The development of effective methods of enzyme stabilization is key for the evolution of biocatalytic processes. An interesting approach combines the stabilization process of proteins in ionic liquids and the immobilization of the active phase on the solid support. As a result, stable, active and heterogeneous biocatalysts are obtained. There are several benefits associated with heterogeneous processes, as easy separation of the biocatalyst from the reaction mixture and the possibility of recycling. Accordingly, this work focused on the supported ionic liquid phases as the efficient enzyme stabilization carriers, and their application in both continuous flow and batch biocatalytic processes.

A novel, efficient extraction procedure based on natural deep eutectic solvents (NADES) and ionic liquids (ILs) for determination of 20-hydroxyecdysone (20-E) in spinach has been developed. NADES, the first green extraction agent, with different hydrogen bond donors and acceptors are screened in order to determine extraction efficiencies. NADES consisting of lactic acid and levulinic acid at a molar ratio of 1:1 exhibits the highest yields. ILs, the second green extraction agent, with various cations and anions are also investigated, where [TEA] [OAc]·AcOH, χAcOH = 0.75 displays the highest recovery. Moreover, NADES-SLE and IL-SLE (SLE, solid-liquid extraction) parameters are investigated. Using the obtained optimized method, the recoveries of the target compound in spinach are above 93% and 88% for NADES-SLE and IL-SLE procedure, respectively. The methods display good linearity within the range of 0.5–30 μg/g and LODs of 0.17 µg/g. The proposed NADES-SLE-UHPLC-UV and IL-SLE-UHPLC-UV procedures can be applied to the analysis of 20-E in real spinach samples, making it a potentially promising technique for food matrix. The main advantage of this study is the superior efficiency of the new, green extraction solvents, which results in a significant reduction of extraction time and solvents as compared to those in the literature.

Supported ionic liquid phases offer several advantages related with catalysis. Immobilization of ionic liquid on the solid support provides catalytic activity or efficient matrix for active phases, as enzymes or metal compounds. Ionic liquid can be physically adsorbed on the carrier (supported ionic liquid phase) or chemically grafted to the material surface (supported ionic liquid-like phase). The use of supported ionic liquid phases improves mass transport, reduces ionic amount in the process and, most importantly, enables effortless catalyst separation and recycling. Moreover, chemical modification of the surface material with ionic liquid prevents its leaching, enhancing length of catalyst life. Silica-based materials have become an effective and powerful matrix for supported ionic liquid-like phase due to its cost-efficiency, presence of hydroxyl groups on the surface enabling its functionalization, and specific material properties, such as the size and shapes of the pores. For these reasons, supported ionic liquid-like phase silica-based materials are successfully used in the organic catalysis.

Due to a high increase in electromagnetic pollution, the protection from non-ionizing electromagnetic radiation (EMR) represents an important problem of contemporary environmental science. We are searching for natural materials with the potential for EMR screening. We have discovered that hydro-halloysite has interesting properties as an EMR absorber. Unfortunately, it is a very unstable material. Drying it for even a short period of time leads to the loss of desired properties. In the paper, we have demonstrated that the intercalation of halloysite (the process of introducing guest molecules into the mineral structure) makes it possible to recover the ability to absorb an electromagnetic wave and obtain a promising material for electromagnetic field shielding applications.

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