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Applying cellulose paper on the triboelectric material is the trend of developing eco-friendly triboelectric nanogenerator (TENG). However, the researchers always pay attention to improve the triboelectric property of cellulose paper by the grafting of functional groups and the introduction of conductive or high dielectric property materials, while neglecting the effects of lignocellulose fiber composition including hemicellulose and lignin. In this work, the contents of hemicellulose and lignin were adjusted by sodium hydroxide and sodium chlorite, respectively; and the effects of hemicellulose and lignin on the triboelectric performance of cellulose paper were evaluated. The results showed that the open-circuit voltage (V OC ) and short-circuit current (I SC ) changed slightly with increasing hemicellulose contents, while the V OC and I SC values increased from 49.9 ± 0.5 V to 94.7 ± 0.7 V and 2.3 ± 0.04 μA to 4.3 ± 0.03 μA in the range of lignin contents from 0.8 ± 0.1 % to 8.9 ± 0.2 % because lignin can make the surface potential of cellulose paper more positive. The triboelectric performance was further demonstrated by driving 50 commercial LEDs and harvesting energy from human motion. This work provides a new idea for improving the triboelectric performance of cellulose paper., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Nowadays, plastics are widely used in daily life, but they pose huge threats to both the environment and human health. Therefore, it is imperative to develop green, sustainable and high-performance cellulose-based paper materials to replace plastics. A key challenge for paper-based packaging materials is the need for waterproof and oil-resistant properties. However, most current solutions rely on harmful fluorocarbon coatings or organic solvents, raising safety and environmental concerns. Herein, we present a novel waterproof and oil-resistant coating solution composed solely of polyvinyl alcohol (PVA) and bentonite (BT) nanosheets. When applied to sugarcane paper, this composite paper demonstrates excellent water resistance, with a 64 % water absorption rate, which is 48.4 % lower than untreated paper. Additionally, the composite paper exhibits high mechanical strength (tensile strength: 50.47 MPa, Young's modulus: 3.14 GPa) and superior barrier properties with a water vapor transmission rate of 4.59 g/(m 2 ·24h) and an oxygen transmission rate of 264.959 cm 3 /(m 2 ·24h·0.1 MPa). Furthermore, this composite paper shows promise in fruit preservation and holds great potential for broader applications in the food packaging industry., Competing Interests: Declaration of competing interest We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Biodegradable cellulosic mulch has been demonstrated as the promising alternative to traditional plastic mulch film in agriculture, whereas the highly hydrophilic property and poor wet strength severely restricted their practical application. Herein, a new waterproof dialdehyde cellulose (OR)-polyamide epichlorohydrin (P)-alkyl ketene dimer (A) (OR-P-A) was carefully designed as the green mulch film. The hydrogen bonds and Schiff base reaction between -CHO on dialdehyde cellulose fibers and -NH 2 on PAE reinforced the interfacial interaction of cellulosic fibers. Furthermore, the formed β-keto ester bonds of -OH on cellulose with AKD improved the water resistance of paper fiber. Compared with the pristine cellulose film, the dry and wet tensile strength of OR-P-A 2 were increased to 17 MPa and 3 MPa, respectively. Moreover, the water contact angle was increased from 25° for pristine cellulose film to 124° for OR-P-A 2 . In addition, the germination rate of cabbage seeds covered by OR-P-A 2 was similar to that of commercial polyethylene film in practical application. This strategy proposed a novel method to improve the hydrophobicity of cellulose film, which boosting the development of biodegradable mulch film and "green" agriculture., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cellulose paper is a flammable and hygroscopic material, which limits its application. In this paper, melamine-formaldehyde resin (MF) and silane coupling agents were used to microencapsulate ammonium polyphosphate (Si@MFAPP) in turn and added to the fibers suspension to prepare hydrophobic and flame-retardant cellulose paper. It was found that the surface of the ammonium polyphosphate (APP) was smooth with the water solubility of 0.24 g/100 mL. After microencapsulation with MF, the surface of MFAPP became rough, and the solubility was reduced to 0.1 g/100 mL. When further encapsulation with polysiloxanes, the surface showed significantly higher roughness, and a lotus leaf-like microspherical structure was formed. Specifically, its solubility decreased to 0.04 g/100 mL. In addition, the residual char weight of Si@MFAPP at 800 °C was increased from 25.27 % to 38.56 %. The water contact angle (WCA) of MFAPP/Pulp increased from 84.23° to 90.78°, and the limiting oxygen index (LOI) increased from 31.8 % to 34.1 %, meaning that the flame retardancy was obviously raised. The WCA of Si@MFAPP/Pulp enhanced to 96.45°, and the LOI was 34.5 %, meaning that the hydrophobicity was further raised. Therefore, Si@MFAPP significantly improved the flame-retardancy and hydrophobicity of the cellulose paper., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Simple, fast and low-cost paper-based analytical devices (PADs) have a good application prospect for point-of-care detection of GSH. However, effective immobilization of functional nanomaterials onto cellulose, as a critical factor in the construction of PADs, presents numerous difficulties and challenges., Results: In this study, we have developed an exceptionally straightforward and environmentally friendly synthetic approach by using ovalbumin (OVA) as a bio-mineralization template for the preparation of MnO 2 nanosheets. The MnO 2 nanosheets produced in the solution phase exhibited excellent intrinsic nano-enzyme activity and biodegradability. The OVA-MnO 2 nanosheets can effectively oxidize Amplex red in the absence of H 2 O 2 , enabling sensitive detection of GSH with a linear range of 5 nM-10 μM and a detection limit as low as 2.8 nM. Furthermore, we utilized this method to facilitate in situ synthesis of OVA-MnO 2 nanosheets directly on paper substrates. This approach eliminates the need for conventional stirring and centrifugation steps, greatly simplifying the fabrication process while reducing material usage and time expenditure. Characterization of the chemical composition and morphology confirmed the intimate growth of the 2D nano-enzymes on the cellulose fibers. Utilizing smartphone capabilities, the OVA-MnO 2 nanosheet-modified PAD enabled instrument-free detection of GSH, demonstrating high sensitivity (0.74 μM) and a wide linear response range (1-1000 μM)., Significance: The synthesis of MnO 2 nanosheets directly on cellulose substrates substantially streamlines the modification workflow of PADs and reduces detection costs, offering new avenues for clinical diagnostics of relevant diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Although bioplastics and paper straws have been introduced as alternatives to single-use plastic straws, their potential environmental, economic, and social impacts have not been analyzed. This study addresses this gap by designing a polylactic acid layer interface adhesion on cellulose paper-based (PLA-P) composite straws by a dip molding process. This process is simple, efficient, and scalable for massive production. Optimizing key manufacturing parameters, including ice bath ultrasonic, overlapping paper strips (2 strips), winding angle (60°), soaking time (5 min), and drying temperature (50 °C), were systematically evaluated to improve straw quality and manufacturing efficiency. PLA chains were found to deposit onto the cellulose network through intermolecular interactions to form a consistent "sandwich" structure, which can improve adhesion, water resistance, and mechanical properties. Interestingly, PLA-P straws effectively decomposed in soil and compost environments, with a 35-40 % degradation rate within 4 months. Besides, PLA-P straw residues affected seed germination and plant growth, but no significant toxic effects were detected. Further, microplastics were observed in soil and plant tissues (roots, stems, and leaves), and their possible diffusion mechanisms were explored. The results of a comprehensive life cycle assessment (LCA) and cost analysis showed that the process improvements reduced the ecological footprint of PLA-P straws and showed good prospects for commercial application. The study's findings contribute to the understanding of bioplastics and paper straws in effectively reducing environmental impact and fostering sustainable development., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

To overcome the problems of easy aggregation, poor reproducibility and homogeneity of metal nanosols, a SERS substrate with good sensitivity, homogeneity and reproducibility was designed and prepared for the detection of disease markers in urine. Silver nanocubes (Ag NCs) were firstly prepared and then dispersed in cationic cellulose (C-CNF) to form a homogeneous gel, which was dropped on a filter paper to develop a substrate with good SERS activity. This substrate combines the superior SERS properties of Ag NCs with the stability of C-CNF and has a minimum detection concentration of 10 -9  M for R6G. The homogeneity of this substrate was good and the RSD value was much <20 %. The SERS substrate was employed for the quantification of creatinine and uric acid, with linear ranges were 5 × 10 -3 -5 × 10 -7  M and 10 -2 -10 -6  M. The recoveries of creatinine and uric acid were calculated to be 98.3 % ∼ 103.12 % and 96.72 % ∼ 104.48 %, respectively, in the spike recovery experiments, with the relative standard deviations of <10 %. The experimental results show that the method can provide a scientific and reliable experimental basis for screening, condition monitoring and treatment of kidney and other diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

While plant fibers are abundant and biodegradable natural polymers, their high hydrophilicity often limits their applicability. To broaden the applicability of plant fiber materials across diverse fields, the present study employed cellulosic paper as a substrate and alkenyl succinic anhydride (ASA) as a low surface free energy material to fabricate a series of hydrophobic cellulosic papers (ASAP, ASA-P@Si, ASA-P@Ca, and ASA-P@Ti) through surface coating and physical vapor deposition of ASA. The results demonstrated that, in comparison to uncoated cellulosic paper, the coated variants exhibited significantly improved hydrophobicity. Notably, ASA-P@Si demonstrated superior hydrophobic performance with a contact angle of 140.90° and a sizing degree of 7.2 s, thereby meeting the requirements for specific fine paper grades. In contrast to the traditional ASA internal sizing process, the method in this study necessitates only approximately one-tenth of the conventional ASA internal sizing agent to achieve or even exceed the hydrophobic properties of paper attainable with ASA inter sizing process. Furthermore, the mechanism through which hydrophobic properties are conferred to paper can be elucidated by its surface roughness and low surface free energy, distinguishing it from the traditional ASA internal sizing approach., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Deacidification and structural reinforcement are critically important for the long-term preservation of paper cultural relics. In this study, a novel approach is presented to synergistically combine highly reactive vaterite-type calcium carbonate with aminopropyltriethoxysilane-modified cellulose nanofibrils (NH 2 -CNFs) for the restoration of aged paper. Employed as a deacidification agent, vaterite demonstrated superior efficacy at a low dosage in comparison with commercially available calcite-type calcium carbonate. Concurrently, the carboxylate content of NH 2 -CNFs was reduced, enhancing its hydrophobicity and thermal stability. A comprehensive characterization of both vaterite and NH 2 -CNFs was conducted using multiple analytical techniques. Upon application of this restoration system to aged paper samples, the pH and alkaline reserve were elevated to 8.05 and 0.637 mol/kg, respectively. The tensile strength of the paper sample was augmented by 15 %, while folding endurance and tearing resistance were enhanced by 139 % and 66 %, respectively. Notably, the integration of vaterite exhibited no deleterious impact on the mechanical properties of the paper substrate. Additionally, this treatment imparted a substantial anti-aging effect, as evidenced by the results of dry heat and UV-irradiation aging. Consequently, this research introduces a novel and efficacious methodology for the restoration of aged paper, offering promising implications for the conservation of historical documents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The discovery of pancreatic lipase (PL) inhibitors is an essential route to develop new anti-obesity drugs. In this experiment, chitosan was used to add amino groups to cellulose filter paper (CFP) and then glutaraldehyde was used to covalently combine PL with amino-modified CFP through the Schiff base reaction. Under optimal immobilization conditions, CFP immobilized PL has a wide range of pH and temperature tolerance, as well as excellent reproducibility, reusability and storage stability. Subsequently, 26 natural products (NPs) were screened by immobilized PL with black tea extract having the highest inhibition rate. Three compounds with binding effects on PL (epigallocatechin gallate, theaflavin-3-gallate and theaflavin-3,3'-digallate) were captured. Molecular docking proved that these three compounds have a strong binding affinity for PL. Fluorescence spectra further revealed that theaflavin-3,3'-digallate could statically quench the intrinsic fluorescence of pancreatic lipase. The molecular docking and thermodynamic parameters indicated that electrostatic interaction was considered as the main interaction force between PL and theaflavin-3,3'-digallate. Finally, the potential anti-obesity targets and pathways of the three compounds were discussed through network pharmacology. This study not only proposes a simple and efficient method for screening PL inhibitors, but also sheds light on the anti-obesity mechanism of active compounds in black tea., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cellulose paper-based composites represent a promising and sustainable alternative for electromagnetic interference (EMI) shielding applications. Derived from renewable and biodegradable cellulose fibers, these composites are enhanced with conductive fillers namely carbon nanotubes, graphene, or metallic nanoparticles, achieving efficient EMI shielding while maintaining environmental friendliness. Their lightweight, flexible nature, and mechanical robustness make them ideal for diverse applications, including wearable electronics, flexible circuits, and green electronics. This paper explores the fabrication techniques, composite properties, with particular emphasis on ways to enhance the shielding properties, and performance metrics of cellulose-based composites, highlighting their potential to replace traditional metallic materials in various EMI shielding scenarios, thus contributing to the development of eco-friendly and high-performance electronic devices. Despite advancements, challenges such as achieving uniform filler dispersion and scalability of eco-friendly production methods persist, limiting industrial application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financialinterestsor personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Anionic cellulose nanofibers (CNFs) were used to stabilize emulsions that combined water-soluble (and oil-soluble), strongly antioxidant extracts with a water-immiscible, notably antimicrobial essential oil. Specifically, the radical scavenging activity was primarily provided by aqueous extracts from olive fruit (Olea europaea L.), while the antimicrobial effects owed eminently to thyme oil (Thymus vulgaris L.). The resulting emulsions were highly viscous at low shear rate (4.4 Pa·s) and displayed yield stress. The addition of edible salts decreased the yield stress, the apparent viscosity and the droplet size, to the detriment of stability at ionic strengths above 50 mM. Once characterized, the antioxidant and antimicrobial emulsions were applied on packaging-grade paper. Coated paper sheets inhibited the growth of Listeria monocytogenes, a common foodborne pathogen, and acted as antioxidant emitters. In this sense, the release to food simulants A (ethanol 10 vol%), B (acetic acid 3 wt%), and C (ethanol 20 vol%) was assessed. A 24-hour exposure of 0.01 m 2 of coated paper to 0.1 L of these hydrophilic simulants achieved inhibition levels of the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) in the 15-29 % range. All considered, the bioactive properties of thyme essential oil towards lipophilic food products can be complemented with the antioxidant activity of aqueous olive extracts towards hydrophilic systems, resulting in a versatile combination for active food packaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

New techniques are always demanded to pursuit green and economical ways for nanocellulose preparation. We herein proposed to use γ-valerolactone (GVL) to facilitate the nanocellulose preparation from bleached bamboo pulp fibers as a green and sustainable pretreatment. The GVL pretreatment caused the bamboo fibers to destruct, resulting in an obviously increased fine fiber content, which was systematically studied to disclose the influence of different factors on the fiber changes. The optimum GVL pretreatment conditions were determined as reaction time of 4 h, reaction temperature of 140 °C and the ratio of GVL to water of 4:1. Notably, the GVL pretreatment caused negligible changes in the functional groups on cellulose, as well as its crystalline structure. The resultant nanocellulose (i.e. G-CNF) had a width of ca. 47 nm and it showed good adsorption capacity towards RR195 dye since an impressive dye uptake rate of 46.81 % was attained. The incorporation of G-CNF significantly improved the coloring performance and the ∆E (color difference) value reached up to 33.73. Improvements in the mechanical properties of RR195 dyed paper were also observed with the incorporation of G-CNF. This work sheds light on the nanocellulose preparation with GVL pretreatment and demonstrates a feasible way to apply the resultant nanocellulose in the colored paper manufacture., Competing Interests: Declaration of competing interest All the authors state that we have non-competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

User-friendly in-field sensing protocol is crucial for the effective tracing of intended analytes under less-developed countries or resources-limited environments. Nevertheless, existing sensing strategies require professional technicians and expensive laboratory-based instrumentations, which are not capable for point-of-care on-site analyses. To address this issue, artificial intelligence handheld sensor has been designed for direct reading of Ni 2+ and EDTA in food samples. The sensing platform incorporates smartphone with machine learning-driven application, 3D-printed handheld device, and cellulose paper microfluidic chip stained with ratiometric red-green-emission carbon dots (CDs). Intriguingly, Ni 2+ introduction makes green fluorescent (FL) of CDs glow but red FL fade because of the coordination of Ni 2+ with CDs verified by density functional theory (DFT), concurrently manifesting continuous FL colour transition from red to green. Subsequent addition of EDTA renders FL of CDs-Ni 2+ recover owing to the capture of Ni 2+ from CDs by EDTA based on strong chelation effect of EDTA on Ni 2+ confirmed via DFT, accompanying with a noticeable colour returning from green to red. Inspired by above FL phenomena, CDs-based cellulose paper microfluidic chips are first fabricated to facilitate point-of-care testing of Ni 2+ and EDTA. Designed fully-automatic handheld sensor is utilized to directly output Ni 2+ and EDTA concentration in water, milk, spinach, bread, and shampoo based on wide linear ranges of 0-48 μM and 0-96 μM, and low limits of detection of 0.274 μM and 0.624 μM, respectively. The proposed protocol allows for speedy straightforward on-site determination of target analytes, which will trigger the development of automated and intelligent sensors in near future., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Shaomin Shuang reports that funding was provided by National Natural Science Foundation of China. Bianxiang Zhang reports that funding was provided by Central Guidance Local Science and Technology Development Fund Project. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The work was aimed at evaluating the adsorptive properties of waste newspaper (WN) activated carbons chemically produced using sodium salts for methylene blue (MB) and congo red (CR) removal. The activated carbons, designated as AC1, AC2, AC3 and AC4 were prepared through impregnation with NaH 2 PO 4 , Na 2 CO 3 , NaCl and NaOH, respectively and activation at 500 °C for 1 h. The activated carbons were characterized for surface chemistry, thermal stability, specific area, morphology and composition. The AC1 with a surface area of 917 m 2 /g exhibits a greater MB capacity of 651 mg/g. Meanwhile, a greater CR capacity was recorded by AC2 at 299 mg/g. The pseudo-second order model fitted well with the kinetic data, while the equilibrium data could be described by Langmuir model. The thermodynamic parameters, i.e.., positive ΔH°, negative ΔG° and positive ΔS° suggest that the adsorption of dyes is endothermic, spontaneous and feasible at high solution temperature. To conclude, WN is a potential cellulose source for producing activated carbon, while NaH 2 PO 4 activation could be employed to convert WN into activated carbon for effective dye wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Due to intrinsic defect of fire hazard security, improving the flame retardant capacity of paper is still insufficient in case of precombustion. Herein, we integrate the flame retardant with flame detection performance on the surface of paper, the restricts of graphene oxide (GO) are overcome between high thermoelectric performance and flexibility. A flexible lamellar thermoelectric composite (GO-LA-HP) is constructed through the co-assembly of GO, ascorbic acid (LA), and phenoxycycloposphazene (HP), lamellar GO-LA-HP avoid GO's toughness decline after modification, but also enhance fire sensitivity and flame resistance. The composite could significantly decrease the temperature rise stage (<150 °C), and trigger the fire-warning within 2 s. The hybrid coating composed of phytic acid/phosphoric acid (PyA/PA) and modified thermoelectric GO-LA-HP becomes excellent compatibility on the surface of the modified paper (GPP). GPP is able to extinguish itself immediately after leaving the fire in the vertical combustion, and display the excellent flame resistance. Furthermore, GPP's alarm signal could be timely generated as little as 3 s of contacting the flame, and the response time can exceed 600 s. According to the structure observation and analysis, the related synergistic fire detection reinforcing and flame-retardant mechanisms are also proposed and clarified., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

In this work, shellac and its crosslinking were studied to produce paper straws for the application of liquid products. Commercial paper straws are not durable for liquid foods due to their hygroscopic nature, and thus, they find it challenging to replace single-use plastics. Shellac is a naturally occurring resin utilized as an adhesive and water-resistant coating over the paper straw. Shellac was cured at 125 °C, 150 °C, 175 °C, and 200 °C, and it was crosslinked in about 210 min, 150 min, 60 min, and 30 min respectively and studied for kinetics. The crosslinking of shellac produced a thermally stable material. Compared to commercial paper straws, these paper shellac straws exhibited high bending stiffness (1356.11 Nmm), tensile strength (13,74 MPa), flexural strength (21.72 MPa), and compression strength (24.99 MPa). Moreover, the paper shellac straws didn't bend in wet conditions under load for up to one day, while the commercial paper straw bends in 8 min. Therefore, paper straws with shellac can replace plastic-based straws for a sustainable future., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Arihant Ahuja reports financial support was provided by the Prime Minister Research Fellowship, Ministry of Education, India. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cellulose fibers(CFs)-based electrode materials are of considerable interest for future wearable electronic devices due to excellent flexibility and strength, and hydrophilicity. The effective introduction of electrode materials into CFs is essential for flexible supercapaciotors(SCs). A tunable electrochemical performance of conductive polymers for poly(3,4-ethylenedioxythiophene)(PEDOT) has been aroused great interests. Herein, we design its electrochemical process via sodium anthraquinone-2-sulfonate(AQS) as dopant and electrolyte additive to construct active electrode interior and interface. As a result, the PEDOT@CFs electrode exhibits great increase of doping level from 0.16 to 0.29, conductivity from 353.46 to 626.15 S m -1 , and specific capacitance from 140.22 to 1211.57 F g -1 at a current density of 0.2 A g -1 . Furthermore, the PEDOT:AQS@CFs electrode possess excellent cyclic stability (96.01 %) after 1000 cycles. The work reveals the mechanism of AQS as dopant and electrolyte additive, and provides a new perspective for application of PEDOT in energy storage field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

MOF-199 is considered to be an excellent CO 2 adsorbent owing to its substantial specific surface area, suitable pore structure and abundant sorption sites. However, powdered MOF-199 is prone to agglomeration and has poor recyclability. Herein, we proposed a MOF-199-based adsorbent by combining the MOF synthesis process with traditional papermaking process. Through such a design, MOF-199 particles are adhered on the surface of wood pulp fiber. The sufficient hydroxyl groups and electrostatic forces of cellulose facilitates the homogeneous and tight adhesion of MOF crystals. The optimal MP-4 sample demonstrated a high CO 2 adsorption capacity (1.80 mmol·g --1 at 25 °C) and good CO 2 /N 2 selectivity (30.06). Moreover, the composite sorbent can be easily regenerated. The adsorption mechanism was analyzed by the density functional theory approach. The simulation results showed that the carboxyl functional groups with a large number of oxygen atoms and active metal sites are the key to boost the CO 2 adsorption performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The growing interest in paper-based materials for packaging is driven by their renewable and eco-friendly characteristics. However, their poor barrier performance against water, oil, and gas limits their application in the food packaging industry. In this study, we developed a simple dual-layer coating method to create water- and oil-repellent, gas barrier, antioxidant, and antibacterial paper-based materials using naturally-derived materials, including chitosan (CS), ethyl cellulose (EC), and cascade biorefinery products from green walnut husk (GWHE and CNC). The bottom CS/CNC oil-resistant coating and the top EC/GWHE water-resistant coating were applied to the paper surface. The synergistic effect of these coatings enhances the gas barrier and imparts functional properties to the paper. Compared to uncoated paper, the dual-layer-coated paper demonstrated a 239.1 % increase in tensile index, a higher kit rating value of 12/12, a lower Cobb 60 value of 3.21 mg/m 2 , a 44.0 % decrease in water vapor permeability (WVP), and a 90.7 % reduction in air permeability (AP). Additionally, this coated paper exhibited good antioxidant and antibacterial properties and favorable biodegradability. This study provides novel insights into the valorization of GWH waste and presents a sustainable strategy for producing high-performance paper-based materials for food packaging applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

To optimize the imbalance between the interfacial bonding and porosity properties of carbon paper (CP) caused by phenol formaldehyde resin (PF) impregnation, and therefore improve the performance of proton exchange membrane fuel cells (PEMFCs), a new approach through cellulose nanofibers grafted with methyl methacrylate (CNFM) as a modified reinforcement and pore-forming agent for PF is investigated. Through suppressing the methylene backbone fracture of CNFM-modified PF during its thermal depolymerization, the interfacial bonding between PF matrix carbon and carbon fibers is enhanced. Compared with unmodified CP, the in-plane resistivity of CNFM-modified CP is reduced by 35.78 %, while the connected porosity increases to 82.26 %, and more homogeneous pore size distribution (PSD) in the range of 20-40 μm is obtained for CNFM-modified CP. Besides, the tensile strength, flexural strength, and air permeability of CNFM-modified CP increase by 72.78 %, 298.4 %, and 103.97 %, respectively. In addition, CNFM-modified CP achieves the peak power density of PEMFCs to 701.81 mW·cm -2 , exhibiting 10.98 % improvement compared with commercial CP (632.39 mW·cm -2 ), evidently achieving an integral promotion of CP and comprehensive performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Accurately identifying and quantifying toxicants is crucial for medico-legal investigations in forensic toxicology; however, low analyte concentrations and the complex samples matrix make this work difficult. Therefore, a simplified sample preparation procedure is crucial to streamline the analysis to minimize sample handling errors, reduce cost and improve the overall efficiency of analysis of toxicants. To address these challenges, an innovative disposable in-tip cellulose paper (DICP) device has been developed for the extraction of three pesticides viz. Chlorpyrifos, Quinalphos and Carbofuran from postmortem blood samples. The DICP device leverages cellulose paper strips housed within a pipette tip to streamline the extraction process, significantly reducing solvent usage, time, and labor while maintaining high analytical accuracy. The extraction of pesticides from postmortem blood using the DICP device involves a streamlined process characterized by adsorption and desorption. The diluted blood samples were processed through the DICP device via repeated aspirating and dispensing calyces to adsorb the pesticides onto the cellulose paper. The adsorbed pesticides are then eluted using acetone, which is collected for GC-MS analysis. The method was meticulously optimized, achieving a limit of quantification in the range of 0.009-0.01 µg mL -1 . The intra-day and inter-day precisions were consistently less than 5 % and 10 %, respectively, with accuracy ranging from 94-106 %. Relative recoveries for the analytes were observed to be between 60 % and 93.3 %, and matrix effects were determined to be less than 10 %. The method's sustainability was validated with a whiteness score of 98.8, an AGREE score of 0.64, a BAGI score of 70 and ComplexMoGAPI score of 77. Applicability was demonstrated through successful analysis of real postmortem blood samples and proficiency testing samples, highlighting its potential utility in forensic toxicology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The success of polymerase chain reaction (PCR) depends on the quality of deoxyribonucleic acid (DNA) templates. This study developed a cost-effective and eco-friendly DNA extraction system utilizing poly(3,4-dihydroxyphenylalanine)-modified cellulose paper (polyDOPA@paper). PolyDOPA@paper was prepared by oxidatively self-polymerizing DOPA under weak alkaline conditions and utilizing the adhesive property of polyDOPA on different materials. Compared to the uncoated cellulose paper, polyDOPA coating significantly enhances DNA adsorption owing to its abundant amino, carboxyl, and hydroxyl moieties. The DNA extraction mechanism using polyDOPA@paper was discussed. The maximum adsorption capacity of polyDOPA@paper for DNA was 20.7 μg cm -2 . Moreover, an automated extraction system was designed and fabricated using 3D printing technology. The device simplifies the operation and ensures the reproducibility and consistency of the results. More importantly, it eliminates the need for specialized training of operators. The feasibility of the polyDOPA@paper-based automated extraction system was evaluated by quantitatively detecting Escherichia coli in spiked milk samples via a real-time PCR. The detection limit was 10 2 cfu mL -1 . The results suggest that the system would have significant potential in detecting pathogens., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Due to the common contamination of multiple mycotoxins in food, which results in stronger toxicity, it is particularly important to simultaneously test for various mycotoxins for the protection of human health. In this study, a disposable immunosensor array with low-cost was designed and fabricated using cellulose paper, polydimethylsiloxane (PDMS), and semiconducting single-walled carbon nanotubes (s-SWCNTs), which was modified with specific antibodies for mycotoxins AFB1 and FB1 detection. The strategy for fabricating the immunosensor array with two individual channels involved a two-step protocol starting with the form of two kinds of carbon films by depositing single-wall carbon nanotubes (SWCNTs) and s-SWCNTs on the cellulose paper as the conductive wire and sensing element, followed by the assembly of chemiresistive biosensor with SWCNTs strip as the wire and s-SWCNTs as the sensing element. After immobilizing AFB1-bovine serum albumin (AFB1-BSA) and FB1-bovine serum albumin (FB1-BSA) separately on the different sensing regions, the formation of mycotoxin-BSA-antibody immunocomplexes transfers to electrochemical signal, which would change with the different concentrations of free mycotoxins. Under optimal conditions, the immunosensor array achieved a limit of detection (LOD) of 0.46 pg/mL for AFB1 and 0.34 pg/mL for FB1 within a wide dynamic range from 1 pg/mL to 20 ng/mL. Furthermore, the AFB1 and FB1 spiked in the ground corn and wheat extracts were detected with satisfactory recoveries, demonstrating the excellent practicality of this established method for simultaneous detection of mycotoxins., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The aging of paper seriously threatens the service life of cultural heritage documents. Bacterial cellulose (BC), which has a good fiber aspect ratio and is rich in hydroxyl groups, is suitable for strengthening aged paper. However, a single BC added was not ideal for paper restoration, since only strengthening was not able to resist the persistent acidification of ancient book. In this work, BC was functionalized by 3-aminopropyltriethoxysilane (APTES) to develop the interface bonding with aged paper. Fourier transform infrared (FTIR), X-ray diffraction (XRD), nuclear magnetic resonance (NMR) and elemental analysis identified the successful amino-silanization of BC. The modification parameters were optimized as the concentration of APTES of 5 wt%, the reaction time of 4 h, and the reaction temperature of 80 °C based on a considerable improvement in the strength properties without obvious appearance impact on reinforced papers. Moreover, the pH value of the repaired paper was achieved at 8.03, ensuring the stability of the anti-aging effect. The results confirmed that APTES-BC had great potential applications in ancient books conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. All the authors listed have approved the manuscript enclosed., (Copyright © 2024. Published by Elsevier B.V.)

Electromagnetic hydrogels have attracted significant attention due to their vast potential in soft robotics, biomedical engineering, and energy harvesting. To facilitate future commercialization via large-scale industrial processes, we present a facile concept that utilizes the specialized knowledge of papermaking to fabricate hydrogels with multifunctional electromagnetic properties. The principles of papermaking wet end chemistry, which involves the handling of interactions among cellulosic fibers, fines, polymeric additives, and other components in aqueous systems, serves as a key foundation for this concept. Notably, based on these principles, the versatile use of chemical additives in combination with cellulosic materials enables the tailored design of various products. Our methodology exploits the unique hierarchically pitted and hollow tube-like structures of papermaking grade cellulosic fibers with discernible pits, enabling the incorporation of magnetite nanoparticles through lumen loading. By combining microscale softwood-derived cellulosic fibers with additives, we achieve dynamic covalent interactions that transform the cellulosic fiber slurry into an impressive hydrogel. The cellulosic fibers act as a skeleton, providing structural support within the hydrogel framework and facilitating the dispersion of nanoparticles. In accordance with our concept, the typical hydrogel exhibits combined attributes, including electrical conductivity, self-healing properties, pH responsiveness, and dynamic rheologic behavior. Our approach not only yields hydrogels with interesting properties but also aligns with the forefront of advanced cellulosic material applications. These materials hold the promise in remote strain sensing devices, electromagnetic navigation systems, contactless toys, and flexible electronic devices. The concept and findings of the current work may shed light on materials innovation based on traditional pulp and paper processes. Furthermore, the facile processes involved in hydrogel formation can serve as valuable tools for chemistry and materials education, providing easy demonstrations of principles for university students at different levels., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Developing plastic/fluorine/silicon-free and degradable water/oil-resistant coatings for paper-based packaging materials to replace disposable plastic products is a very effective way to solve the problem of 'white pollution' or microplastics pollution. A novel water/oil-resistant coating was developed by alkyl ketene dimer (AKD)-based Pickering emulsion and chitosan in this work. Cellulose nanofibrils (CNF) were used as a stabilizing solid for AKD emulsion, with the addition of chitosan as an oil-resistance agent. The coating provides excellent hydrophobicity, water/oil resistance as well as good barrier properties. The water contact angle was as high as 130° and the minimum Cobb60 value was 5.7 g/m 2 , which was attributed to the hydrophobicity of AKD. In addition, the kit rating reached maximum 12/12 at coating weight of 8.26 g/m 2 and the water vapor transmittance rate (WVTR) was reduced to 153.4 g/(m 2 ⋅day) at the coating weight of 10.50 g/m 2 . The tensile strength of the paper was increased from 28.1 to 43.6 MPa after coating. Overall, this coating can effectively improve the performance of paper-based materials, which may play an important role in the process of replacing disposable plastic packaging with paper-based materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Counterfeiting has caused great concern all over the world. What's more, the fluorescent materials play an important role in technological research and development for high-security. In this work, lead-metal-organic framework (Pb-MOF) and perovskite (MAPbBr 3 ) were used in papers to achieving fluorescence counterfeiting. Pb-MOF, as the template or precursor of MAPbBr 3 , were in-situ generated on the surface of cellulose fibers (CFs) to preparing into hand sheets (Pb-MOF@CFs). Through the analysis of experimental results, it was found that ligands, reaction systems, addition sequences of drugs, time, etc. would affect the deposition of Pb-MOF on the surface of CFs. Using CH 3 NH 3 Br (MABr) as the anti-counterfeiting ink to write on Pb-MOF@CFs, the orange writing leaped across the paper, which caused by Pb in Pb-MOF chemically reacting with MABr forming MAPbBr 3 . The orange writing displayed green fluorescence under 365 nm ultraviolet lamp excitation. The orange writing with green fluorescence could be extinguished and reconstructed, which had promise for reuse. In addition, fluorescent security papers (MAPbBr 3 @Pb-MOFs@CFs) were prepared by immersing Pb-MOF@CFs in MABr solution. The fluorescence of MAPbBr 3 @Pb-MOFs@CFs opened when the surface of it was scraped under 365 nm ultraviolet lamp. This unique fluorescence property was very important in improving the security of products. Consequently, the ongoing research on perovskite and MOFs materials is of great significance., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The demand for paper-based packaging materials as an alternative to incumbent disposable petroleum-derived polymers for food packaging applications is ever-growing. However, typical paper-based formats are not suitable for use in unconventional applications due to inherent limitations (e.g., excessive hydrophilicity, lack antimicrobial ability), and accordingly, enabling new capabilities is necessity. Herein, a simple and environmentally friendly strategy was proposed to introduce antimicrobial and hydrophobic functions to cellulose paper through successive chemical grafting of 3-aminopropyltriethoxysilane (APS) and cinnamaldehyde (CA). The results revealed that cellulose paper not only showed long-term antibacterial effect on different bacteria, but also inhibited a wide range of fungi. Encouragingly, the modified paper, which is fluorine-free, displays a high contact angle of 119.7°. Thus, even in the wet state, the modified paper can still maintain good mechanical strength. Meanwhile, the multifunctional composite papers have excellent biocompatibility and biodegradability. Compared with ordinary cellulose paper, multifunctional composite paper can effectively prolong the shelf life of strawberries. Therefore, the multifunctional composite paper represents good application potential as a fruit packaging material., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Sustainable strategies to improve the water resistance of cellulose paper are actively sought. In this work, polymeric microspheres (PMs), prepared through emulsion polymerization of cellulose nanofibers stabilized rubber seed oil-derived monomer, were investigated as coatings on corrugated medium paper (CMP). After infiltrating porous paper with PMs, the water-resistant corrugated papers (WRCP n ) with enhanced mechanical properties were obtained. When 30 wt% PMs were introduced, WRCP 30 turned out to be highly compacted with an increased water contact angle of 106.3° and a low water vapor transmission rate of 81 g/(m 2 d) at 23 °C. Meanwhile, the tensile strength of WRCP 30 increased to 22.2 MPa, a 4-fold increase from CMP. When tested in a well-hydrated state, 71% of its mechanical strength in the dry state was maintained. Even with a low content of 10 wt% PMs, WRCP 10 also exhibited stable tensile strength and water wettability during the cyclic soaking-drying process. Thus, the plant oil based sustainable emulsion polymers provide a convenient route for enhancing the overall performance of cellulose paper., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Over the centuries, various types of paper have been produced, each characterized by a different ratio of natural macromolecules, mainly lignin and cellulose. Handmade paper has a higher content of cellulose with respect to the early machine-made paper, where lignin is the other important component. Microorganisms are able to colonize and deteriorate both types. They can release on their surfaces pigments and colorants which produced anesthetic stains. To better understand the microbiota colonizing these stains, 17 samples were analyzed, from both handmade and machine-made paper surfaces, as well as library and archive environments. Combination of microbiological and high-throughput sequencing (HTS) approaches were applied. The culture-dependent methodology comprised: isolation, DNA identification, hydrolytic and paper staining assays. The HTS was performed by MinION platform and for the mycobiome a more suitable bioinformatics analysis pipeline, MetONTIIME based on QIIME2 framework, was applied. The paper model staining assay permitted the direct recognition of colorizing isolates which in combination with sequencing data evidenced a complex microbial community able to stain the two types of paper. Staining abilities were confirmed by frequently isolated and detected fungi as well as newly discovered ones Roussoella euonymi and Achaetomium. We have also evidenced the staining ability of several bacteria., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Bio-based additives received significant attention in pulp and paper properties improvement. For this, the most cited biochemical Cellulose Nano Fibrils (CNFs) and Cationic Starch (CS) were experimentally compared with the most declared synthetic chemical, Cationic Polyacrylamide (CPAM). SEM images showed better paper surface filling by the utilization of the chemicals. The three studied polymers, in solely or combination mechanism, improved mainly bagasse pulp and paper properties compared to the blank sample, except for pulp drainage, which decreased by CNFs to lower volumes presumably due to its intrinsic characteristics. Cationic polymers (CP) compared to CP/CNFs approaches increased pulp retention and drainage but decreased paper density and strengths. The best pulp retention and drainage achieved by CS followed by CPAM, while paper air persistency, density, and strength properties evaluated highest by CP/CNFs followed by CNFs. Generally, CS revealed a more significant improvement in pulp and paper properties than CPAM either with or without CNFs., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Radiometric assays have widely been used for measuring protein kinase activity for decades. In addition, several non-radiometric kinase assay formats have been developed over the years, including luciferase-based and fluorescence-based assays. However, radiometric assays are still considered as the "gold standard" for protein kinase assays, because of their direct readout, high sensitivity, reproducibility, reliability, and very low background signals. These radiometric assays rely on P81 phosphocellulose paper to capture the phosphorylated substrate and wash out unreacted [γ- 32 P] ATP. However, recently the production of P81 was discontinued by the manufacturer, causing major concern within the protein kinase research community. The advantages of radiometric assays over other kinase assay methods call for an urgent alternative to the discontinued P81 paper. In this report, we demonstrate that the LSA-50 paper is a worthy alternative for radiometric protein kinase assays originally using P81 phosphocellulose paper., (Copyright © 2021. Published by Elsevier Inc.)

In this study, we developed an in-package colorimetric paper to monitor the ripeness of kiwifruit by detecting the release of aldehydes. Strongly hydrophobic composite films were prepared using chitosan as the matrix and beeswax as an additive. A piece of cellulose paper containing methyl red and bromocresol violet as color indicators was heat-sealed between two hydrophobic films to protect the indicators from the effects of fruit respiration and transpiration. The nucleophilic addition reaction between aldehydes and OH - (Cannizzaro reaction) changes the pH in the paper and triggers a color change in the indicators. As the kiwifruit ripens, the colorimetric paper changes from bluish-purple to dark red and then gradually to red. A mobile phone application was further used to measure the RGB values and link them to kiwifruit ripeness. This intelligent paper can be used for the accurate and convenient monitoring of produce in real time., (Copyright © 2021 Elsevier B.V. All rights reserved.)

While current trends in Green Analytical Chemistry aim at reducing or simplifying sample treatment, food usually comprises complex matrices where direct analysis is not possible in most cases. In this context, sample treatment plays a pivotal role. Biogenic amines are naturally formed in many foodstuffs due to the action of microorganisms, while their presence has been associated with adverse health effects. In this work, the extraction of seven biogenic amines (cadaverine, histamine, phenylethylamine, putrescine, spermidine, spermine, and tyramine) from beer samples has been simplified using laboratory filter paper as sorbent without any further modification. The analysis of the eluates by direct infusion mass spectrometry reduces the time of analysis, increasing the sample throughput. This simple but effective method enabled the determination of the analytes with limits of detection as low as 0.06 mg L -1 and relative standard deviations better than 11.9%. The suitability of the method has been assessed by analyzing eight different types of beers by the standard addition method., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests or personal relationships that could have influenced in any way the work developed in this article., (Copyright © 2021. Published by Elsevier B.V.)

Paper-TiO 2 -Ag 2 O floating photocatalysts were produced under mild condition and their photocatalytic activity for the degradation of aromatic amine under sunlight stimulant was investigated. Characterizations by Raman, XRD, XPS, DRS and PL confirmed the presence of TiO 2 and Ag 2 O, and the morphology of the appended TiO 2 /Ag 2 O layer was probed by FE-SEM. The photocatalytic activity of the prepared samples was investigated by the degradation of aniline (AN) in water under simulated sun-light illumination and constrained conditions, i.e. non-stirring and non-oxygenation. The presence of Ag 2 O combined with TiO 2 was shown to improve the resistance of paper to bacteria attack, thus increasing the durability of the photocatalyst. Thanks to its hydrophobic character, the paper-TiO 2 -Ag 2 O NPs can be employed as useful floating photocatalyst and can be reused in continuous cycles., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Packaging is as important as the product itself because it is a crucial marketing and communication tool for business. Oxidized nanocellulose (ONC), extracted from agriculture residues of bagasse raw material using ecofriendly ammonium persulfate hydrolysis method, is used as support/reducing agent for the generation of silver nanoparticles (AgNPs) via photochemical procedure and reinforcing element in paper functionalization. The natural polymer, sodium alginate (SA) is exploited to enhance the binding of the ONC-AgNPs over cellulose fibers. The SA/ONC-AgNPs bio-nanocomposite is incorporated on paper matrix, which represents a more suitable choice respect to other substrates for its renewable, biocompatible, biodegradable, and cost-effective properties. Structural and antimicrobial evaluations show that the papers embedded with the SA/ONC-AgNPs possess good mechanical, thermal, barrier and antibacterial properties., Competing Interests: Declaration of competing interest There is no conflict of interest in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Hydrophobization of cellulosic materials and particularly paper products is a commonly used procedure to render papers more resistant to water and moisture. Here, we explore the hydrophobization of unsized paper sheets via the gas phase. We employed three different compounds, namely palmitoyl chloride (PCl), trifluoroacetic anhydride/acetic anhydride (TFAA/Ac 2 O)) and hexamethyldisilazane (HMDS) which were vaporized and allowed to react with the paper sheets via the gas phase. All routes yielded hydrophobic papers with static water contact angles far above 90° and indicated the formation of covalent bonds. The PCl and TFAA approach negatively impacted the mechanical and optical properties of the paper leading to a decrease in tensile strength and yellowing of the sheets. The HMDS modified papers did not exhibit any differences regarding relevant paper technological parameters (mechanical properties, optical properties, porosity) compared to the non-modified sheets. XPS studies revealed that the HMDS modified samples have a rather low silicon content, pointing at the formation of submonolayers of trimethylsilyl groups on the fiber surfaces in the paper network. This was further investigated by penetration dynamic analysis using ultrasonication, which revealed that the whole fiber network has been homogeneously modified with the silyl groups and not only the very outer surface as for the PCl and the TFAA modified papers. This procedure yields a possibility to study the influence of hydrophobicity on paper sheets and their network properties without changing structural and mechanical paper parameters., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

In this work, cellulose filter paper (CFP), which is inexpensive and commercially available, was used as the carrier, and the immobilized α-glucosidase was obtained by two steps: firstly, the surface of CFP was modified by polydopamine/polyethyleneimine (PDA/PEI) co-deposition method to obtain CFP-PDA/PEI with a uniform coating of rich positive charge; subsequently, α-glucosidase was immobilized on the CFP-PDA/PEI by electrostatic adsorption. The free enzyme and immobilized enzyme have the same optimal temperature (70℃) and pH (8.0), and their K m is similar, which is 2.2 and 2.8, respectively. These results show that the immobilization process does not change the properties of the enzyme greatly. The immobilized enzyme still maintains 75.6% of its initial activity after 10 repeated uses, showing good reusability. The excellent repeatability (RSD = 2.2%, n = 5) and the verification of competitive inhibitor (acarbose) illustrates the reliability of the immobilized enzymes for enzyme inhibitor screening. Finally, combined with CE, a screening method based immobilized α-glucosidase was proposed and applied to screen the α-glucosidase inhibitory from 10 kinds of Traditional Chinese medicines (TCMs) in vitro. The results indicated that the method was a very effective tool for screening potential α-glucosidase inhibitors from TCMs., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Nanofibrillated cellulose (NFC), a promising bio-based nanomaterial, has received much attention in the field of coating preparation due to its unique properties. Herein, NFC was prepared from microcrystalline cellulose (MCC) via high-pressure homogenization process and deliberately employed as coating agent to enhance the properties of paper coatings and coated paper. The results demonstrated that the obtained paper coatings exhibited strong NFC concentration dependence on rheological behavior and displayed decreased water retention value with the increased NFC addition. Meanwhile, NFC addition was found to lead to the reduced Cobb value, improved air resistance, and enhanced tensile strength of coated paper. Under an optimized NFC addition of 0.30-0.40%, the properties of coated paper generally reached the optimum state. Moreover, SEM observation further confirmed that NFC addition imparted a relatively uniform surface structure to coated paper. Hence, NFC could be defined as an effective coating agent for developing high-performance coated paper for food packaging applications., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Starch and derivatives thereof have proven their usefulness in paper coating processes. Among these derivatives, cationic starch has been widely used in the paper industry as a flocculation, dispersion and ink fixing agent. In another context, nanoscale cellulosic materials have been shown to improve the strength, retention of fillers, the barrier properties of packaging paper products, and printing qualities. This review summarizes the recent studies on the general components used in paper coating, describes the conventional and alternative synthetic processes of cationic starches and nanocellulose, and deals with their current and potential applications in papermaking, focusing primarily on surface treatments. Moreover, environmental applications have been considered to expand the understanding and usefulness of these materials. Further research on modified polysaccharides is encouraged to replace, in a feasible way, petro-based components of coating formulations, and to provide paper surfaces with new properties., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this work, we prepared novel cellulosic paper by incorporating tannin into the kraft pulp for potential application in active food packaging. The kraft pulp fibers were firstly periodate oxidized to obtain the dialdehyde cellulosic fibers, and then reacted with varied dosages of tannin to incorporate them into the fibers by covalent bondings between aldehyde groups on cellulose and active hydrogen on tannin. Handsheets were prepared using the tannin incorporated fibers through papermaking process and the properties were characterized. The percentage of tannin in the paper increased with the increase of the tannin dosage. FT-IR spectra confirmed the successful incorporation of tannin into the cellulosic fibers. It was found that paper after incorporation of tannin turned to be surface hydrophobic with contact angles higher than 90°, which may probably due to the covalent bonds between tannin and cellulose. The handsheets show high antioxidative and UV-shielding properties, which both increased with the increase of the tannin percentage in the paper. Water vapor transmission rate (WVTR) decreased after the incorporation of tannin, and this could facilitate its application in food packaging. The breaking length of tannin incorporated paper decreased insignificantly, less than 10% with the tannin percentage as high as 45%., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Chitosan with low (25 kDa) and high molecular weight (2100 kDa) were used to enhance performances of paper made from steam-exploded bamboo fibers and nanofibrillated cellulose. Chitosan solutions with concentrations of 0-1.0 wt% were manually applied on paper surface using a facile coating approach with a wire bar. Effects of chitosan coatings on morphology, thermal stability, wettability, mechanical performances and antibacterial properties of the paper were investigated. The larger improvement in the mechanical properties and wettability of the chitosan coated paper was observed with increasing concentrations of chitosan due to the disappearance of empty pores between fibers within a cellulose network by the formed chitosan matrix. These improvements were significantly higher when high molecular weight chitosan was applied. Yet, the addition of chitosan slightly decreased the thermal stability of the coated paper, and the chitosan coating did not improve the antimicrobial properties of the paper. The antimicrobial activity of chitosan against Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) was found to be diminished when a chitosan solution was entrapped within paper. Together with the overall migration of the paper in food simulants, the results suggested that the chitosan coated paper could be applied for non-food-direct-contact packaging materials., (Copyright © 2019 Elsevier B.V. All rights reserved.)

China, a big paper-making country, produced hundreds of millions of tons of waste paper which contain a lot of fiber every year. Cellulose nanocrystals were extracted from recycled waste paper which can be a high value utilization of secondary fiber. In this paper, cellulose nanocrystals were successfully extracted from waste paper fibers via two different systems, sulfuric acid hydrolysis (SCNCs) and one-step ammonium persulfate (APS) oxidation (OCNCs). This not only broadened the methods of extracting CNCs from waste paper, but also improved the dispersion and reactivity of CNCs. The CNCs products were investigated by FT-IR spectroscopy for functional group structure, X-ray diffraction for crystal structure, TG-DTG for thermal stability and scanning electron microscope, transmission electron microscope for morphology. The results showed that both OCNCs and SCNCs were a rod-like structure. The crystallinity of OCNCs and SCNCs increased to 72.45 and 77.56, but with a low yield of 22.42% and 41.22%, respectively. The result also suggested H 2 O 2 formed by decomposition of APS, selectively oxidized the hydroxyl on the C 6 in cellulose to carboxyl, introduced 0.57 mmol/g carboxyl. Successful preparation of CNCs extracted from waste paper can effectively utilize the fiber resources in waste paper, thus transforming into higher economic benefits., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Cellulose paper-chitosan (CC) double-layer films containing epsilon-poly-l-lysine (ε-PL) (0.5 and 1% w/v) were developed. FTIR analysis showed a strong association between the ε-PL and CC film. Antimicrobial activity against Listeria monocytogenes was investigated both in vitro and in the chicken breast meat. The CC films without ε-PL showed no antimicrobial activity, while the addition of ε-PL induced significant (p < 0.05) effects. During the 28 days of storage at 4  ° C, no significant difference was found on the anti-listeria activity of films. When storage temperature was raised from 4 to 22  ° C, the antimicrobial activity was reduced. Films containing 1% ε-PL exhibited 1.5 log 10  CFU/g reduction in L. monocytogenes population during 12 days storage of meat at 4  ° C, while no significant reduction was found in CC films with 0.5% ε-PL (p > 0.05). This study revealed an antimicrobial activity for CC films impregnated with ε-PL, to control foodborne pathogens in meat., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Flexible plasmonic Surface-enhanced Raman scattering (SERS) substrates were fabricated using cellulose textile fibers, in which the textile fibers were recycled from waste paper in an eco-friendly way. The Glycidyltrimethylammonium chloride (GTAC) with positive charges was grafted onto the surface of the cellulose textile fibers through cationization. Plasmonic silver nanoparticles (Ag NPs) with negative charges were decorated onto the cellulose textile fibers via electrostatic interactions. After cationization, the variation range of the diameter of the cellulose textile fibers was significantly increased because part of the cellulose was dissolved under alkaline condition, leading to more 'hot spots' for SERS during the shrinking process. The cellulose textile fiber-Ag NPs nanocomposite was employed for monitoring bisphenol A (BPA) in water and soft drink by SERS and the sensitivity of BPA detection achieved 50 ppb. The recovery values of BPA in soda water samples were from 96% to 105%. These results illustrate that the cellulose textile fiber-Ag NPs nanocomposite can be used as flexible, high sensitivity SERS substrates for detecting harmful ingredients in food or environment., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The current work describes the development of a "nanopaper-based analytical device (NAD)", through the embedding of curcumin in transparent bacterial cellulose (BC) nanopaper, as a colorimetric assay kit for monitoring of iron and deferoxamine (DFO) as iron-chelating drug in biological fluids such as serum blood, urine and saliva. The iron sensing strategy using the developed assay kit is based on the decrease of the absorbance/color intensity of curcumin-embedded in BC nanopaper (CEBC) in the presence of Fe(III), due to the formation of Fe(III)-curcumin complex. On the other hand, releasing of Fe(III) from Fe(III)-CEBC upon addition of DFO as an iron-chelating drug, due to the high affinity of this drug to Fe(III) in competition with curcumin, which leads to recovery of the decreased absorption/color intensity of Fe(III)-CEBC, is utilized for selective colorimetric monitoring of this drug. The absorption/color changes of the fabricated assay kit as output signal can be monitored by smartphone camera or by using a spectrophotometer. The results of our developed sensor agreed well with the results from a clinical reference method for determination of Fe(III) concentration in human serum blood samples, which revealed the clinical applicability of our developed assay kit. Taken together, regarding the advantageous features of the developed sensor as an easy-to-use, non-toxic, disposable, cost-effective and portable assay kit, along with those of smartphone-based sensing, it is anticipated that this sensing bioplatform, which we name lab-on-nanopaper, will find utility for sensitive, selective and easy diagnosis of iron-related diseases (iron deficiency and iron overload) and therapeutic drug monitoring (TDM) of iron-chelating drugs in clinical analysis as well., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The present study delineates the preparation, characterization, and application of (3-Aminopropyl)triethoxysilane (APTES)/Caprine liver-derived extracellular matrix (CLECM) coated paper matrix for cell delivery. Here, we exploited positively charged surface of the paper matrix (as imparted by APTES derivatization) to improve the biological responses of the cells. Our results demonstrated that the functionalized paper matrixes favored the adhesion, growth, and proliferation of multiple cell types including normal, transformed, cancerous, and stem cells as compared to the pristine paper matrix. Upon implantation into the mice model, the developed paper matrix supported infiltration of the host cells and vasculature without showing any evidence of significant systemic toxicity. Moreover, the cells cultured on the paper matrix, when delivered to the CAM and mouse models, showed an enhanced vascular network around the substrate, thereby confirming its potential to deliver the cells in vivo. Together, the study confirms that the reported paper-based platform is easy to fabricate, cheap, portable and could efficiently be applied to cell delivery applications for either tissue repair or the development of humanized animal model., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Herein, we introduce a nanopaper-based analytical device (NAD) or "lab-on-nanopaper" device for visual sensing of human serum albumin (HSA) in human blood serums, which relies on embedding of curcumin within transparent bacterial cellulose (BC) nanopaper. BC nanopaper is an appropriate candidate to be an excellent platform for the development of optical (bio)sensors due to having exceptional properties such as optical transparency, high flexibility, porosity, biodegradability, and printability. The hydrophilic test zones were created on the fabricated bioplatform through creating the hydrophobic walls via laser printing technology. The color changes of curcumin embedded in BC nanopaper (CEBC) due to the inhibitory effect of HSA on the curcumin degradation in alkaline solutions, which can be monitored visually (naked eye/Smartphone camera) or spectroscopically using a spectrophotometer, were linearly proportional to the HSA concentration in the range of 10-300 μM and 25-400 μM, respectively. The developed NAD/CEBC as a novel albumin assay kit was successfully utilized to the determination of HSA in human blood serum samples with satisfactory results. Building upon the fascinating features of BC nanopaper as a very promising bioplatform in optical (bio)sensing applications we are confident "lab-on-nanopaper" devices/NADs, which take the advantages of the nanopaper and also meet the ASSURED criteria, could be considered as a new generation of optical (bio)sensing platforms that are currently based on paper, glass or plastic substrates., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The current research intended to explore the hardwood pulps capabilities to produce cellulose (CNPs) and lignocellulose nanopapers (LNPs) and feasible enhancement of their performance for possible utilization in sustainable packaging. The high-yield hardwood pulps were then bleached to show the fundamental role of residual lignin on the ultrafine fibrillation processes, structural and barrier properties of nanopapers. X-ray diffraction results demonstrated that the crystallinity and crystallite size of CNPs and LNPs were lower than the corresponding starting pulps. Field emission scanning electron microscopy analysis showed that the average nanofibril diameter of the CNPs and LNPs are 35 nm and 23 nm, respectively. Elastic modulus of LNPs was found to be 9.1 and 10.8 GPa for Chemimechanical and Neutral sulfite semichemical pulps, respectively. The semi-porous and consolidated structure of LNPs prepared from CMP fibers contributed to yield the lowest water vapor transmission rate i.e. 108 g/m 2 .day which is promising for potential applications in packaging materials., (Copyright © 2019 Elsevier B.V. All rights reserved.)