a variety of applications, such as drug delivery or biocatalysis accessible. [2] In addition, mesoporous silica offers a wide variety of transport characteristics achieved by introducing organic functions into the silica framework. Those silica hybrid materials are a common motive in separation processes, drug delivery, or sensor technology. [3] Key properties, such as high specific surface area, stability, adjustable pore geometries, as well as high diversity regarding surface chemistry allow their application in such diverse areas. [4] Especially the responsive, so-called smart, organo-silica materials have been established as a new fascinating field of research over the last decades. [5] Using responsive polymers, gates are created in silica nanopores which react to triggers, such as light, [6] pH, [7] or temperature [8] and thus control pore accessibility, transport, or the release of drugs. [9] Applications for mesoporous silica strongly depend on charge generation and the corresponding gating behavior of the mesopores, which result from interactions with pH adjusted solutions.Controlled polymerization and thus precise control on pore filling and charge density in nanopores has been demonstrated by atom transfer radical polymerization, reversible additionfragmentation chain transfer, or surface initiated photoiniferter polymerization. [10] Only very recently it has been shown that not only the amount of polymer but also the architecture of the polymer chains can be controlled and block-cooligomers in pores can be generated. [10a,11] Thereby, pH responsive polymers Functionalized ordered mesoporous materials are relevant in technologies, such as drug release, sensing, and separation. To design functionality, the silica framework can be functionalized with responsive molecules or polymers. Often, the pH value in those hybrid materials determines performance. Even though pH/pKa differences between polymers in bulk solutions and nanoscale confinement have been observed, the influence of confinement on pH-and pore filling dependent polyelectrolyte oligomer chain charge has yet not been investigated systematically. Here, mesoporous silica films are functionalized with (2-dimethylamino) ethyl methacrylate) (DMAEMA) and 2-(methacryloyloxy)ethyl phosphate (MEP) oligomers using photoiniferter initiated polymerization. This approach allows a controlled and environmentally friendly mesopore functionalization in water. The obtained oligomer functionalized pores are tunable with respect to pore filling. For both, poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) and poly(2-(methacryloxy)ethyl phosphate) (PMEP), the charge generation inside mesopore confinement is significantly delayed toward harsher pH conditions resulting in pKa shifts of 1-2 pH units. Polymer amount and ionic strength show to further influence the pKa of PDMAEMA in mesopores. The technological importance of the pH value in confinement and its effect on enzyme stabilization is demonstrated. Lipase from Aspergillus oryzae loses its activity upo...

Herein, we report the formation of α‐amylase containing polyelectrolyte complexes (PECs). The method for the encapsulation of α‐amylase is based on interactions between two oppositely charged polyelectrolytes, poly(acrylic acid) (PAA) and polyethylenimine (PEI). We could show that electrostatic interactions ensure the incorporation of the enzyme into the formed polyelectrolyte complexes. The encapsulation has no negative effect on enzyme activity and protects against denaturation of the enzyme initiated by low pH values. The resulting PECs are 150–250 nm in size with narrow size distribution, appear in a spherical shape and are colloidally stable. The complexation of both polyelectrolytes and the immobilization of α‐amylase are investigated using fractionating techniques mainly the analytical ultracentrifugation and asymmetrical‐flow field‐flow fractionation. The formation of PECs represents a simple method for the encapsulation of α‐amylase without the use of organic solvents and requires no additional purifications steps. This one‐step approach, yielding high encapsulation efficiencies, shows the potential as a drug delivery system for sensitive hydrophilic actives in future. α‐amylase is immobilized in polyelectrolyte complexes made of polyethylenimine and poly(acrylic acid). Optimized encapsulation conditions and the resulting polyelectrolyte complexes are investigated via determination of IEP, α‐amylase activity assays, nanoDSC measurements, zeta potential values, dynamic light scattering, microscopy, and fractionating techniques. The encapsulated enzyme is protected against denaturation initiated by low pH values. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45036.

Herein, the synthesis of enzyme-polymer conjugates is reported. Four different activated polymers (mPEG-aldehyde, mPEG-NHS, maltodextrin-aldehyde, carboxymethyl cellulose aldehyde) are conjugated to the surface of protease, α-amylase, and lipase using two different strategies (reductive amination and alkylation with NHS-activated acid). Although the chemical modification of the enzymes is accompanied by losses in enzyme activity (maximum loss 40%), the covalent attachment of polymers increases the thermal stability and the stability in a standard detergent formulation compared to the unmodified enzymes. The enzyme-polymer conjugates are characterized by asymmetrical-flow field-flow fractionation and differential scanning microcalorimetry. Furthermore, it is demonstrated that conjugated enzymes still show performance in a real washing process. Enzyme-polymer conjugates show a potential as a stabilizing system for enzymes in detergents.

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