molecularly Imprinted Polymer Method for Rapid Screening of 17β-Estradiol in Water by Fluorescence Quenching

“…A rapid method (under 10 min) has been developed for E2 determination by measuring the change in fluorescence emission intensities between these two fluorescence quenching steps, using first AuNPs and then sodium nitrite. One major advantage of this method is the high selectivity of MIP particles for E2, as previously demonstrated using molecules with similar structures (estrone, ethynylestradiol) [21] and dissimilar structures (bisphenol A) [26]. Other fluorescent molecules would not interfere with the E2 determination because they can only bind nonspecifically to be readily quenched by AuNPs.…”