Preparation of morphology-controllable PGMA-DVB microspheres by introducing Span 80 into seed emulsion polymerization

Preparation and modification of PS-PMMA microspheres and their application in high performance liquid chromatography

Polymer microspheres have been widely used as a stationary phase for liquid chromatography. In this work, we prepared and synthesized polystyrene-methyl methacrylate (PS-PMMA) microspheres, modified them, characterized the microspheres to have good chromatographic properties, and then used them as a high-performance liquid chromatography (HPLC) stationary phase to explore their applications. First, the PS-PMMA microspheres were hydrolyzed, and the separation of benzene homologues/alkaloids was explored. Then, on the basis of hydrolysis, diazo resin (DR) was used as a coupling agent to further modify the surface of the microspheres with amphoteric glycopeptide vancomycin. The modified microspheres were used as a HPLC stationary phase to explore the application of the stationary phase in the separation of chiral drugs. This work is important to broaden the application of functional chiral columns for antibiotics and to expand the application of PS-PMMA microspheres in HPLC.

The Novel Polymethacrylate Based Hydrophilic Stationary Phase for Ion Chromatography

Ion chromatography is widely used as a useful and powerful tool for the analysis of anionic and cationic components found in waters and aqueous media. The performance and selectivity of ion chromatography are based on the stationary phase column packed material. In this study, it is aimed to develop new column material with quaternary ammonium functional group based on monodisperse polymeric particles for ion chromatography and to investigate their chromatographic performance. For the analysis of inorganic anions by ion chromatography, new stationary phases macroporous monodisperse particles based on 3-chloro-2-hydroxy propylmethacrylate-co-ethylene dimethacrylate are obtained as column packing material. 3-chloro-2-hydroxy propylmethacrylate and ethylene glycol dimethacrylate are transformed to porous monodisperse particle form by using glycidyl methacrylate as the seed latex and ethyl benzene as the porogen solvent via micro-suspension polymerization technique. Then macroporous monodisperse particles surface is functionalized by triethylamine so strong anion exchange is obtained for ion chromatography packing material. A series of stationary phases prepared from polymer particles containing different amounts of porogen solvent were tested. The results show that column packing material is successful to separate inorganic anions mixture such as F−, Cl−, NO2−, Br−, NO3− by using the carbonate and bicarbonate solutions as mobile phases.

Smart gating porous particles as new carriers for drug delivery

The design of smart drug delivery carriers has recently attracted great attention in the biomedical field. Smart carriers can specifically respond to physical and chemical changes in their environment, such as temperature, photoirradiation, ultrasound, magnetic field, pH, redox species, and biomolecules. This review summarizes recent advances in the integration of porous particles and stimuli-responsive gatekeepers for effective drug delivery. Their unique structural properties play an important role in facilitating the diffusion of drug molecules and cell attachment. Various techniques for fabricating porous materials, with their major advantages and limitations, are summarized. Smart gatekeepers provide advanced functions such as "open-close" switching by functionalized stimuli-responsive polymers on a particle's pores. These controlled delivery systems enable drugs to be targeted at specific rates, time programs, and sites of the human body. The gate structures, gating mechanisms, and controlled release mechanisms of each trigger are detailed. Current ongoing research and future trends in targeted drug delivery, tissue engineering, and regenerative medicine applications are highlighted.

A review of the design of packing materials for ion chromatography

The development of ion chromatography has made remarkable progress in the past few decades, and it is now widely used for the analysis of common ions and organic compounds. Ion chromatography has many advantages, such as fast, high sensitivity, good selectivity and support for simultaneous analysis of multiple ionic compounds. In order to meet the high requirements of material analysis, new packing materials for ion chromatography with higher sensitivity and selectivity have been developed. In this paper, a lot of knowledge of ion chromatography is reviewed, and the development of ion chromatographic packings in recent years, especially in the last five years, is summarized.

Enhancing the mechanical and thermal properties of waterborne polyurethane composites with thermoset epoxy resin microspheres

A facile way to prepare WPU with good mechanical and thermal properties by adding epoxy microspheres.

Petroleum hydrocarbon release behavior study in oil-sediment aggregates: turbulence intensity and chemical dispersion effect

This study investigated the effects of turbulence and oil dispersants on release of petroleum hydrocarbons in oil-sediment aggregates. A kinetic study showed that the static oil release process could be fitted to the first-order kinetics model. The oil concentration increased with increasing temperature and salinity, while remaining independent of pH. The dispersant desorption ability of petroleum hydrocarbons followed the sequence of: Tween 80 > Tween 85 > Span 80 > DOSS. In the presence of turbulence, the maximum release ratio was 40.28%. However, the combination of dispersants and turbulence had a smaller effect than turbulence alone. Furthermore, residual n-alkanes and PAHs in the sediments were analyzed. The results showed higher proportions of C₁₅–C₃₅ and 2–3 ring PAHs in residual oil. These results can help assess the fate and distribution of oil spills in marine environments.

This study investigated the effects of turbulence and oil dispersants on release of petroleum hydrocarbons in oil-sediment aggregates.