Enzymatic Production of Ecodiesel by Using a Commercial Lipase CALB, Immobilized by Physical Adsorption on Mesoporous Organosilica Materials

The synthesis of two biocatalysts based on a commercial Candida antarctica lipase B, CALB enzyme (E), physically immobilized on two silica supports, was carried out. The first support was a periodic mesoporous organosilica (PMO) and the second one was a commercial silica modified with octyl groups (octyl-MS3030). The maximum enzyme load was 122 mg enzyme/g support on PMO and 288 mg enzyme/g support on octyl-MS3030. In addition, the biocatalytic efficiency was corroborated by two reaction tests based on the hydrolysis of p-nitrophenylacetate (p-NPA) and tributyrin (TB). The transesterification of sunflower oil with ethanol was carried out over the biocatalysts synthesized at the following reaction conditions: 6 mL sunflower oil, 1.75 mL EtOH, 30 °C, 25 μL NaOH 10 N and 300 rpm, attaining conversion values over 80% after 3 h of reaction time. According to the results obtained, we can confirm that these biocatalytic systems are viable candidates to develop, optimize and improve a new methodology to achieve the integration of glycerol in different monoacylglycerol molecules together with fatty acid ethyl esters (FAEE) molecules to obtain Ecodiesel.

Great Location: About Effects of Surface Bound Neighboring Groups for Passive and Active Fine-Tuning of CO2 Adsorption Properties in Carbon Capture Materials

Better carbon capture materials are crucial for managing today’s and the future CO₂ level in the atmosphere. The past focus was on increasing adsorption capacities. One knows by now that controlling the heat of adsorption (DH_ads) is equally important. Is it too low, CO₂ uptake takes place at unfavorable conditions far from ambient and with insufficient selectivity. Is it too high, chemisorption occurs, and the materials can hardly be regenerated. The conventional approach for influencing DH_ads is the modification of the adsorbing center. This paper proposes an alternative strategy. The hypothesis is that fine-tuning of the molecular environment in direct vicinity to the adsorbing center (primary amines) is a powerful tool for the adjustment of CO₂-binding properties. Via click chemistry, any desired neighboring group (NG) can be incorporated on the surfaces of the resulting bifunctional, nanoporous organosilica materials. Passive NGs induce a change of the polarity of the surface, whereas active NGs are capable of a direct interaction with the active-center/ CO₂pair. The effects on DH_ads and also on the selectivity are studied in detail. A situation can be realized on the surface which resembles frustrated Lewis acid-base pairs, and the investigation of the binding-species by ¹³C solid-state NMR indicate that the push-pull effects could play an essential role not only for CO₂adsorption but also for its activation.

Great Location: About Effects of Surface Bound Neighboring Groups for Passive and Active Fine-Tuning of CO2 Adsorption Properties in Carbon Capture Materials

Better carbon capture materials are crucial for managing today’s and the future CO₂ level in the atmosphere. The past focus was on increasing adsorption capacities. One knows by now that controlling the heat of adsorption (DH_ads) is equally important. Is it too low, CO₂ uptake takes place at unfavorable conditions far from ambient and with insufficient selectivity. Is it too high, chemisorption occurs, and the materials can hardly be regenerated. The conventional approach for influencing DH_ads is the modification of the adsorbing center. This paper proposes an alternative strategy. The hypothesis is that fine-tuning of the molecular environment in direct vicinity to the adsorbing center (primary amines) is a powerful tool for the adjustment of CO₂-binding properties. Via click chemistry, any desired neighboring group (NG) can be incorporated on the surfaces of the resulting bifunctional, nanoporous organosilica materials. Passive NGs induce a change of the polarity of the surface, whereas active NGs are capable of a direct interaction with the active-center/ CO₂pair. The effects on DH_ads and also on the selectivity are studied in detail. A situation can be realized on the surface which resembles frustrated Lewis acid-base pairs, and the investigation of the binding-species by ¹³C solid-state NMR indicate that the push-pull effects could play an essential role not only for CO₂adsorption but also for its activation.

The Influence of Structural Gradients in Large Pore Organosilica Materials on the Capabilities for Hosting Cellular Communities

<div><div><div><div><p>Cells exist in the so-called extracellular matrix (ECM) in their native state, and numerous future applications require reliable and potent ECM-mimics. A perspective, which goes beyond ECM emulation, is the design of a host-material with features, which are not accessible in the biological portfolio. Such a feature would, for instance be, the creation of a structural or chemical gradient, and to explore how this special property influences the biological processes. First, we wanted to test if macroporous organosilica materials with appropriate surface modification can act as a host for the implementation of human cells like HeLa or LUHMES. It was possible to use a commercially available polymeric foam as a scaffold and coat it with a layer of a thiophenol-containing organosilica layer, followed by biofunctionalization with biotin using click chemistry and the subsequent coupling of streptavidin - fibronectin to it. More importantly, deformation of the scaffold allowed the generation of a permanent structural gradient. In this work, we show that the structural gradient has a tremendous influence on the capability of the described material for the accommodation of living cells. The introduction of a bi-directional gradient enabled the establishment of a cellular community comprising different cell types in spatially distinct regions of the material. An interesting perspective is to study communication between cell types or to create cellular communities, which can never exist in a natural enviornment.</p></div></div></div></div>

The Influence of Structural Gradients in Large Pore Organosilica Materials on the Capabilities for Hosting Cellular Communities

<div><div><div><div><p>Cells exist in the so-called extracellular matrix (ECM) in their native state, and numerous future applications require reliable and potent ECM-mimics. A perspective, which goes beyond ECM emulation, is the design of a host-material with features, which are not accessible in the biological portfolio. Such a feature would, for instance be, the creation of a structural or chemical gradient, and to explore how this special property influences the biological processes. First, we wanted to test if macroporous organosilica materials with appropriate surface modification can act as a host for the implementation of human cells like HeLa or LUHMES. It was possible to use a commercially available polymeric foam as a scaffold and coat it with a layer of a thiophenol-containing organosilica layer, followed by biofunctionalization with biotin using click chemistry and the subsequent coupling of streptavidin - fibronectin to it. More importantly, deformation of the scaffold allowed the generation of a permanent structural gradient. In this work, we show that the structural gradient has a tremendous influence on the capability of the described material for the accommodation of living cells. The introduction of a bi-directional gradient enabled the establishment of a cellular community comprising different cell types in spatially distinct regions of the material. An interesting perspective is to study communication between cell types or to create cellular communities, which can never exist in a natural enviornment.</p></div></div></div></div>

Direct nanoimprinting of nanoporous organosilica films consisting of covalently crosslinked photofunctional frameworks

Nanoimprinting of organosilica materials is a new powerful tool for preparing nanostructured robust films that are suitable for photofunctional applications.

The influence of structural gradients in large pore organosilica materials on the capabilities for hosting cellular communities

Chemical and structural gradients in biofunctionalized organosilica–polymer nanocomposites control cell adhesion properties and open perspectives for artificial cellular community systems.