Abel B

References (3)

Title : Low Carbon Footprint Recycling of Post-Consumer PET Plastic with a Metagenomic Polyester Hydrolase - Sonnendecker_2022_ChemSusChem_15_e202101062
Author(s) : Sonnendecker C , Oeser J , Richter PK , Hille P , Zhao Z , Fischer C , Lippold H , Blazquez-Sanchez P , Engelberger F , Ramirez-Sarmiento CA , Oeser T , Lihanova Y , Frank R , Jahnke HG , Billig S , Abel B , Strater N , Matysik J , Zimmermann W
Ref : ChemSusChem , 15 :e202101062 , 2022
Abstract : Our planet is flooded with plastics and the need for sustainable recycling strategies of polymers has become increasingly urgent. Enzyme-based hydrolysis of post-consumer plastic is an emerging strategy for closed-loop recycling of polyethylene terephthalate (PET). The polyester hydrolase PHL7 isolated from a compost metagenome completely hydrolyzed amorphous PET films, releasing 91 mg of terephthalic acid per hour and mg of enzyme. Degradation rates of the PET film of 6.8 microm h -1 were monitored by vertical scanning interferometry. Structural analysis indicated the importance of leucine at position 210 for the extraordinarily high PET-hydrolyzing activity of PHL7. Within 24 h, 0.6 mg enzyme g PET -1 completely degraded post-consumer thermoform PET packaging in an aqueous buffer at 70 degreesC without any energy-intensive pretreatments. Terephthalic acid recovered from the enzymatic hydrolysate was used to synthesize virgin PET, demonstrating the potential of polyester hydrolases as catalysts in sustainable PET recycling processes with a low carbon footprint.
ESTHER : Sonnendecker_2022_ChemSusChem_15_e202101062
PubMedSearch : Sonnendecker_2022_ChemSusChem_15_e202101062
PubMedID: 34129279
Gene_locus related to this paper: 9firm-PHL7

Title : A novel microfluidic microelectrode chip for a significantly enhanced monitoring of NPY-receptor activation in live mode - Zitzmann_2017_Lab.Chip_17_4294
Author(s) : Zitzmann FD , Jahnke HG , Nitschke F , Beck-Sickinger AG , Abel B , Belder D , Robitzki AA
Ref : Lab Chip , 17 :4294 , 2017
Abstract : Lab-on-a-chip devices that combine, e.g. chemical synthesis with integrated on-chip analytics and multi-compartment organ-on-a-chip approaches, are a fast and attractive evolving research area. While integration of appropriate cell models in microfluidic setups for monitoring the biological activity of synthesis products or test compounds is already in focus, the integration of label-free bioelectronic analysis techniques is still poorly realized. In this context, we investigated the capabilities of impedance spectroscopy as a non-destructive real-time monitoring technique for adherent cell models in a microfluidic setup. While an initial adaptation of a microelectrode array (MEA) layout from a static setup revealed clear restrictions in the application of impedance spectroscopy in a microfluidic chip, we could demonstrate the advantage of a FEM simulation based rational MEA layout optimization for an optimum electrical field distribution within microfluidic structures. Furthermore, FEM simulation based analysis of shear stress and time-dependent test compound distribution led to identification of an optimal flow rate. Based on the simulation derived optimized microfluidic MEA, comparable impedance spectra characteristics were achieved for HEK293A cells cultured under microfluidic and static conditions. Furthermore, HEK293A cells expressing Y1 receptors were used to successfully demonstrate the capabilities of impedimetric monitoring of cellular alterations in the microfluidic setup. More strikingly, the maximum impedimetric signal for the receptor activation was significantly increased by a factor of 2.8. Detailed investigations of cell morphology and motility led to the conclusion that cultivation under microfluidic conditions could lead to an extended and stabilized cell-electrode interface.
ESTHER : Zitzmann_2017_Lab.Chip_17_4294
PubMedSearch : Zitzmann_2017_Lab.Chip_17_4294
PubMedID: 29119176

Title : Microfluidic Free-Flow Electrophoresis Based Solvent Exchanger for Continuously Operating Lab-on-Chip Applications - Zitzmann_2017_Anal.Chem_89_13550
Author(s) : Zitzmann FD , Jahnke HG , Pfeiffer SA , Frank R , Nitschke F , Mauritz L , Abel B , Belder D , Robitzki AA
Ref : Analytical Chemistry , 89 :13550 , 2017
Abstract : For miniaturization and integration of chemical synthesis and analytics on small length scales, the development of complex lab-on-chip (LOC) systems is in the focus of many current research projects. While application specific synthesis and analytic modules and LOC devices are widely described, the combination and integration of different modules is intensively investigated. Problems for in-line processes such as solvent incompatibilities, e.g., for a multistep synthesis or the combination of an organic drug synthesis with a cell-based biological activity testing system, require a solvent exchange between serialized modules. Here, we present a continuously operating microfluidic solvent exchanger based on the principle of free-flow electrophoresis for miscible organic/aqueous fluids. We highlight a proof-of-principle and describe the working principle for the model compound fluorescein, where the organic solvent DMSO is exchanged against an aqueous buffer. The DMSO removal performance could be significantly increased to 95% by optimization of the microfluidic layout. Moreover, the optimization of the inlet flow ratio resulted in a minimized dilution factor of 5, and we were able to demonstrate that a reduction of the supporting instrumentation is possible without a significant decrease of the DMSO removal performance. Finally, the compatibility of the developed solvent exchanger for cell based downstream applications was proven. The impedimetric monitoring of HEK293A cells in a continuously operating microfluidic setup revealed no adverse effects of the residual DMSO after the solvent replacement. Our solvent exchanger device demonstrates the power of micro-free-flow electrophoresis not only as a powerful technique for separation and purification of compound mixtures but also for solvent replacement.
ESTHER : Zitzmann_2017_Anal.Chem_89_13550
PubMedSearch : Zitzmann_2017_Anal.Chem_89_13550
PubMedID: 29164853