In-situ sol-gel modification strategies to develop a monolith continuous microreactor for enzymatic green reactions

Pirozzi, Domenico; Abagnale, Maria; Minieri, Luciana; Pernice, P.; Aronne, Antonio

doi:10.1016/j.cej.2016.08.035

Cited by 17 publications

(8 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…50 The enzyme immobilization results in new peaks, particularly the Amide I band (1,600 cm −1 to 1,700 cm −1 ) related to C-O stretching vibrations and the Amide II band (1,510 cm −1 to 1,580 cm −1 ) related to N-H bending. [51][52] New peaks between 3,000 cm −1 and 3,700 cm −1 are indicative of N-H stretching and side chain stretching. [53][54] In addition, zeta potential measurements reveal surface charge inversion, confirming the successful deposition of layers (Figure 2(B)).…”

Section: Characterization Of the Immobilized Enzymementioning

confidence: 99%

Improving β-Galactosidase-Catalyzed Transglycosylation Yields by Cross-Linked Layer-by-Layer Enzyme Immobilization

Alavijeh

Meyer

Gras

et al. 2020

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

The biotransformation of lactose into gut-bioactive glycans catalyzed by βgalactosidase can give economic value to lactose-rich side streams generated in the food or dairy industry. Herein, we study the immobilization of the commercially used β-galactosidase from Bacillus circulans onto silica particles using an enzyme immobilization technology involving a cross-linked layer-by-layer encapsulation method. The immobilized β-galactosidase was used for the synthesis of Nacetyllactosamine (LacNAc) as an important precursor for numerous bioactive compounds and a prebiotic in itself. Techniques including molecular analysis, enzyme activity determination, secondary structure analysis, thermodynamic characterization as well as the determination of thermal and operational stability were conducted to characterize the immobilized enzyme. Changes in the activity of the enzyme after immobilization were attributed to possible changes in electrostatic, covalent and protein-protein interactions. Immobilization significantly improved enzymatic LacNAc yield compared to the free enzyme. In turn, this improved the economics and the sustainability of the process. The immobilized enzyme encapsulated in multilayer films was significantly more stable in the presence of divalent cations and its thermostability also substantially increased, with the thermal denaturation activation energy increasing from 53 kJ mol -1 to 294 kJ mol -1 . The immobilized enzyme was successfully reused in eight consecutive reaction cycles with no significant reduction in the LacNAc yield. The improved transgalactosylation yield and productivity, higher stability and reusability obtained with this immobilization method provide new opportunities for industrial applications.

show abstract

Section: Characterization Of the Immobilized Enzymementioning

confidence: 99%

Improving β-Galactosidase-Catalyzed Transglycosylation Yields by Cross-Linked Layer-by-Layer Enzyme Immobilization

Alavijeh

Meyer

Gras

et al. 2020

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

show abstract

“…The shape and the high void fraction of these macrocellular foams make them particularly suitable to be used in continuous flow reactors . Also, the specific surface area – which is generally high due to the presence of micro‐ and mesopores in the macropore walls – can be easily functionalized, allowing the monolith to be used as support for catalyst particles and enzymes …”

Section: Figurementioning

confidence: 99%

Macrocellular Titanosilicate Monoliths as Highly Efficient Structured Olefin Epoxidation Catalysts

et al. 2019

View full text Add to dashboard Cite

Self-standing macrocellular titanosilicate monolith foams are obtained using a one-pot sol-gel route and show excellent performance in the epoxidation of cyclohexene. Thanks to the High Internal Phase Emulsion (HIPE) templating method, the materials feature a high void fraction, a hierarchically porous texture and good mechanical strength. Highly dispersed Ti species can be incorporated in tetrahedral coordination in the silica matrix. These characteristics allow the obtained 'SiTi(HIPE)' materials to reach high catalytic turnover in the epoxidation of cyclohexene. The monoliths can advantageously be used to run the reaction in continuous flow mode.Titanosilicates are an important class of materials that catalyze selective oxidation reactions. [1] For example, the combination of TS-1 zeolite -in which Ti atoms substitute Si atoms in the crystalline framework -with H 2 O 2 is omnipresent in industrial applications, notably for hydroxylation and epoxidation reactions. [2,3] The crystallinity and the intrinsic hydrophobicity of TS-1 make this material particularly efficient to catalyze the oxidation of small substrates with high selectivities. [4] However, the microporosity of TS-1 makes it less efficient for the conversion of bulky olefins, as the restricted diffusion of the reactants and products in and out the porosity can severely lower the catalytic activity which is consequently mainly restrained to the external surface. [5,6] An additional limitation is linked to the fact that the Ti loading incorporated into the zeolitic framework can hardly be tuned -with a typical maximal Ti loading of 2.5 % (here and after the loading is expressed as mol Ti/(mol Ti + mol Si) × 100 %). [7] These issues triggered intensive research on the incorporation of titanium in silicabased materials with larger pores in order to broaden the range of applications for titanosilicates. [8][9][10] New strategies in this field are flourishing, taking benefits of bottom-up sol-gel routes [11] involving templating methods -possibly combined to supercritical [12,13] or aerosol [14,15] drying strategies -or realized under non-aqueous conditions. [16][17][18] Despite those successes, the resulting materials are often obtained in the form of fine powders which require further steps to shape the catalysts as extrudates, pellets or monoliths, before they could be used in industrial flow processes. [19] This shaping step represents an additional challenge as it necessitates a fine control of the mechanical properties and the diffusion regimes without sacrificing the intrinsic performance of the catalyst. Alternatively, the catalyst can be dispersed onto a pre-shaped solid support [20][21][22] that should meet several specifications (texture, surface composition, mechanical stability, etc.). With such strategy, a challenge is to maximize the loading and the dispersion of the catalyst while avoiding leaching and/or deactivation. [23] Thus, the one-step preparation of Ti-containing materials that do not require further shaping steps is highly sought f...

show abstract

“…Moreover, the column format of monolith enables continuous use of the enzyme while no contamination of the products with the biocatalysts occurs. The advantages of monolithic supports for enzyme immobilizations have been demonstrated by several successful examples where immobilized enzymes were used to catalyze substrates dissolved both in aqueous media and organic solvents . The drawback of porous polymer monoliths relies on their small surface areas due to the absence of small pores, which might result in low immobilization capacities for enzymes.…”

Section: Introductionmentioning

confidence: 99%

Reversible Two‐Enzyme Coimmobilization on pH‐Responsive Imprinted Monolith for Glucose Detection

Luo

Švec

et al. 2019

Biotechnology Journal

View full text Add to dashboard Cite

A new enzymatic glucose biosensor based on reversible co-immobilization of horseradish peroxidase (HRP) and glucose oxidase (GOx) on a pH-responsive imprinted monolith is prepared. The poly(4-vinylphenylboronic acid)-grafted imprinted polymer using HRP as a template is formed via surface initiated atom transfer radical polymerization within the pores of brominated poly(glycidyl methacrylate-co-ethylene dimethacrylate) macroporous monolith contained in a 100 μm I.D. capillary column. The two enzymes conjugate is formed via the strong affinity interaction between biotin-labeled GOx and streptavidin-labeled HRP. The modulation of the external pH value enables reusability of the biosensor simply using stripping of the inactive enzymes at a low pH value and subsequent immobilization of fresh enzymes at a high pH value. Under the optimized conditions, the enzymatic biosensor features excellent performance in detection of glucose with a linear range of its concentration from 0.11 to 38.85 mmol/L and a limit of detection of 0.03 mmol/L. A relative standard deviation of 3.7% is calculated from determination of twenty glucose samples. This novel enzymatic sensing system is successfully applied for determination of glucose in human serum, and confirms an enhancement both in selectivity and specificity compared to the more traditionally clinical methods.

show abstract

In-situ sol-gel modification strategies to develop a monolith continuous microreactor for enzymatic green reactions

Cited by 17 publications

References 43 publications

Improving β-Galactosidase-Catalyzed Transglycosylation Yields by Cross-Linked Layer-by-Layer Enzyme Immobilization

Improving β-Galactosidase-Catalyzed Transglycosylation Yields by Cross-Linked Layer-by-Layer Enzyme Immobilization

Macrocellular Titanosilicate Monoliths as Highly Efficient Structured Olefin Epoxidation Catalysts

Reversible Two‐Enzyme Coimmobilization on pH‐Responsive Imprinted Monolith for Glucose Detection

Contact Info

Product

Resources

About