Preparation and performance analysis of monodisperse glycidyl methacrylate modified restricted access media-imprinted materials.

Using monodisperse poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) as the matrix, and pefloxacin template molecules, a novel restricted-access medium molecularly imprinted polymers with Bovine serum albumin crosslinked on its surface was prepared through reversible addition-fragmentation chain-transfer polymerization. Then, the obtained material was employed in dispersive solid-phase extraction to analyze the fluoroquinolones in untreated egg samples by high-performance liquid chromatography-ultraviolet detection. Adsorption performance revealed a good binding amount (40.72 mg/g), fast binding kinetics (25 min), satisfactory selectivity, and good ability to eliminate matrix interference. The reusability experiments indicated the materials have good reusable performance after repetition. Under the optimized conditions, restricted access media-molecularly imprinted polymers-dispersive solid-phase extraction was combined with high-performance liquid chromatography-ultraviolet to enrich fluoroquinolones in untreated eggs, good limit of detection (1.31-3.15 µg/L) and high recovery (89.5-96.8%) were obtained. The results showed that the prepared restricted-access material is promising for the direct detection of antibiotics in complex samples.

Adsorption of cadmium ions from simulated battery wastewater by polyethylene polyamine-modified activated carbon.

The objective of this work was to study the treatment of wastewater containing cadmium ions (Cd2+). Activated carbon (AC) was modified with potassium hydroxide (KOH) and polyethylene polyamine (PEPA). The structure and morphology of the modified AC was characterized. The effect of pH on adsorption was investigated, and the binary competitive adsorption and the reusability of the modified AC were studied. Subsequently the modified AC was used as an adsorbent for the removal of Cd2+ from wastewater. The adsorption capacity of optimized modified AC was 9.7 times that of unmodified AC. Kinetic adsorption curves were in accordance with pseudo-second-order kinetics, and the isothermal curves were in accordance with the Langmuir equation. The results indicate that the AC has potential in the treatment of the wastewater containing Cd2+ discharged from chemical plants during battery manufacturing.

Progress of molecular imprinting technique for enantioseparation of chiral drugs in recent ten years.

The existence of chiral compounds is a very common phenomenon in the field of medicine, and nearly 60% of drugs are chiral. The separation of racemic drugs is the key to safe use of drugs. Molecularly imprinted technique (MIT) has attracted wide attention in the separation of chiral drugs in recent years due to its simple operation and strong specific recognition ability of target molecules. Molecularly imprinted polymers (MIPs) have been used as selective adsorbents in a variety of analytical techniques, and excellent progress has been made in the separation of chiral drugs. In this paper, the MIT for the separation of drug in recent ten years is reviewed. We will introduce how to achieve chiral drug resolution in different chromatographic techniques based on the morphological differences of MIPs (micron-sized particles, nanoparticles and monolithic column materials) as the classification criteria. Furthermore, the contributions of surface molecularly imprinted technique (SMIT) and molecularly imprinted membrane (MIM) technology in racemic drug resolution are also introduced. Finally, the main application challenges of chiral MIT are briefly introduced, and the future development direction of this field is prospected.