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Glucose detection is critical for diabetes diagnosis and management. This study aimed to develop an enzyme-free, cascade-based, triple-readout paper sensor utilizing bismuth (Bi)-based metal-organic frameworks/gold nanoparticles (Bi-BDC-NH 2 @Au) for detecting urine glucose. Herein, Bi-BDC-NH 2 @Au exhibited glucose oxidase-like activity and oxidized glucose to generate H 2 O 2 , which then quenched the blue fluorescence of FP@Bi-BDC-NH 2 @Au through an inner filter effect. Additionally, owing to its pronounced peroxidase-like activity, Bi-BDC-NH 2 @Au catalyzed H 2 O 2 to produce ·OH, which oxidized colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized TMB (oxTMB), thereby increasing the system temperature owing to the excellent photothermal conversion properties of oxTMB. These mechanisms enabled the triple-readout of glucose levels. Quantification in the fluorescence and colorimetric modes was achieved through a Python-based image recognition algorithm that accurately read B/(R + G + B) values, and the photothermal mode relied on a portable infrared thermal imager to monitor temperature changes. The detection limits for the fluorescence, colorimetric, and photothermal modes were 4.2, 3.3, and 5.7 μM, respectively. The self-calibration ability of the sensor across different modes markedly enhanced its detection accuracy and robustness. The developed sensor successfully has detected and quantified urine glucose, effectively distinguishing between healthy individuals and patients with diabetes, providing a convenient and efficient tool for diabetes management., 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 food and pharmaceutical sectors frequently utilize vanillin (VAN), a food ingredient with a pleasing flavor and aroma. However, excessive consumption of VAN causes several health problems, including liver and kidney damage, headaches, skin conditions, nausea, and vomiting. To prevent health problems, it is crucial to identify and control the amount of VAN in food and drugs. Here, we have synthesized carboxymethyl hexanoyl chitosan (CHC), a water-soluble polymer, that has been extensively studied through surface morphological and optical characterizations. Furthermore, because of their affordability, ease of use, and simple manufacturing processes, disposable paper electrodes (PPE) offer several benefits in biosensors. Therefore, to detect VAN electrochemically, CHC has been drop-coated on a PPE. High catalytic activity for the electro-oxidation of VAN in phosphate buffer solution (PBS; pH 7.4) is demonstrated by the CHC-coated PPE. The electrochemical sensor demonstrated the limit of detection (LOD) of 29 nM (S/N = 3), and the peak current for VAN was found to be linear to the concentration ranges between 7.8 μM and 200 μM under ideal conditions. Additionally, in the presence of VAN at 200 μM, the in-house developed sensor demonstrated non-interference towards glucose, citric acid, ascorbic acid, sucrose, and Cu 2+ at higher concentrations (400 μM). Nonetheless, real sample analysis of commercial VAN (with and without) ice-cream demonstrated the successful detection of the analyte, which further authenticates the potential of the sensor in real world applications. The current study provides a novel method for detecting industrially relevant analytes upon specific CHC based surface modifications of the sensor., 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.)

Porous silicon (PSi) thin films on silicon substrates have been extensively investigated in the context of biosensing applications, particularly for achieving label-free optical detection of a wide range of analytes. However, mass transport challenges have made it difficult for these biosensors to achieve rapid response times and low detection limits. In this work, we introduce an approach for improving the efficiency of molecule transport in PSi by using open-ended PSi membranes atop paper substrates in a flow-through sensor scheme. The paper substrate provides structural support as well as an efficient means of draining solutions from the PSi membrane without the use of an external pump and microfluidic channels. Distinct changes in the reflectance properties of the PSi membrane are measured when molecules are captured in the membrane. A concentration-dependent response of the sensor for protein detection is demonstrated. Factors influencing the interaction time of molecules in the PSi membrane and the drying time of the membrane, which directly affect the detection sensitivity and overall testing time, are discussed. The demonstrated performance of the PSi-on-paper sensor establishes the feasibility of a platform for low-cost rapid diagnostic tests with a highly sensitive, quantitative readout.

Succinic acid is applied in many chemical industries in which it can be produced through microbial fermentation using lignocellulosic biomasses. Mixed-waste office paper (MWOP) containing lignocellulosic fibers is enormously generated globally. MWOP is recycled into toilet paper and cardboard, but the recovery process is costly. The reuse of MWOP to alternatively produce succinic acid is highly attractive. In this study, pretreatment of MWOPs with 1% ( v / v ) H 2 SO 4 at 121 °C for 20 min was found to be optimal. The optimal conditions for the enzymatic hydrolysis of H 2 SO 4 -pretreated MWOP (AP-MWOP) were at 50 °C, with cellulase loading at 80 PCU/g AP-MWOP. This resulted in the highest glucose (22.46 ± 0.15 g/L) and xylose (5.11 ± 0.32 g/L). Succinic acid production via separate hydrolysis and fermentation (SHF) by Escherichia coli KJ122 reached 28.19 ± 0.98 g/L (productivity of 1.17 ± 0.04 g/L/h). For simultaneous saccharification and fermentation (SSF), succinic acid was produced at 24.58 ± 2.32 g/L (productivity of 0.82 ± 0.07 g/L/h). Finally, succinic acid at 51.38 ± 4.05 g/L with yield and productivity of 0.75 ± 0.05 g/g and 1.07 ± 0.08 g/L/h was achieved via fed-batch pre-saccharified SSF. This study not only offers means to reuse MWOP for producing succinic acid but also provides insights for exploiting other wastes to high-value succinic acid, supporting environmental sustainability and zero-waste society.

Timely monitoring of circulating tumor DNA (ctDNA) in serum is meaningful for personalized diagnosis and treatment for lung cancer. Cheap and efficient point-of-care testing (POCT) has emerged as a promising method, especially in a low-resource setting. Herein, (i) a 3D pop-up paper-based POCT device was designed and manufactured via a cheap method; it was used for saving time and efficiently building a biosensor; (ii) a novel cobalt boride nanosheet (CoB NS) nanozyme with abundant groups was used for POCT dual-mode signal transduction and then a portable smartphone/pressure meter to readout; (iii) a user-friendly smartphone app was fabricated for achieving more convenient POCT. Detailly, the dual-mode signal generated was based on the CoB NS with peroxidase activity to catalyze a chromogenic agent to develop color and with catalase activity to catalyze decomposition of H 2 O 2 to O 2 . Density functional theory (DFT) and experimental results showed a good catalysis performance of the CoB NS via studying its five possible catalytic pathways, in which the metal Co is the catalytic active site center that acts as the electron donor and promotes electron transfer between the CoB NS and the adsorbed substrates. Benefiting from that, the proposed method showed good analytical ability in detecting ctDNA. Besides, its accuracy was valued by comparing it with the standard qPCR method to detect real samples from tumor cells and tumor-bearing mice, which showed a consistent result and potential practical applicability of the proposed method for POCT ctDNA. In general, this work not only provided a dual-mode POCT platform that could also be applied for other analytes but also first revealed the nanozyme properties of the CoB NS and inspired its new application from electrocatalysis, energy, etc. to biomedicine.

Using a laser-scribed (direct printing) technique, we have fabricated an enzymeless, mediatorless, and paper-interfaced electrochemical device (P-LSG) for uric acid detection on a flexible polyimide sheet. Various paper substrates were investigated, and it was found that Whatman filter paper-1 is promising to obtain the best electrochemical signals at the small volume of electrolyte, i.e., 20 μL. Furthermore, the Whatman filter paper-1 was modified with gold nanoparticles (AuNPs) to improve the electrocatalytic activity of the P-LSG device. The fabricated AuNP-modified P-LSG biosensor exhibited excellent electrocatalytic activity for the detection of uric acid over a wide range of 10 to 750 μM, with sensitivity of ∼0.214 μA μM -1 cm -2 , and a limit of detection of ∼1.4 μM. The sensor was further validated by using the UHPLC-ESI-MS/MS technique, and the observed percentage recovery was less than 10%. This work opens the window to modified paper substrates with various nanomaterials to improve the sensing parameters. The electrolyte storage capacity and rich chemistry of paper additionally provide an efficient immobilization platform for biorecognition elements to diagnose other metabolites. Furthermore, it has the potential to analyze the volume of small samples (like sweat, tears, urine, etc.) using paper to develop noninvasive wearable biosensors.

Mercury ions (Hg 2+ ) are highly toxic heavy metals that are commonly found in natural environments. Owning to their non-biodegradability and accumulation in the food chain, the precise detection of trace amounts of Hg 2+ is essential for preventing chronic accumulation and ensuring food safety. In this study, we present a dual-mode paper sensor for simultaneous colorimetric and Surface-Enhanced Raman Spectroscopy (SERS) detection of Hg 2+ in tea, achieving ultrasensitive, rapid, and on-site screening. 4-Mercaptopyridine (4-MPY) was effectively chemisorbed onto the gold nanoparticles (AuNPs), acting as a signal probe for colorimetric methods. Moreover, it can produce plasmonic hot spots for SERS by interacting with the pyridine ring. To enhance the signal intensity of both colorimetry and SERS, a silver shell is in-situ grown on the surface of AuNPs captured on the paper sensor by reduction of Ag + , achieving signal amplification. The visual limit of detection (LOD) for the colorimetric biosensor is 2.5 pM, while the LOD of SERS is 0.48 pM with this dual-mode paper sensor. The sensitivity of both the colorimetric method and SERS was improved by approximately 200 and 500 times, respectively, with the designed signal amplification strategy. The system allows for multiple parallel screening of the same sample, ensuring accurate results without any false-positive or false-negative. This study provides a valuable platform for the accurate detection of various other heavy metal ions and provides effective strategies for improving the performance of colorimetric methods., 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 Ltd. All rights reserved.)

Accurately monitoring the freshness of high-protein foods has significant implications for both food safety and public welfare. Since a large amount of hydrogen sulfide (H 2 S) is produced during spoilage-related processes, abnormal H 2 S levels are often considered an important indicator of food spoilage. Therefore, we synthesized novel nanoparticles (NPs) containing Silicon (Si) dots and CdTe quantum dots to accurately assess the amount of sulfide ions (S 2- ) and thus the quality of high-protein foods in the early stage of storage. As the concentration of S 2- increased, the fluorescence intensity of Si/CdTe NPs at λ em  = 488 nm increased, while the fluorescence intensity at λ em  = 620 nm was quenched. The fluorescence intensity ratio (F 620 /F 488 ) was negatively linearly correlated to S 2- concentrations in the range of 1-20 μM, with a detection limit of 0.3 μM. Furthermore, to achieve portable detection, we mixed Si/CdTe NPs with sodium carboxymethyl cellulose to prepare effective visual fluorescent sensing paper chips, which exhibited ideal porous structure, good particle dispersion, and excellent fluorescence properties. Incubating the paper chips with high-protein foods allowed for accurate monitoring of food freshness during storage. Therefore, this approach provided a reliable and portable method to determine H 2 S concentration using a novel concept to ensure the freshness and safety of high-protein foods., 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.)

In 2023, we published a research article in the Journal of Colloidal and Interface Science, based on our experimental findings and substantiating scaling arguments leading to a simple theoretical insight on the effect of red blood cell (RBC) aggregation on the wicking behaviour of a finite volume of blood as it navigates through the porous passages of a paper matrix (Laha et al., 2023). Of late, we received comments from Li (2024), which offered certain suggestions regarding the possible improvement of the capillary bundle model as considered in our article for analyzing the transport of blood through the paper pores. Herein, we provide a detailed discussion on each of the points raised by Li (2024) and rationalize our views in further details in addition to the contents already provided in our concerned article., 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 Inc. All rights reserved.)

This research investigates the pulp and paper industry's transition to sustainability by valorizing unused roadside and natural grasses for paper production. Large-scale production from residual grass poses multifaceted challenges, requiring collaboration across stakeholders, from biomass collection to manufacturing. To understand key drivers and barriers within this complex system, experts from various fields, including local farmers, researchers, policymakers, and industry executives were interviewed, leading to the development of a Fuzzy Cognitive Map (FCM). The analysis explores various scenarios to assess how socio-economic, technological, and political factors influence the transition to low-carbon practices. These scenarios highlight the effects of varying levels of technology development, economic conditions, and policy support on the transition's progress and outcomes. Results show that the system is highly sensitive to shifts in socio-economic and political conditions. Political interventions play a crucial role, especially during energy crises and increased public demand for sustainable solutions. Grass-based paper production is seen as a viable pathway, but challenges such as the economic feasibility of emerging technologies remain. We recommend targeted policies to improve the economic viability of grass-based products and optimize biomass allocation between energy and bio-based products, ensuring a more balanced and sustainable transition., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

This study aims to provide evidence that when testing cellulose paper modified with copper particles (CuPs), the particle size and the analysis method influence the antimicrobial activity observed by this material. Commercial CuPs of nanometric size (2.7 nm, CuNPs) and micrometric size (2.5 µm, CuMPs) were used to modify cellulose paper sheets. CuPs were incorporated during the pulp disintegration phase (stage 1) of the sheet formation process, according to the ISO 5269-1:2005 standard. Modified paper sheets retained 16% and 14% of CuNPs and CuMPs, respectively. Additionally, CuPs were distributed randomly on the fiber surfaces, often forming aggregates. Finally, the antimicrobial activity of the modified paper sheets was evaluated using ISO 20645:2004 and ISO 20743:2013. The results showed that the antimicrobial activity assessed using each standard method is conditioned by the mechanism of action of the CuPs and, therefore, by their size. It was concluded that ISO 20645:2004 is suitable for evaluating the antibacterial effect of paper/CuNPs, as nanoparticles diffuse from the paper and are released into the culture medium. In contrast, ISO 20743:2013 can be used for both CuNP- and CuMP-based paper, as it evaluates the antibacterial effect based on the direct interaction between the copper particle and the bacteria., Competing Interests: The authors declare no conflicts of interest.

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.)

The development of high-performance specific sensors is promising for the rapid detection of harmful residues in animal-derived foods. Recently, luminescent metal-organic framework/molecularly imprinted polymer (LMOF/MIP) materials have been developed as ideal candidates for the analysis of harmful residues. Here, we reported a simple fabrication protocol of paper-based chip through in-situ growth of LMOF on a negatively charged modified filter paper, a paper-based molecularly imprinting layer (FP@BA-Eu@MIP) was thereafter successfully prepared via the boronate affinity-based controllable oriented surface imprinting strategy. The paper-based chips obtained were used to construct a rapid test strip of tetracycline (TC). After addition of TC, significant fluorescence changes on the surface of the FP@BA-Eu@MIP paper-based chip could be observed from blue to red via inner filter effect and photo-induced electron transfer under the excitation of 360 nm. The adsorption kinetics was explored in detail. The presented strip exhibited satisfied selectiveness and sensitivity with a limit of detection of 8.47 μg L -1 for TC. It was confirmed that LMOF/MIP as a biomimetic recognition module can play a crucial role in enrichment and fluorescence response. This study provided a real application case for an in-situ fabricated fluorescence paper-based chip in rapidly detecting harmful residues., 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 practical applications of grass plastic mulch films are limited because their residues turn into microplastics and enter the food chain. This study solves this problem by preparing a degradable cellulose-lignin-waterborne polyurethane composite grass paper film. First, waterborne polyurethane prepared using a mild method was composited with lignin via an addition reaction and the formation of hydrogen bonding between the -OH groups of lignin and the -NCO and -OH groups of polyurethane. Finally, the as-prepared polyurethane-lignin composite was applied as a coating on the surface of a paper-based material to prepare a grass paper mulch film. The relationship between lignin content and the molecular weight, thermal stability, mechanical properties, polymer network crosslinking density, antioxidant capability, and light transmittance of the coating was studied, revealing that higher lignin contents considerably improved the barrier and mechanical properties of the coating and grass paper mulching film. In particular, a lignin content of 20 % resulted in a grass paper mulching film with outstanding grass pressing performance and degradability. Therefore, the multifunctional, ecofriendly grass paper mulch film prepared from cellulose-lignin-waterborne polyurethane composite materials provides an innovative approach to solve the pollution problem of traditional grass plastic paper mulch., 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.)

A molecularly imprinted polymer (MIP) has been synthetized, characterized, impregnated on paper, and integrated into a 3D printed platform with smartphone-based fluorescent detection for the determination of tetracycline in water samples. The MIP synthesis was performed by precipitation polymerization, which was subsequently deposited onto a glass microfiber paper. The synthesized polymer and the MIP@paper have been characterized by FTIR spectroscopy, scanning electron microscopy, and EDS spectroscopy. Afterward, a 3D printed detection platform that houses monochromatic LED strips as radiation source and a smartphone as detector have been used for determination of tetracycline. Digital image processing was based on the RGB colour model using image J software and the red intensity channel was used as analytical signal due to its higher sensitivity. Several factors that affect the adsorption capacity and fluorescent detection have been optimized. Under optimum conditions, detection limit of 0.04 mg L -1 and good linearity up 5 mg L -1 (r = 0.998), were achieved. The intra- and inter-day precision of 4.9 and 7.2 %, respectively, expressed as relative standard deviation (%RSD) were obtained, showing the good precision of the proposed methodology. Satisfactory recoveries between 87 and 98 % were obtained spiking real water sample matrices at different concentrations (0.1-0.3 mg L -1 ). The portable 3D platform with smartphone-based fluorescent detection exploiting all-in-one spot test method for tetracycline using MIP@paper was evaluated with AGREE and GAPI metrics, evidencing its environmentally friendly approach. Furthermore, the BAGI tool demonstrated the practicality of the method, in terms of functionality and applicability compared to previous HPLC and spectrofluorometric methods., 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 improvement of food safety and the reduction of food loss and waste require the development of new bioanalytical tools that provide chemical information about the composition of food that is of great value for improving traceability and extending the shelf life of food. Herein, a Cu-based metal-organic framework has been synthesized and immobilized onto cellulose paper disks for colorimetric and fluorescent detection and quantification of biogenic amines in food. The color of the nano metal-organic framework changes from green to brown in the presence of low amounts of biogenic amine vapors. Also, the fluorescence emission of the nano metal-organic framework greatly decreases after exposing the cellulose disks to amine vapors. The developed sensing paper disk exhibits a quick response to the presence of volatile biogenic amines, very low detection limits, and great selectivity. Also, the paper sensor was used for real-time monitoring of biogenic amines in bass samples at different temperature conditions, being a highly valuable method for evaluating food freshness and safeguarding food safety., 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.)

Plastics and paper are common components of municipal solid waste (MSW), making an in-depth understanding of their interactions essential for MSW thermal conversion. In this study, the co-pyrolysis behavior of plastic and paper was investigated. Firstly, the thermal decomposition characteristics were analyzed. Secondly, the pyrolytic behavior was elucidated in a fixed-bed reactor. Thirdly, the impact of plastic melting on co-pyrolysis was clarified. Results indicated that the thermal decomposition was accelerated between 250 °C and 283 °C, while temperatures above 400 °C resulted in inhibition. During fixed-bed pyrolysis, char yields (70.7-16.9 %) were increased by 4.0 %-12.7 %. This increase was mainly due to plastic melting, which contributed 8.6 % and increased aliphatic carbon content. Besides, PVC and PET exhibited a broader melting range > 500 °C. Bio-oil yields (25.5-70.6 %) were reduced by 3.4 %-12.4 %, primarily affecting aliphatic compositions. Gas yields (3.8-6.5 %) were reduced < 400 °C but increased with temperature, involving primarily H 2 , CH 4 , C 2 H 4 , and C 2 H 6 ., 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 Ltd. 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: Taking notes during learning has benefits both during class (through writing things down to encode information) and after class (by using written notes as external storage for revision). Comparisons of note-taking methods (i.e., using paper or a computer) have mainly shown that paper leads to better learning. However, previous studies have mostly been conducted in laboratory contexts. Aims: The current study investigates university students' perceptions of the efficacity of their own preferred note-taking method, along with the strategies they employ. Sample: Data were collected from 108 university students. Methods: Students answered a questionnaire about their note-taking strategies during initial note-taking (in class) and revision (after class). Results: The results show that students who take notes on paper do not consider their method to be more effective, but they report engaging in more reformulation and less multitasking. Students who take notes on a computer are more likely to reformat their notes, and thus to reformulate at a later stage. For all students, review sheets are mostly done on paper. Conclusions: These results suggest that although students are not necessarily aware of the benefits of reformulation associated with handwriting on paper during initial note-taking, when revising, they tend to choose handwriting and benefit from reformulation when aiming for deeper processing. Therefore, revision activities remain mainly paper-based.