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Biocatalysis has emerged in recent decades toward a widely applied catalysis technology in the chemical industry. In particular the fine chemicals and pharmaceuticals industries benefit from the advantages of biocatalysis, which made its way to a dominating industrial core technology for manufacturing chiral molecules. However, often biocatalysis is still to a certain extent away from having solved all challenges being needed for a "perfect industrial process technology". Among existing challenges are, e.g., stability under process conditions and easy separation of the catalyst from the reaction mixture with the additional option of recyclability. Here metal‐organic framework (MOF) structures offer unique advantages, which can be beneficial for biocatalysis. A particular valuable option is integration of enzymes into MOF‐subunits, thus having a potential positive impact on stability (by reducing the tendency of unfolding) and enabling compartmentalization as a beneficial strategy in, e.g., chemoenzymatic synthesis. In this "Perspective"‐article, first the state of the art in biocatalysis is briefly summarized together with current challenges. Then, a short overview about current research achievements in "merging" MOF chemistry and biocatalysis is given as well as an outlook written from a biocatalysis practitioner's view, how MOF‐enzyme hybrid systems can play a major role in future process development to overcome existing hurdles of enzymatic catalysis. [ABSTRACT FROM AUTHOR]

In recent years, biopolymers have been widely used in various fields of medicine. Before using any polymer, its biocompatibility should be examined. Polyacrylic acid (PAA), a polyelectrolyte, is known to be used as an adjuvant effect in immunology, anti-thrombogenic effect in medical experiments, and as a carrier in drug delivery systems. Although there are studies on various conjugates and nanoparticles of PAA, studies on its toxicity alone are limited. Determination of toxicity in biopolymer studies is extremely important. Cultures of various cells are used for toxicity analyses. This study aimed to investigate the toxicity of PAA in human breast cancer (MCF-7) and mouse fibroblast (L-929) cell lines by various methods. Cell culture, 3-(4,5-dimethyltriazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), trypan blue and 4,6-diamidino 2 phenylindole (DAPI) methods were used in the study. The half-maximal effective concentration (EC50) value of PAA was 6.6 mg/ml in MCF 7 cells and 1.8 mg/ ml in L-929 cells. Apoptosis was observed in cells on the increasing PAA concentration with DAPI. With these results, the cytotoxic properties of PAA were determined in vitro. Accordingly, the biocompatibility of polymers to be used in modeling should be supported by in vitro and in vivo studies.

Among current challenges for the chemical industry is the shift of the raw material basis from fossil feedstocks to renewable sources, which is also of relevance for the field of the industrial product class of alkenes with a chain length of C6 or more. A process concept based on CO2 and renewable energy is the conversion of 1-hexanol, being accessable from such renewable sources, to hexene sources. In this contribution, the dehydration of 1-hexanol catalyzed by Lewis acids such as metal triflates is presented. The prioritized catalysts have been also applied for the dehydration of C7–C12 primary alcohols. Hf(IV) and Ti(IV) triflates have shown the highest conversions in comparison to 13 other metal triflates, leading to high alkene yields of more than 70%. Furthermore, this study revealed a process running at energy-saving conditions and the so far lowest reaction temperatures for a chemocatalytic dehydration of primary alcohols being in the range of 140–180 °C only. [ABSTRACT FROM AUTHOR]

The aim of the present study is to develop a new drug delivery system with the aid of nanomedicine for aflibercept molecule and to evaluate optimization, characterization, in vitro drug release profile and toxicity on human retinal pigment epithelial (ARPE-19) and human retinal endothelial cell (HREC) lines. Poly lactic-co-glycolic acid (PLGA) aflibercept nanoparticles were prepared using the doubleemulsion diffusion and solvent evaporation technique. The Dynamic Light Scattering (DLS), UV-vis absorption (UV), Scanning Electron Microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy techniques were carried out to characterize the nanoparticles. Cytotoxic effects of blank PLGA and Aflibercept-loaded PLGA nanoparticles on ARPE-19 and HREC cells were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide salt (MTT) assay. Aflibercept-loaded PLGA nanoparticles with a round shape and smooth surface were produced and verified with SEM images. The average particle size, polydispersity index (Pdl) and zeta potential value were 262±6.6 mV; 0.12±0.016 mV and +6.27±4 mV respectively. The release of aflibercept was extended up to 48 hours with the 85.2Ü.08 % encapsulation and 10.4±4.5 % loading efficiency. The formation of encapsulation was verified with FT-IR analysis and in vitro toxic effects on both cell lines have also been observed at various doses ranging from 0.1 pM to 0.5 pM. The development of nanoparticle-based drug delivery systems is challenging and time consuming, and requires optimization of several factors before their use in clinical practice. 48 hours in vitro relase may not adequate to claim improvement over Aflibercept delivery in vivo. Further studies are needed. [ABSTRACT FROM AUTHOR]