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Novel hybrid NaA/xanthan gum (XG)–alginate composites were prepared by controlling zeolite NaA dispersion into calcium ion cross-linked binary XG–alginate hydrogel. Pre-modification of zeolite NaA by natural XG facilitated the particle dispersion since XG moieties tended to interact with zeolite preventing particle agglomeration. Binary combination of alginate and XG contributed to abundant multi-dimensional features of the composites. Entrapped zeolites reinforced the operation stability of the composites. X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, mercury intrusion porosimetry, etc. were utilized for characterization of the composites. Removal of Co 2+ and Ni 2+ was studied in a batch mode. The best pH condition for the sorption is 6.0. The sorption could be well described by Langmuir isotherm and maximum sorption capacities of Co 2+ and Ni 2+ were at 43.9 and 81.3 mg g − 1 (323 K) respectively. The kinetics of sorption followed pseudo-second order equation. NaA/XG–alginate composite would be a promising candidate for sorptive removal Co 2+ and Ni 2+ from nuclear wastewater.

In this study, heteroatomic ferrisilicalite-1 zeolite monolith (FS-1 ZM) was developed for affinitive recognition of intracellular phosphorylated protein in Tetrahymena thermophila after exposure to organoarsenic feed additives (roxarsone, ROX; p-arsanilic acid, PASA) and their photodegradates. ROX or PASA can be photodegradated into toxic inorganic arsenicals, which has become a public concern. After T. thermophila being exposed to ROX or PASA and their photodegradates, it is of significance to address intracellular protein phosphorylation alteration. However, it is challenging for effective capture of phosphorylated protein under the interference of arsenicals uptake. Followed by ferrisilicalite-1 zeolite monolith based immobilization process, sodium dodecyl sulfate–polyacrylamide electrophoresis, in-gel enzymatic digestion, and subsequent LC–MS/MS methodology, the integrated protocol was firstly attempted for identification of arsenic-induced phosphorylated protein alteration. It was found there was little impact of ROX or PASA on intracellular phosphorylated protein distribution. Alternatively, phosphorylated 14-3-3ϵ was down-regulated after the cells were exposed to photodegradates of ROX or PASA, which were similar to those following exposure to inorganic arsenicals. Overall, inorganic arsenicals present during the degradative pathways of ROX or PASA affect the signal transduction system of T. thermophila cells. The down-regulation of phosphorylated 14-3-3ϵ would be further studied as potential biomarker for organoarsenicals released into the environment.

The originally fabricated phytase/HHFeZ bio-conjugates could appropriately enhance enzyme stabilization after heteroatomic hierarchical Fe-ZSM-5 zeolite (HHFeZ) was developed as a novel matrix for affinitive immobilization of Escherichia coli (E. coli) phytase. The immobilization strategy was primarily dependent on the affinitive coordination between heteroatomic iron atoms anchored into the HHFeZ frameworks with multiple sites of phosphorylation in phytase. In addition, the ordered multiporous structures of HHFeZ contributed to phytase immobilization and stabilization. The conditions for phytase immobilization were optimized under a solution pH of 4.5 in a batch mode, and the maximum phytase immobilization capacity was determined to be 2.01 mg mg−1. Compared to those of free phytase, the thermal and proteolytic resistance of phytase/HHFeZ bio-conjugates were effectively improved, and the enzymatic activity was maintained over a broad pH range. The phytase/HHFeZ bio-conjugates would be an innovative choice for eco-sustainable exploitation and utilization of phytate-phosphorus, especially with respect to eutrophication control.

A hierarchical Fe-ZSM-5 zeolite monolithic column was fabricated for immobilization of low abundance phosphoprotein through specific coordination between heteroatomic Fe in the framework of the zeolite with the phosphate group in the micro-environment of the protein. Compared to traditionally immobilized metal ion chromatography, this method could be directly manipulated and handily adapted for phosphoproteomics identification.