Enzymatic Polymerization Research Articles

Target-Triggered Ultrafast Chondroitin Gelation Enabled Power-Free and Point-of-Care Bioassays.

Point-of-care (POC) tests increasingly highlight the importance of portable, cost-effective, and visually quantitative detection of biomarkers. Herein, we developed a power-free and visual signal-readout POC sensor based on the target-triggered ultrafast gelation process. In the gelation process, the target triggered the cascade reaction catalyzed by oxidase and ferrous glycinate to produce carbon radicals that immediately initiated the rapid polymerization and cross-linking of acryloylated chondroitin sulfate and dimethylacrylamide. This highly efficient enzymatic polymerization process contributed to the ultrafast generation of chondroitin hydrogel within 1 min at 25 °C. The increase in viscosity of aqueous solution resulted from hydrogel formation was then visually measured according to the distance of solution migration on a tick-labeled pH test strip, which thus realized the quantification of a target. By utilizing glucose oxidase as an oxidase model during the gelation process, this POC sensor was successfully employed in the rapid quantitative detection of glucose without the need for any auxiliary instruments. Benefiting from the specificity and stability of the enzymatic polymerization reaction, the sensor exhibited excellent performance in the detection of glucose in clinical blood samples. Moreover, the sensor was further extended to uric acid detection and enabled accurate assay in clinical urine samples, which indicated the versatility and practicability of this sensor in the POC test.

Electron Paramagnetic Resonance Analysis of Hydroquinone Polymerization Catalyzed by Small Laccase

AbstractLaccases are multi‐copper oxidases (MCOs) that oxidize a broad range of substrates while reducing molecular oxygen to water. Although much effort has been made to elucidate the catalytic mechanism of laccases, information about reactive catalytic intermediates during catalysis is not yet fully understood. Herein, hydroquinone (HQ) polymerization catalyzed by prokaryotic small laccase (SLAC) was investigated by electron paramagnetic resonance (EPR) spectroscopy to provide more information on the catalytic mechanism. Briefly, free radical intermediates during the catalysis were investigated by real‐time in situ EPR measurement to monitor the formation and transformation of free radicals. A paramagnetic species was identified which was attributed to a copolymer formed by hydroquinone, benzoquinone, and semiquinone radical. In addition, the low‐temperature EPR spectrum of the trinuclear copper center during catalysis not only revealed tentative rotational motion of the histidine imidazole rings coordinating the TNC upon electron uptake but also provided evidence of the formation of oxygen bridge at TNC during the reaction, represented by the observation of a new type 2 copper component featured larger g// values and smaller A// values. Together, EPR spectroscopic insights into the catalytic intermediates during enzymatic hydroquinone polymerization have extended the knowledge of the biophysical characteristics and catalytic mechanism of SLAC.

Urushiol oligomer preparation and evaluations of their antibacterial, antioxidant, and thermal stability

There have been studies published on the composition and coating uses of raw lacquers following enzymatic oxidative polymerization. The change of urushiol’ thermal stability and biological activity following polymerization to create oligomer, however, has received little attention. This work using silica gel column chromatography to separate urushiol and urushiol oligomer from polymerized raw lacquer and assessed its antibacterial, antioxidant, and thermal stability in an effort to decrease the allergenicity of urushiol and increase its application. By using gel chromatography, the urushiol oligomer were discovered to be polymers with 2–5 degrees of polymerization. According to characterization results from techniques like UV, FT-IR, and 1H NMR, urushiol was converted into urushiol oligomer by addition reactions, and C–C coupling. The findings demonstrated that the urushiol oligomer’ IC50 values for scavenging DPPH and ABTS free radicals were 40.8 and 27.4 μg/mL, respectively, and that their minimum inhibitory concentrations against Staphylococcus aureus and Staphylococcus epidermidis were 250 and 125 μg/mL. The urushiol oligomer’s thermogravimetric differential curve peak temperature (461.8 °C) was higher than urushiol’s (239.5 °C), indicating that urushiol undergoes polymerization with enhanced thermal stability. The study’s findings establish a foundation for the use of polymerized urushiol and urushiol oligomer in applications including functional materials and additives.

In Vitro Culture of Human Dermal Fibroblasts on Novel Electrospun Polylactic Acid Fiber Scaffolds Loaded with Encapsulated Polyepicatechin Physical Gels.

Polyepicatechin (PEC) in a hydrogel has previously shown promise in enhancing physiological properties and scaffold preparation. However, it remains unclear whether PEC-based fibers can be applied in skin tissue engineering (STE). This study aimed to synthesize and characterize electrospun PEC physical gels and polylactic acid (PLA) scaffolds (PLAloadedPECsub) for potential use as constructs with human dermal fibroblasts (HDFs). PEC was produced through enzymatic polymerization, as confirmed by Fourier transform infrared (FTIR) spectroscopy. Scanning electron microscopy (SEM) demonstrated the feasibility of producing PLAloadedPECsub by electrospinning. The metabolic activity and viability of HDFs cocultured with the scaffolds indicate that PLAloadedPECsub is promising for the use of STE.

In Situ Enzymatic Polymerization of Ethylene Brassylate Mediated by Artificial Plant Cell Walls in Reactive Extrusion.

Herein, we describe a solvent-free bioinspired approach for the polymerization of ethylene brassylate. Artificial plant cell walls (APCWs) with an integrated enzyme were fabricated by self-assembly, using microcrystalline cellulose as the main structural component. The resulting APCW catalysts were tested in bulk reactions and reactive extrusion, leading to high monomer conversion and a molar mass of around 4 kDa. In addition, we discovered that APCW catalyzes the formation of large ethylene brassylate macrocycles. The enzymatic stability and efficiency of the APCW were investigated by recycling the catalyst both in bulk and reactive extrusion. The obtained poly(ethylene brassylate) was applied as a biobased and biodegradable hydrophobic paper coating.

Engineering Conductive Hydrogels with Tissue‐like Properties: A 3D Bioprinting and Enzymatic Polymerization Approach

Hydrogels are promising materials for medical devices interfacing with neural tissues due to their similar mechanical properties. Traditional hydrogel‐based bio‐interfaces lack sufficient electrical conductivity, relying on low ionic conductivity, which limits signal transduction distance. Conducting polymer hydrogels offer enhanced ionic and electronic conductivities and biocompatibility but often face challenges in processability and require aggressive polymerization methods. Herein, we demonstrate in situ enzymatic polymerization of π‐conjugated monomers in a hyaluronan (HA)‐based hydrogel bioink to create cell‐compatible, electrically conductive hydrogel structures. These structures were fabricated using 3D bioprinting of HA‐based bioinks loaded with conjugated monomers, followed by enzymatic polymerization via horseradish peroxidase. This process increased the hydrogels’ stiffness from about 0.6 to 1.5 kPa and modified their electroactivity. The components and polymerization process were well‐tolerated by human primary dermal fibroblasts and PC12 cells. This work presents a novel method to fabricate cytocompatible and conductive hydrogels suitable for bioprinting. These hybrid materials combine tissue‐like mechanical properties with mixed ionic and electronic conductivity, providing new ways to use electricity to influence cell behavior in a native‐like microenvironment.

Synthesis of a new unnatural polysaccharide, 2-deoxy-β(1→3)-glucan, by β−1,3-glucan phosphorylase-catalyzed enzymatic polymerization

Abstract We successfully synthesized a new unnatural polysaccharide, 2-deoxy-β(1→3)-glucan, by β−1,3-glucan phosphorylase-catalyzed enzymatic polymerization of a D-glucal monomer from a cellobiose primer, owing to recognition of such non-native substrates by the enzyme. Because of solubility of the product in several high polar organic solvents, acetylation as an example of its derivatizations smoothly occurred using acetic anhydride in the presence of base/catalyst in a DMF solvent. The NMR analysis of the acetylated derivative strongly supported the β(1→3)-linked chain structure.

Enzymatic synthesis of biobased aliphatic-hetero-aromatic furanic copolyesters: Influence of furan dimethyl ester isomerism

Due to environmental concerns, there is a growing demand for more sustainable materials. As a result, the renewability of the raw materials and catalysts involved in production is important for rendering sustainable and circular polymers. Due to its environmentally friendly nature and high selectivity, enzymatic polymerization is a viable approach for producing such polymers. Recent developments in the field of biobased furan building blocks have led to renewed interest in 2,4-furandicarboxylic acid (2,4-FDCA) and 3,4-FDCA. Furthermore, far too little attention has been given to 2,5-bis(hydroxymethyl)furan (2,5-BHMF), another class of hetero-aromatic diol that can be derived from carbohydrates. These furan monomers are attractive due to their potential for producing novel biobased polyesters with interesting properties. To date, however, there has been little discussion about the use of these materials for polymerization via enzymatic approaches. Hence, a comparative study of CALB-catalyzed copolymerization involving two FDCA dimethyl ester isomers, either 2,4- or 3,4-DMFDCA, with 2,5-BHMF and various aliphatic diols has been carried out. This provides further insight into the regioselectivity promoted by CALB for asymmetrical 2,4-DMFDCA over symmetrical 3,4-DMFDCA. This is evidenced by the high degree of polymerization achieved with a weight-average molecular weight of up to 14 kg mol−1. In agreement with previous findings, a preference for the formation of cyclic species from symmetrical monomers catalyzed by CALB was observed. Structural characterization and thermal and crystallinity analyses were used to assess the correlation between structure and material properties.

Synthesis of linear polyesters bearing amino groups via lipase-catalyzed polymerization of N-protected monomer and deprotection

Linear biodegradable polyesters with a controlled number of side chains of amino groups have been synthesized. Such polyesters with a large number of amino side groups can be conjugated with a wide variety of functional molecules to obtain multi-functional biodegradable polyesters. In this study, poly(1,3-propylene-co-2-amino-1,3-propylene) adipate) (P(P-co-AP)A) was synthesized by enzymatic polymerization of divinyl adipate, 1,3-propanediol, and N-Boc-2-amino-1,3-propanediol (BocAPDO), and subsequent deprotection under strong acidic conditions. The mild reaction conditions and the specificity of the enzymatic polymerization could effectively inhibit side reactions, while the protecting groups of the monomers prevented polymer branching from the amino groups. It was found that the introduction rates of BocAPDO in the polymers could be well-controlled as the feeding rates changed from 0 to 100 mol%. After the deprotection and desalting, the ester groups in the main chain gradually converted into amide groups by intramolecular ester aminolysis at room temperature for a few days due to nucleophilic free amino groups. It was also found that the synthesized functional copolymers were all amorphous, since the random component of amino groups disrupted the crystallinity of poly(1,3-propylene adipate) (PPA). The glass transition temperature gradually increased with the increase in the content of 2-amino-1,3-propylene adipate (APA), eventually reaching −0.4 °C at the APA content of 100 mol% due to the intermolecular hydrogen bonding. Moreover, P(P-co-AP)A shows high hygroscopicity, where 3.9 wt% and 8.1 wt% of water were absorbed in the polymers with the APA contents of 50 and 100 mol%, respectively, when left in air at 60–70 % humidity for 6 h. Thus, the hydrophilicity dramatically improved with the increase in the APA content, eventually resulting in the acquisition of water solubility. The model post-polymerization modification using butyric acid was also conducted, and it was confirmed that carboxylic acids could be conjugated to the polymers by simple condensation reaction. Since polymerization of functional monomers is generally susceptible to the polarity of metal catalysts, the mild and selective reaction employed in this study could realize a higher content of various functional groups in the side chains of polyesters leading to a newly designed multi-functional polyester.

Bonding of Lignin and Coniferyl Alcohol by a Redox Shuttle of Low-Molecular-Weight Lignols in Enzymatic Oxidative Dehydrogenative Polymerization.

Lignin is an aromatic polymer that constitutes plant cell walls. The polymerization of lignin proceeds by radical coupling, and this process requires radicalization of the phenolic end of lignin by enzymes. However, due to the steric hindrance between enzymes, lignin, and polysaccharides, the direct oxidation of the phenolic end of lignin by the enzyme would be difficult, and the details of the growth of lignin are still unknown. In this study, enzymatic dehydrogenative polymerization experiments were conducted using coniferyl alcohol (CA) and the deuterium-labeled lignin model compound (D-LM) under a noncontact condition in which horseradish peroxidase cannot directly oxidize D-LM due to separation by a dialysis membrane. Analysis of deuterium-labeled degraded compounds obtained by a combination of methylation and thioacidolysis revealed the formation of the bond between the phenolic end of D-LM and CA, suggesting that membrane-permeable, low-molecular-weight lignols functioned as a redox shuttle mediator.

Degradable π-Conjugated Polymers.

The integration of next-generation electronics into society is rapidly reshaping our daily interactions and lifestyles, revolutionizing communication and engagement with the world. Future electronics promise stimuli-responsive features and enhanced biocompatibility, such as skin-like health monitors and sensors embedded in food packaging, transforming healthcare and reducing food waste. Imparting degradability may reduce the adverse environmental impact of next-generation electronics and lead to opportunities for environmental and health monitoring. While advancements have been made in producing degradable materials for encapsulants, substrates, and dielectrics, the availability of degradable conducting and semiconducting materials remains restricted. π-Conjugated polymers are promising candidates for the development of degradable conductors or semiconductors due to the ability to tune their stimuli-responsiveness, biocompatibility, and mechanical durability. This perspective highlights three design considerations: the selection of π-conjugated monomers, synthetic coupling strategies, and degradation of π-conjugated polymers, for generating π-conjugated materials for degradable electronics. We describe the current challenges with monomeric design and present options to circumvent these issues by highlighting biobased π-conjugated compounds with known degradation pathways and stable monomers that allow for chemically recyclable polymers. Next, we present coupling strategies that are compatible for the synthesis of degradable π-conjugated polymers, including direct arylation polymerization and enzymatic polymerization. Lastly, we discuss various modes of depolymerization and characterization techniques to enhance our comprehension of potential degradation byproducts formed during polymer cleavage. Our perspective considers these three design parameters in parallel rather than independently while having a targeted application in mind to accelerate the discovery of next-generation high-performance π-conjugated polymers for degradable organic electronics.

Effect of Salts on Laccase-Catalyzed Polymerization of Lignosulfonate.

Enzymatic polymerization of lignosulfonate (LS) has a high potential for various applications ranging from coatings to adhesives. Here, the effect of different ions in low concentrations on enzymatic polymerization of LS was investigated, including salt solutions consisting of mono- and dicarboxylic acids, sulfate, phosphate and chloride with sodium as counter ion. LS polymerization was followed by viscometry and size exclusion (SEC) chromatography. Interestingly, there was only a small effect of ions on the activity of the laccase on standard substrate ABTS, while the effect on polymerization of LS was substantially different. The presence of acetate led to a 39 % higher degree of polymerization (DP) for LS. Small angle X-ray scattering (SAXS) revealed that the structure of the enzyme was largely unaffected by the ions, while the determination of the zeta potential showed that those ions conveying higher negative surface charges onto LS particles showed lower DPs, than those not affecting the surface charge. Further, electron paramagnetic resonance (EPR) spectroscopy showed 5-times higher intensity in phenoxyl radicals for the monovalent ions compared to the divalent ones. It was concluded that the DPs of LS could be tuned in the presence of certain ions, by facilitating the interaction between the laccase substrate-binding site and the LS molecules.

Enzymatic Assembly of Chitosan-Based Network Polysaccharides and Their Encapsulation and Release of Fluorescent Dye.

We prepared network polysaccharide nanoscopic hydrogels by crosslinking water-soluble chitosan (WSCS) with a carboxylate-terminated maltooligosaccharide crosslinker via condensation. In this study, the enzymatic elongation of amylose chains on chitosan-based network polysaccharides by glucan phosphorylase (GP) catalysis was performed to obtain assembly materials. Maltoheptaose (Glc7) primers for GP-catalyzed enzymatic polymerization were first introduced into WSCS by reductive amination. Crosslinking of the product with the above-mentioned crosslinker by condensation was then performed to produce Glc7-modified network polysaccharides. The GP-catalyzed enzymatic polymerization of the α-d-glucose 1-phosphate monomer from the Glc7 primers on the network polysaccharides was conducted, where the elongated amylose chains formed double helices. Enzymatic disintegration of the resulting network polysaccharide assembly successfully occurred by α-amylase-catalyzed hydrolysis of the double helical amyloses. The encapsulation and release of a fluorescent dye, Rhodamine B, using the CS-based network polysaccharides were also achieved by means of the above two enzymatic approaches.

Enzymatic polymerization of the flavonoids dihydroquercetin (taxifolin) and (+)-catechin in betaine-based deep eutectic solvent and products characterization

Enzymatic polymerization of the flavonoids dihydroquercetin (taxifolin) and (+)-catechin in betaine-based deep eutectic solvent and products characterization

Enzymatic Synthesis of Copolyesters with the Heteroaromatic Diol 3,4-Bis(hydroxymethyl)furan and Isomeric Dimethyl Furandicarboxylate Substitutions.

Polyesters from furandicarboxylic acid derivatives, i.e., dimethyl 2,5-furandicarboxylate (2,5-DMFDCA) and 2,4-DMFDCA, show interesting properties among bio-based polymers. Another potential heteroaromatic monomer, 3,4-bis(hydroxymethyl)furan (3,4-BHMF), is often overlooked but holds promise for biopolymer synthesis. Cleaning and greening synthetic procedures, i.e., enzymatic polymerization, offer sustainable pathways. This study explores the Candida antarctica lipase B (CALB)-catalyzed copolymerization of 3,4-BHMF with furan dicarboxylate isomers and aliphatic diols. The furanic copolyesters (co-FPEs) with higher polymerization degrees are obtained using 2,4-isomer, indicating CALB's preference. Material analysis revealed semicrystalline properties in all synthesized 2,5-FDCA-based co-FPEs, with multiple melting temperatures (Tm) from 53 to 124 °C and a glass-transition temperature (Tg) of 9-10 °C. 2,4-FDCA-based co-FPEs showed multiple Tm from 43 to 61 °C and Tg of -14 to 12 °C; one of them was amorphous. In addition, all co-FPEs showed a two-step decomposition profile, indicating aliphatic and semiaromatic segments in the polymer chains.

Application of ultrasound-assisted compression and 3D-printing semi-solid extrusion techniques to the development of sustained-release drug delivery systems based on a novel biodegradable aliphatic copolyester

The purpose of this study was to investigate the ability of two advanced hot-processing technologies, Ultrasound-Assisted Compression (USAC) and 3D-printing Semi-solid Extrusion (SSE), to manufacture sustained-release drug delivery systems based on a novel biodegradable aliphatic copolyester. The copolymer was synthesized from ω-pentadecalactone (PDL), 1,4-cyclohexanedimethanol (CHDM) and dimethyl succinate (DMS) (monomer ratio PDL/CHDM/DMS 70/30/30) by enzymatic ring opening polymerization and two-step melt polycondensation processes and has a random microstructure, a high molecular weight (107,100 g mol−1) and a relatively low melting point (∼65 °C). The antibacterial agent metronidazole (MTZ) was chosen as model drug and binary physical mixtures copolymer:drug were prepared at 90:10 and 70:30 w/w ratios. Thermal analysis studies evidenced that the formulations could be processed below their degradation temperatures. Drug delivery devices with dense and meshed structures were manufactured using USAC and SSE techniques, respectively, with USAC devices exhibiting more reproducible physical properties than the SSE systems. Powder X-ray diffraction and scanning electron microscopy studies showed a partial sintering of the copolyester during USAC processing while MTZ remained mostly crystalline. In contrast, the copolymer melted and the drug underwent some amorphization when processed using SSE. In vitro drug release studies in phosphate buffer (pH 6.8) showed that, after an initial burst release of metronidazole, USAC and SSE devices exhibited a prolonged and/or sustained drug release over 20 days. The initial burst release was dependent on the manufacturing technique and the drug/polymer ratio, being minimized for SSE devices containing 10 wt% MTZ. The whole drug release profiles fitted well to the Peppas-Sahlin model, being drug diffusion the predominant release mechanism. After the burst release, the sustained release period of USAC and SSE devices containing 10 wt% MTZ showed a good fit to the zero-order kinetic model, with faster drug release from the SSE devices due to the larger surface area of their meshed structure. In conclusion, this work demonstrates that processing the aliphatic copolyester by both USAC and SSE technologies provides an attractive strategy to manufacture biodegradable drug delivery systems for long-term release of metronidazole.

Relationship between the poly(glycerol adipate) prepolymers chain microstructure and linear viscoelastic properties of the elastomers

This paper investigates the influence of the time of enzymatic polymerization of glycerol and divinyl adipate on the chain microstructure and the thermal and linear viscoelastic properties (LVE) of the poly(glycerol adipate) prepolymer (pPGA). The immobilized Candida antarctica lipase B (CALB) was used as a regioselective catalyst in the polytransesterification reaction. A series of pPGA prepolymers were synthesized at different duration times of 8, 24, 48 and 72 h and the degree of polymerization (DP) and degree of branching (DB) were determined based on a quantitative NMR analysis. Due to lack in the literature of the described relationship between the properties of the pPGA prepolymers and the PGA elastomers, the main goal of the research was to correlate the microstructure of the prepolymers with linear viscoelastic properties of the elastomers obtained by thermal crosslinking of the respective prepolymers. The respective pPGA prepolymers were cured at 110 °C for 5 days to obtain PGA elastomers. The LVE properties of the PGA elastomers were investigated based on the master curves of the storage (G') and loss (G") modulus. The differences in DP and BD for the pPGA prepolymers translated into the PGA elastomer crosslinking densities and the rubbery plateau modulus (G0). It was shown for the first time that the minor differences in the structure of the pPGA prepolymers (DP of 13 and 21, and DB of 8.4% and 9.7% for the pPGA prepolymers synthesized for 8 and 24 h, respectively) translate into significant differences in the LVE of the PGA elastomers (G0 of 116 kPa and 50 kPa for the PGA elastomers derived from pPGA8 and pPGA24 prepolymers, respectively).

Mechanically Controlled Enzymatic Polymerization and Remodeling.

In nature, proteins possess the remarkable ability to sense and respond to mechanical forces, thereby triggering various biological events, such as bone remodeling and muscle regeneration. However, in synthetic systems, harnessing the mechanical force to induce material growth still remains a challenge. In this study, we aimed to utilize low-frequency ultrasound (US) to activate horseradish peroxidase (HRP) and catalyze free radical polymerization. Our findings demonstrate the efficacy of this mechano-enzymatic chemistry in rapidly remodeling the properties of materials through cross-linking polymerization and surface coating. The resulting samples exhibited a significant enhancement in tensile strength, elongation, and Young's modulus. Moreover, the hydrophobicity of the surface could be completely switched within just 30 min of US treatment. This work presents a novel approach for incorporating mechanical sensing and rapid remodeling capabilities into materials.

Synthesis of hydrophobic biopolyesters from depolymerized Pinus radiata bark suberin

Abstract The bark of Pinus radiata offers an underutilized source of high-value renewable chemicals such as extractable polyphenols and lipophilic compounds (waxes and suberin). Here, the depolymerization and extraction of suberin from P. radiata bark and its repolymerization to form novel polyesters are reported. Three different strategies were evaluated for repolymerization of the suberin monomers, with starting materials and products characterized using chemical and thermal analysis techniques. The inclusion of comonomer (1,12-dodecanediol) to provide stoichiometric balance improved the conversion, product yield, solubility and increased molecular weight. Enzymatic polymerization conditions gave the highest yield, while the highest molecular weight was achieved using titanium butoxide, demonstrating that polymerization conditions could be varied to target desired product properties. Products were hydrophobic, as shown by contact angles, ϴ ≥ 90° after 30 s. This work highlights opportunities for utilizing suberin to add value to a P. radiata bark biorefinery concept. Potential future applications include its use as a starting material for novel bio-based polymers that can serve as water-repellent surfaces and coatings, replacing established products derived from fossil resources.

Laccase-Mediated Oxidation of Phenolic Compounds from Wine Lees Extract towards the Synthesis of Polymers with Potential Applications in Food Packaging.

Laccase from Trametes versicolor was applied to produce phenolic polymeric compounds with enhanced properties, using a wine lees extract as the phenolic source. The influence of the incubation time on the progress of the enzymatic oxidation and the yield of the formed polymers was examined. The polymerization process and the properties of the polymeric products were evaluated with a variety of techniques, such as high-pressure liquid chromatography (HPLC) and gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The enzymatic polymerization reaction resulted in an 82% reduction in the free phenolic compounds of the extract. The polymeric product recovery (up to 25.7%) and the molecular weight of the polymer depended on the incubation time of the reaction. The produced phenolic polymers exhibited high antioxidant activity, depending on the enzymatic oxidation reaction time, with the phenolic polymer formed after one hour of enzymatic reaction exhibiting the highest antioxidant activity (133.75 and 164.77 μg TE mg-1 polymer) towards the ABTS and DPPH free radicals, respectively. The higher thermal stability of the polymeric products compared to the wine lees phenolic extract was confirmed with TGA and DSC analyses. Finally, the formed phenolic polymeric products were incorporated into chitosan films, providing them with increased antioxidant activity without affecting the films' cohesion.