Preparation and application of hollow molecularly imprinted polymers with a super-high selectivity to the template protein

The Impact of Processing and Extraction Methods on the Allergenicity of Targeted Protein Quantification as Well as Bioactive Peptides Derived from Egg

This review article discusses advanced extraction methods to enhance the functionality of egg-derived peptides while reducing their allergenicity. While eggs are considered a nutrient-dense food, some proteins can cause allergic reactions in susceptible individuals. Therefore, various methods have been developed to reduce the allergenicity of egg-derived proteins, such as enzymatic hydrolysis, heat treatment, and glycosylation. In addition to reducing allergenicity, advanced extraction methods can enhance the functionality of egg-derived peptides. Techniques such as membrane separation, chromatography, and electrodialysis can isolate and purify specific egg-derived peptides with desired functional properties, improving their bioactivity. Further, enzymatic hydrolysis can also break down polypeptide sequences and produce bioactive peptides with various health benefits. While liquid chromatography is the most commonly used method to obtain individual proteins for developing novel food products, several challenges are associated with optimizing extraction conditions to maximize functionality and allergenicity reduction. The article also highlights the challenges and future perspectives, including optimizing extraction conditions to maximize functionality and allergenicity reduction. The review concludes by highlighting the potential for future research in this area to improve the safety and efficacy of egg-derived peptides more broadly.

Functional Properties and Extraction Techniques of Chicken Egg White Proteins

Chicken egg whites contain hundreds of proteins, and are widely used in the food, biological and pharmaceutical industries. It is highly significant to study the separation and purification of egg white proteins. This review first describes the structures and functional properties of several major active proteins in egg whites, including ovalbumin, ovotransferrin, ovomucoid, lysozyme, ovomucin, ovomacroglobulin and avidin. Then, the common techniques (including precipitation, chromatography and membrane separation) and some novel approaches (including electrophoresis, membrane chromatography, aqueous two-phase system and molecular imprinting technology) for the separation and purification of egg white proteins broadly reported in the current research are introduced. In addition, several co-purification methods for simultaneous separation of multiple proteins from egg whites have been developed to improve raw material utilization and reduce costs. In this paper, the reported techniques in the last decade for the separation and purification of chicken egg white proteins are reviewed, discussed and prospected, aiming to provide a reference for further research on egg proteins in the future.

Hydrophilic Hollow Molecularly Imprinted Polymer Microparticles with Photo- and Thermoresponsive Template Binding and Release Properties in Aqueous Media

A facile, general, and efficient approach to prepare hydrophilic hollow molecularly imprinted polymer (MIP) microparticles with photo- and thermoresponsive template binding and release behaviors in aqueous media is described, which includes the preparation of uniform "living" silica submicrospheres bearing surface atom transfer radical polymerization (ATRP)-initiating groups (i.e., alkyl halide groups) via a one-pot sol-gel method, their subsequent grafting of azobenzene (azo)-containing MIP shell and poly(N-isopropylacrylamide)-block-poly(2-hydroxyethyl methacrylate) (PNIPAAm-b-PHEMA) brushes via successive surface-initiated ATRP, and final removal of the silica core. The successful synthesis of such hydrophilic hollow MIP microparticles was confirmed with SEM, FT-IR, water dispersion stability, and static contact angle studies. They proved to show apparently higher template binding capacities than the corresponding solid ones and obvious photo- and thermoresponsive template binding properties in aqueous solutions. Moreover, their pronounced light- and temperature-controlled template release in aqueous media was also demonstrated. In particular, the introduction of PNIPAAm-b-PHEMA brushes onto hollow MIP microparticles imparted them with high surface hydrophilicity both below and above the lower critical solution temperature of PNIPAAm, which paves the way for their applications in such areas as controlled drug/chemical delivery and smart bioanalysis.

Role of chirality and macroring in imprinted polymers with enantiodiscriminative power

Enantioselective discrimination of chiral amines is of great importance as their biological properties often differ. Therefore, here we report the development of synthetic receptors for their enantioselective recognition and pH-sensitive drug release. This paper reports the preparation of three pyridine and two benzene derivatives containing an allyloxy group [(S,S)-5, 6-9] as well as their evaluation as functional monomer anchors for chiral imprinting of amines. The enantiomeric enriching ability and controlled release of the imprinted polymers (IPs) were evaluated using racemic mixture of 1-(1-naphthyl)ethylamine hydrogen perchlorate (1). The effect of the enantiomeric purity of the template on the enantioseparation performance was investigated. Racemic template in combination with enantiomerically pure macrocyclic anchors and vice versa yields IPs with excellent enantiomeric recognition. In vitro drug delivery, enantiomeric enrichment and pH-sensitive release were investigated through kinetic models.

Monodisperse magnetic ion imprinted polymeric microparticles prepared by RAFT polymerization based on γ-Fe2O3@meso-SiO2nanospheres for selective solid-phase extraction of Cu(ii) in water samples

Utilising a general protocol for making surface-imprinted core–shell microparticlesviaa RAFT-mediated approach, we developed a Cu(ii) imprinted polymer with a novel magnetic nanosphere, γ-Fe₂O₃@meso-SiO₂, as support.