Modified Cellulose Fibers Research Articles

Environmental modification of cellulose fibers for reducing dye diffusion rate by anionic polyacrylamide

Reactive dyeing is the primary method for coloring cellulose fibers due to its vibrant colors, various hues, excellent colorfastness, and cost-effectiveness. However, this process consumes a large amount of water and chemicals, leading to significant environmental concerns due to the wastewater. Non-aqueous media/less water dyeing has emerged as a cleaner alternative, showing promising results in dyeing cotton fibers with reactive dyes. Nevertheless, the rapid adsorption rate of dyes can impact the evenness of dyeing. This study explores the use of anionic polyacrylamide (APAM) in the modification bath to reduce dye adsorption rate and enhance dye desorption during cellulose fibers dyeing. Fourier transform infrared spectroscopy (FT-IR) and field-emission scanning electron microscope (FSEM) analysis revealed effective interaction between APAM and cellulose fibers. Thermal gravimetric analysis (TGA), X-ray diffraction (XRD), and breaking strength tests indicated minimal impact on the thermal stability and physical properties of cellulose fibers with APAM modification. Zeta potential testing demonstrated that APAM modification reduced the surface potential of cellulose fibers and increased their negative charge. The adsorption rate of reactive dye decreased with APAM modification, while dye fixation, washing, and rubbing fastness remained largely unaffected. Adsorption isotherm results supported the weakening of the affinity between dyes and fibers after APAM treatment. Furthermore, the electrostatic potentials of fibers decreased after APAM modification. Compared to salt-free dyeing in non-aqueous media dyeing systems, anionic polymer modification not only improves the level dyeing performance of cotton fiber and reduces 0.9% in dyeing costs, but also increases production efficiency.

The impact of the carbohydrate-binding module on how a lytic polysaccharide monooxygenase modifies cellulose fibers

BackgroundIn recent years, lytic polysaccharide monooxygenases (LPMOs) that oxidatively cleave cellulose have gained increasing attention in cellulose fiber modification. LPMOs are relatively small copper-dependent redox enzymes that occur as single domain proteins but may also contain an appended carbohydrate-binding module (CBM). Previous studies have indicated that the CBM “immobilizes” the LPMO on the substrate and thus leads to more localized oxidation of the fiber surface. Still, our understanding of how LPMOs and their CBMs modify cellulose fibers remains limited.ResultsHere, we studied the impact of the CBM on the fiber-modifying properties of NcAA9C, a two-domain family AA9 LPMO from Neurospora crassa, using both biochemical methods as well as newly developed multistep fiber dissolution methods that allow mapping LPMO action across the fiber, from the fiber surface to the fiber core. The presence of the CBM in NcAA9C improved binding towards amorphous (PASC), natural (Cell I), and alkali-treated (Cell II) cellulose, and the CBM was essential for significant binding of the non-reduced LPMO to Cell I and Cell II. Substrate binding of the catalytic domain was promoted by reduction, allowing the truncated CBM-free NcAA9C to degrade Cell I and Cell II, albeit less efficiently and with more autocatalytic enzyme degradation compared to the full-length enzyme. The sequential dissolution analyses showed that cuts by the CBM-free enzyme are more evenly spread through the fiber compared to the CBM-containing full-length enzyme and showed that the truncated enzyme can penetrate deeper into the fiber, thus giving relatively more oxidation and cleavage in the fiber core.ConclusionsThese results demonstrate the capability of LPMOs to modify cellulose fibers from surface to core and reveal how variation in enzyme modularity can be used to generate varying cellulose-based materials. While the implications of these findings for LPMO-based cellulose fiber engineering remain to be explored, it is clear that the presence of a CBM is an important determinant of the three-dimensional distribution of oxidation sites in the fiber.

Investigating Cellulose Binding of Peptides Derived from Carbohydrate Binding Module 1.

Carbohydrate-binding modules (CBM) have emerged as useful tools for a wide range of tasks, including the use as purification tags or for cellulose fiber modification. For this purpose, the CBM needs to be attached to a target protein leading to large constructs. We investigated if short peptides from the carbohydrate binding site of CBMs can bind in a similar way as native, full-length CBMs to nanocrystalline cellulose (NCC) or cotton linter paper. We designed our cellulose-binding peptides to be less hydrophobic and shorter than those previously reported. Starting from the binding site of Cel7A-CBM1, we incorporated the essential amino acids involved in cellulose binding into our peptides. These peptides, as well as control peptides with scrambled sequences or a lack of essential amino acids, bound to cellulose with similar affinity as CBM regardless of their secondary structure, sequence, or hydrophobicity. This unspecific mode of cellulose binding displayed by the presented peptides may be exploited to functionalize cellulose-based biomaterials by means of peptide-conjugates.

Sugarcane Bagasse: Challenges and Opportunities for Waste Recycling

Sugarcane has primarily been used for sugar and ethanol production. It creates large quantities of residual lignocellulosic biomass such as sugarcane bagasse, leaves, tops, and vinasse. Biomass is a sustainable prospect for biorefineries aiming to optimize production processes. We detail recent research developments in recycling sugarcane, including energy generation and pyrolysis to obtain biofuels, for example. To produce biochar, the energy cost of operating at high temperatures and large-scale production remain as obstacles. The energy generation prospects can be enhanced by pellet production; however, it requires an improvement in quality control for long-term storage or long-distance transportation. In civil construction, the materials still need to prove their long-term efficiency and reliability. Related to adsorbent materials, the use of sugarcane bagasse has the advantage of being low-cost and environmentally friendly. Nevertheless, the extraction, functionalization, and modification of cellulose fibers, to improve their adsorption properties or even mode of operation, still challenges. The synthesis of nanostructures is still lacking high yields and the ability to scale up. Finally, controlling dispersion and orientation and avoiding fiber agglomeration could improve the mechanical response of composites using sugarcane bagasse. The different possibilities for using sugarcane and its residues reinforce the importance of this material for the industry and the global economy. Thus, the present work addresses current challenges and perspectives of different industrial processes involving sugarcane aiming to support future research on waste-derived subjects.

Innovative modification of cellulose fibers for paper-based electrode materials using metal-organic coordination polymers

Cellulosic paper-based electrode materials have attracted increasing attention in the field of flexible supercapacitor. As a conductive polymer, polyaniline exhibits high theoretical pseudocapacitive capacitance and has been applied in paper-based electrode materials along with cellulose fibers. However, the stacking of polyaniline usually leads to poor performance of electrodes. In this study, metal-organic coordination polymers of zirconium-alizarin red S and zirconium-phytic acid are applied to modulate the polyaniline layer to obtain high-performance cellulosic paper-based electrode materials. Zirconium hydroxide is firstly loaded on cellulose fibers while alizarin red S and phytic acid are introduced to regulate the morphology of polyaniline through doping and coordination processes. The results show that the introduction of dual coordination polymers is effective to regulate the morphology of polyaniline on cellulose fibers. The performances of the paper-based electrode materials, including electrical conductivity and electrochemistry, are apparently improved. It provides a promising strategy for the potential development of economical and green electrode materials in the conventional paper-making process.

Bio-based adsorption foam composed of MOF and polyethyleneimine-modified cellulose for selective anionic dye removal

With the increase of sustainable development goal, the bio-based adsorption materials with high and selective dye removal are important for water treatment in the dyeing industry. In this paper, a bio-based adsorption foam composed of metal-organic frameworks (MOF) and polyethyleneimine (PEI)-modified cellulose was prepared by a three-step process, i.e., PEI modification of cellulose fibers (PC), MOF decoration of PEI-modified cellulose (MIL-53@PC), and in-situ foaming with polyurethane. PEI modification provides cellulose fiber with more active sites for both dye adsorption and MOF bonding. We found that MIL-53 crystals were tightly bonded on the surface of PC through hydrogen bonding. Because of the abundant adsorption sites (e.g., amines, iron oxide group), the MIL-53@PC demonstrated high adsorption capacity and selectivity for anionic dye (e.g., 936.5 mg/g for methyl orange) through electrostatic interaction and hydrogen bonding. Finally, MIL-53@PC particles were blended with a waterborne polyurethane prepolymer to prepare a three-dimensional hydrophilic foam (MIL-53@PC/PUF), which not only maintained high adsorption capacity and selectivity of MIL-53@PC and also improved its recyclability and reusability. The MIL-53@PC/PUF offers a promising solution for dye wastewater treatment.

Oxidation of cellulose fibers using LPMOs with varying allomorphic substrate preferences, oxidative regioselectivities, and domain structures

Lytic polysaccharide monooxygenases (LPMOs) are excellent candidates for enzymatic functionalization of natural polysaccharides, such as cellulose or chitin, and are gaining relevance in the search for renewable biomaterials. Here, we assessed the cellulose fiber modification potential and catalytic performance of eleven cellulose-active fungal AA9-type LPMOs, including C1-, C4-, and C1/C4-oxidizing LPMOs with and without CBM1 carbohydrate-binding modules, on cellulosic substrates with different degrees of crystallinity and polymer chain arrangement, namely, Cellulose I, Cellulose II, and amorphous cellulose. The potential of LPMOs for cellulose fiber modification varied among the LPMOs and depended primarily on operational stability and substrate binding, and, to some extent, also on regioselectivity and domain structure. While all tested LPMOs were active on natural Cellulose I-type fibers, activity on the Cellulose II allomorph was almost exclusively detected for LPMOs containing a CBM1 and LPMOs with activity on soluble hemicelluloses and cello-oligosaccharides, for example NcAA9C from Neurospora crassa. The single-domain variant of NcAA9C oxidized the cellulose fibers to a higher extent than its CBM-containing natural variant and released less soluble products, indicating a more dispersed oxidation pattern without a CBM. Our findings reveal great functional variation among cellulose-active LPMOs, laying the groundwork for further LPMO-based cellulose engineering.

PH-Dependent Non-enzymatic Glucose Detection with Pt/Cu2O Electrodes: Insights from Electrochemical Studies and Matrix Adaptation with Modified Cellulose Fibers.

pH-Dependent Non-enzymatic Glucose Detection with Pt/Cu2O Electrodes: Insights from Electrochemical Studies and Matrix Adaptation with Modified Cellulose Fibers.

Dual-chromic cellulose paper modified with nanocapsules containing leuco dye and spiropyran derivatives: A colorimetric portable chemosensor for detection of some heavy metal cations

Heavy metal cations are important in our daily life and may cause serious disorders and diseases. Colorimetric portable cellulosic sensors with high selectivity and sensitivity toward metal cations are preferred relative to those based on small molecules which operate mostly in organic media and difficult test methods. Here, dual-chromic stimuli-responsive cellulose paper (TPL@T-Cell) was produced by modification of the paper with the designed and prepared epoxy-functionalized polyacrylic nanocapsules via dip-coating and subsequent heat treatment processes. The capsules contained thermochromic leuco-dye derivative and photochromic hydroxyl-functionalized spiropyran and were prepared through semi-continuous miniemulsion polymerization. Chemical structure of the synthesized dyes, nanocapsules and modified cellulose fibers were identified by FTIR and UV-Vis analyses. Spherical morphology of the prepared nanocapsules with average particles size of 121 nm were observed by SEM and DLS analyses. The effective wetting of the cellulose fibers by nanocapsules with proper diffusion and deposition through the establishment of physical and chemical interactions were evaluated by SEM and ATR-FTIR analyses, respectively. The prepared TPL@T-Cell sensor revealed distinct color changes toward Fe2+, Pb2+ and Sn2+ ions. Opto-chemical results indicated that detection limit of TPL@T-Cell for Sn2+ (0.0028 µM, 0.326 ppb), Fe2+ (0.0013 µM, 0.15 ppb), and Pb2+ (0.0023 µM, 0.268 ppb) are lower than their critical permitted levels announced by WHO. These exhibited applicability of TPL@T-Cell sensor for determining trace amount of some heavy metal ions with instant responsivity, wide linear detection range, high sensitivity, and low detection limit via colorimetric and spectroscopic responses.

Harnessing total chemical-free paper and packaging materials barrier properties by mechanical modification of cellulosic fibers for food security and environmental sustainability

Surging interest in finding sustainable alternatives for single-use plastics has galvanized research into cellulosic fiber-based paper and packaging materials. This investigation examines mechanical (refining & calendering) approaches to enhance paper's barrier properties comprising Southern bleached hardwood kraft (SBHK) and Southern bleached softwood kraft (SBSK) fibers. With increased refining intensity followed by calendering, paper thickness decreases while the apparent density increases. The refining process also generates more fibrils and fines, as reflected by reduced pulp freeness. Air resistance increases significantly due to denser fiber networks and reduced porosity. Refining also improves the water vapor transmission rate (WVTR) and oil & grease resistance (OGR). A 48 % reduction in WVTR and a Kit "9″ rating for OGR were observed in SBHK paper sheets refined at 16000 revolution. Notably, refining modifies cellulose fiber morphology, promoting 59 % and 94 % external fibrillation in SBSK and SBHK fibers, respectively. This change facilitates a more compact fiber arrangement, enhancing barrier properties. XRD patterns show an initial increase in cellulose crystallinity with refining, decreasing at a higher revolution of refining. SEM analysis reveals decreased surface roughness and pore fraction post-calendering, enhancing air and OGR. In a relative sense, hardwood fibers showed higher barrier performance than softwood fibers. Our work demonstrates mechanical modifications of fibers and paper web can effectively tune paper barrier performance such as WVTR, OGR, and air/oxygen resistance.

Effects of Modified Cellulose Fiber and Nanofibril Integration on Basic and Thermo-Mechanical Properties of Paper

This study investigates the influence of fiber modification methods and beating degrees on the properties of paper sheets. Two different methods were used to modify fibers: NaOH + urea and TEMPO ((2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl) and blended with traditional paper fibers. Subsequently, we evaluated the resulting sheets for their optical, strength, and thermo-mechanical characteristics. Notably, we also scrutinized sheets created exclusively with 100% TEMPO-modified fibers. The addition of modified fibers led to improvements in several strength properties, but it had a noteworthy negative impact on the optical properties of TEMPO-treated fibers compared to the other papers. Furthermore, thermal analysis revealed that the contraction rates of the samples increased considerably up to 40–50 °C for the out-of-plane direction and surpassed 130 °C for the in-plane direction. In general, the inclusion of modified fibers had a significant effect on thermo-mechanical properties. Specifically, TEMPO modification resulted in an increase in the maximum in-plane contraction ratio, shifting it from −0.40% to −0.59%, along with its corresponding temperature. This research underscores the potential of modified fibers to enhance paper properties and contribute to the development of more sustainable paper-based products.

Cationic modification of cellulose as a sustainable and recyclable adsorbent for anionic dyes

There is a dire need to find an efficient, cost-effective, sustainable, and environment-friendly adsorbent for the removal of anionic pollutants such as dyes from waste effluent. In this work, a cellulose-based cationic adsorbent was designed and utilized for methyl orange and reactive black 5 anionic dyes adsorption from an aqueous medium. Solid-state nuclear magnetic resonance spectroscopy (NMR) revealed the successful modification of cellulose fibers, and dynamic light scattering (DLS) evaluations showed the levels of charge densities. Furthermore, various models for adsorption equilibrium isotherm were utilized to understand the adsorbent characteristics, with the Freundlich isotherm model providing an excellent fit for the experimental results. The modelled maximum adsorption capacity was as much as 1010 mg/g for both model dyes. The dye adsorption was also confirmed using EDX. It was noted that the dyes were chemically adsorbed through the ionic interaction that can be reversed using sodium chloride solution. Overall, the cationized cellulose is inexpensive, environment-friendly, nature-driven, and recyclable making it an appealing adsorbent feasible for the dye removal from textile wastewater effluent.

Extraction and surface modification of cellulose fibers and its reinforcement in starch-based film for packaging composites

BackgroundCellulose extraction from gloss art paper (GAP) waste is a recycling strategy for the abundance of gloss art paper waste. Here, a study was conducted on the impact of ultrasonic homogenization for cellulose extraction from GAP waste to improve the particle size, crystallinity, and thermal stability.ResultsAt treatment temperature of 75.8 °C, ultrasonic power level of 70.3% and 1.4 h duration, cellulose with properties of 516.4 nm particle size, 71.5% crystallinity, and thermal stability of 355.2 °C were extracted. Surface modification of cellulose GAP waste with H3PO4 hydrolysis and 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) oxidation was done followed by starch reinforcement. Surface hydrophobicity and mechanical strength were increased for H3PO4 hydrolysis and TEMPO oxidation starch–cellulose. No reduction of thermal properties observed during the treatment, while increment of crystallinity index up to 47.65–59.6% was shown. Neat starch film was more transparent, followed by starch–TEMPO film and starch–H3PO4 film, due to better homogeneity.ConclusionsThe cellulose GAP reinforced starch film shows potential in developing packaging materials and simultaneously provide an alternative solution of GAP waste recycling.Graphical

Grafting of poly(stearyl acrylate) on cellulose fibers as 3D-printable HDPE composites

This paper aimed to produce a bio-based filament, suitable for 3D printing (fused deposition modeling), made of surface modified cellulose fiber and high density polyethylene. The cellulose fibers (CF) were first surface modified and transformed into a CF-based macroinitiator through an esterification reaction with the 2-bromoisobutyric acid. We finally studied the ability of this CF-based macroinitiator to initiate a single electron transfer-living radical polymerization (SET-LRP) with an hydrophobic monomer: the stearyl acrylate. The grafting of poly(stearly acrylate) onto the cellulose fibers did strongly increased the adhesion, compatibility of the modified fibers with the hydrophobic host matrix (HDPE). Finally, the resulting hydrophobic fibers were extruded with the high density polyethylene (HDPE) through a counter-rotating twin-screw extruder, yielding a bio-based filament suitable for FDM 3d printing. The successful surface modification, such as the correct incorporation of the modified fibers into the thermoplastic matrix, were characterized through ATR-FTIR, 13C CP-MAS NMR, FE-SEM, and mechanical testing. Throughout those characterization techniques, it was concluded that the fiber surface modification significantly improved the compatibility of the fibers with HDPE. Finally, the 3D printing properties of the composite were tested and compared to those of pure HDPE through the 3d printing of simple objects. It was concluded that the printability of the composite made with poly(stearyl acrylate)-grafted cellulose overcomes the problem (shrinkage, warpage, print fidelity) encountered with the printing of pure HDPE.Graphical abstract

Melt processable cellulose fibres engineered for replacing oil-based thermoplastics

If cellulosic materials are to replace materials derived from non-renewable resources, it is necessary to overcome intrinsic limitations such as fragility, permeability to gases, susceptibility to water vapour and poor three-dimensional shaping. Novel properties or the enhancement of existing properties are required to expand the applications of cellulosic materials and will create new market opportunities. Here we have overcome the well-known restrictions that impede melt-processing of high cellulose content composites. Cellulose fibres, partially derivatised to dialcohol cellulose, have been used to manufacture three-dimensional high-density materials by conventional melt processing techniques, with or without the addition of a thermoplastic polymer. This work demonstrates the use of melt processable chemically modified cellulose fibres in the preparation of a new generation of highly sustainable materials with tuneable properties that can be tailored for specific applications requiring complex three-dimensional parts.

PEO/cellulose composite paper based triboelectric nanogenerator and its application in human-health detection

Recently, cellulose paper based triboelectric nanogenerators (CPTENGs) has gained widely attention due to the development of wearable, green and miniaturized electronic products. Modification of cellulose fibers or paper is a feasible method to improve the output performance of CPTENGs, however, the simple and effective routes to improve the triboelectric property of cellulose paper still remain a challenge. Herein, we report a simple method to prepare PEO/cellulose composite paper (PEO/CCP) via mixing polyethylene oxide (PEO) with cationic cellulose fibers. Benefiting from amino groups and PEO, the composite paper exhibits higher triboelectric positive property and triboelectric charge density, thereby endowing PEO/CCP based TENG with outstanding output performance. The voltage, current and power density peak values of PEO/CCP based TENG exhibited linear relationship with amino groups content; in this instance, the performance of the TENGs can be readily adjusted by the amino groups. The voltage, current and power density of PEO/CCP based TENG can be up to 222.1 V, 4.3 μA, and 217.3 mW•m−2, respectively. Moreover, a human-health detection device based on this TENG can monitor the physiological signals such as eye muscles, respiration, heart beat and wrist pulse, promising potentials for applications in human health-care.

Amino modified cellulose fibers loaded zinc oxide nanoparticles via paper-making wet-forming for antibacterial materials

Bacterial infection has become one of the major threats to human health all over the world, and the development and application of antibacterial materials has drawn great attention. Based on the Schiff-base structure, ZnONPs@ACFs are obtained by loading zinc oxide nanoparticles (ZnONPs) on amino cellulose fibers (ACFs) in-situ through the coordination of amino groups with metal ions. The results of FT-IR, XRD and UV-vis demonstrate that ZnONPs are successfully loaded and uniformly dispersed on ACF surface, and the ACFs maintain intact morphology observed by SEM. Furthermore, the zero-span tensile strength of ZnONPs@ACFs is 66.48 N/cm (ROL: 24.98 N/cm/s) under the optimum conditions, which indicates that ZnONPs@ACFs have a certain strength and can be used to make antibacterial sheet materials via paper-making wet-forming process. Accordingly, the ZnONPs@ACF composites show inhibition zones of 4.95 mm and 1.10 mm against E. coli and S. aureus, respectively. The new cellulose-based antibacterial materials demonstrate potential applications in the field of food packaging and biological medicine etc.

Removal of Microcystis aeruginosa and microcystin-LR using chitosan (CTS)-modified cellulose fibers and ferric chloride

The occurrences of harmful algae blooms (HABs) and cyanotoxins such as microcystin-LR (MC-LR) are increasing in water reservoirs and compromise drinking water security. In this study, chitosan (CTS) modified cellulose fibers (CF) were developed as a green adsorbent for the simultaneous removal of a model algae cell, Microcystis aeruginosa, and MC-LR. The results showed that the CTS modification could render amine groups (−NH2) on CF and increased the adsorption affinity toward algae. In the absence of algogenic organic matter (AOM), the algae removal reached 100% at a dosage of 26.7 g-NH2-CF/g-algae (dry weight); however, at the same CF dosage, the presence of AOM (8.13 mg‑carbon·L−1) strongly reduced the adsorption by NH2-CF and removal rate of algae cells reached only 3.2 ± 3.0%. When adding FeCl3 or Fe3+ at a concentration of 11.2 mg-Fe·L−1, the inhibitory effect of AOM was dramatically reduced as indicated by the improved algae removal up to 95% at an NH2-CF dosage of 20.45 g·g−1, because of the reduced energy barrier between NH2-CF and cells. Moreover, when the Fe3+ concentration was increased to 16.8 mg·L−1, 79% of MC-LR was simultaneously removed. Thus, combining Fe3+ with NH2-CF is proven effective to enhance the adsorption and removal of Microcystis aeruginosa and MC-LR and achieve a sustainable mitigation of HABs.

3D printable composites of modified cellulose fibers and conductive polymers and their use in wearable electronics

There are many bioelectronic applications where the additive manufacturing of conductive polymers may be of use. This method is cheap, versatile and allows fine control over the design of wearable electronic devices. Nanocellulose has been widely used as a rheology modifier in bio-based inks that are used to print electrical components and devices. However, the preparation of nanocellulose is energy and time consuming. In this work an easy-to-prepare, 3D-printable, conductive bio-ink; based on modified cellulose fibers and poly(3,4-ethylene dioxythiophene) poly(styrene sulfonate) (PEDOT:PSS), is presented. The ink shows excellent printability, the printed samples are wet stable and show excellent electrical and electrochemical performance. The printed structures have a conductivity of 30 S/cm, high tensile strains (>40%), and specific capacitances of 211 F/g; even though the PEDOT:PSS only accounts for 40 wt% of the total ink composition. Scanning electron microscopy (SEM), wide-angle X-ray scattering (WAXS), and Raman spectroscopy data show that the modified cellulose fibers induce conformational changes and phase separation in PEDOT:PSS. It is also demonstrated that wearable supercapacitors and biopotential-monitoring devices can be prepared using this ink.

Reduced Graphene Oxide‐Gold Nanoparticle Nanohybrid Modified Cost‐Effective Paper‐Based Biosensor for Procalcitonin Detection

AbstractThe present study reports the fabrication of reduced graphene oxide (rGO)/gold nanoparticles (AuNP) nanocomposites modified cellulose fiber paper‐based electrochemical biosensor for procalcitonin (PCT) biomarker detection. PCT is a biomarker specific for bacterial infection (BI) detection and has gained much attention as a potential solution to the problems associated with determining appropriate antibiotic use. In sepsis and other severe infections, serum PCT levels increase to values above 100 ng mL−1 in response to pro‐inflammatory stimulation. The structural and morphological characterization of the rGO‐AuNP composite are investigated using UV‐Vis spectroscopy, FTIR spectroscopy, X‐ray diffraction, and scanning electron microscopy. Monoclonal antibodies specific to PCT were covalently immobilized onto the rGO‐AuNP nanocomposite modified paper to fabricate an electrochemical biosensor. The fabricated biosensor exhibits linearity in the PCT concentration range 10 −15×103 pg mL−1, with a low detection limit 10 pg mL−1. Furthermore, the proposed biosensor also exhibited good selectivity and could detect PCT biomarkers even in the presence of other interfering electroactive species such as glucose, oxalic acid, and urea. The proposed CF‐based biosensor has been proven as an accelerated simple point‐of‐care (POC) exploratory approach for early PCT diagnosis in inadequate areas with limited production facilities, computational techniques, and highly skilled experts.