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Paper mills inevitably produce various pollutants, including chlorolignin, chlorophenols, chloroguaiacol, furan, cyanide, and heavy metals. These pollutants cause significant threats to aquatic and terrestrial life. The pulp and paper industries are looking for eco-friendly solutions for the disposal of effluents during paper processing. Moreover, environmental management practices are a key concern that may be addressed by removing these effluents using suitable bioremediation techniques. Therefore, we have discussed several eco-friendly nanotechnology based sustainable bioremediation technologies like the use of nanoparticles, nanomaterials, nanocomposites, nanoadsorbents, and several advanced methods such as electrocoagulation and photocatalysis, which may be utilized for the elimination of hazardous pollutants from paper industry effluents. This review finally includes critical insight into the potential use of the above-mentioned nanotechnology based interventions for mitigation of contaminants from the paper industry. Nevertheless, there are a few limitations and challenges toward implementation of such technologies, which are also discussed in this review., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Membraneless microfluidic fuel cells (MFCs) have garnered tremendous interest as micropower devices, which exploit the colaminar nature of two aqueous electrolytes to separate the anode and cathode and avoid the membrane usually used in a fuel cell. Our previous research shows that the performance of FeCl3-based MFCs with catalyst-free cathodes is mainly limited by the cathode. To improve the power output of these MFCs, we activated the carbon paper cathode by an electrochemical method in the three solutions (Na2SO4, NaOH, and H2SO4) to improve the electrochemical characteristics of the carbon paper cathode. The surface functionalities and defects, reduction activation of iron ions as the oxidant, cathode resistance, and performance of FeCl3-based MFCs were measured and compared. Our work shows that the electrochemical activation of the carbon paper in different solutions is a simple and effective method to enhance the electrochemical characteristics of the carbon paper cathode and improve the performance of the FeCl3-based MFC. Also, the MFC with the carbon paper cathode activated in the H2SO4 solution reaches the optimum performance: 235.6 mW cm-3 in volumetric power density and 1063.33 mA cm-3 in volumetric limiting current density, which are 1.58 and 1.52 times as much as that of a MFC with an untreated carbon paper cathode, respectively. This best performance can be attributed to the cathode activated in the H2SO4 solution with the largest number of oxygen-containing functional groups, the largest electrochemical active surface area, strongest reduction of iron ions, and least resistance of the cathode.

Candida albicans ( C. albicans ) infections pose significant challenges in clinical settings due to their high morbidity and mortality rates in addition to their role in tumor progression. Current diagnostic methods, while effective, often suffer from limitations that hinder a timely intervention. Therefore, there is an urgent need for a simple, sensitive, specific, and low-cost colorimetric biosensor for the rapid detection of C. albicans . This new biosensing platform comprises a gold platform carrying a specific C. albicans peptide substrate conjugated with magnetic nanobeads. Hence, the sensing platform was black, and the operation was based on the proteolytic activity of C. albicans , offering a visual color change to yellow upon cleavage of the conjugated peptide substrates on the magnetic nanobeads. Specificity testing demonstrated the biosensor's ability to distinguish C. albicans from other Candida species and microorganisms, while stability testing confirmed its long-term performance. Clinical testing revealed the biosensor's high sensitivity in detecting C. albicans in both standard cultures and clinically isolated samples with a lower limit of detestation of 3.5 × 10 3 CFU/mL. Although further validation against conventional and molecular methods is warranted, our colorimetric biosensor holds promise as a rapid (5 min) and cheap (Less than 2 $) point-of-care solution for the early detection of C. albicans infections, facilitating a timely intervention and improving patient outcomes in clinical practice., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The proposed integrated experimental and simulation study focuses on the mechanical behavior and failure analysis of coupled paper-aluminum (paper-Al) laminates for sustainable packaging. The research employs an innovative experimental approach combining uniaxial loading with in situ visualization of sample deformation. The acquired experimental data are utilized to validate a simulation model, ensuring its accuracy and reliability. Parametric studies conducted through the finite element model further enhance our understanding of the mechanical behavior of the coupled laminates. Specifically, the study investigates microscopic mechanisms influencing the overall response of laminates in both the machine direction (MD) and the cross-machine direction (CD), presenting a comparative analysis with traditional aluminum-polyethylene (Al-PE) laminates, which is a prevalent choice in the packaging industry. The findings contribute to a better comprehension of key factors affecting the mechanical behavior of paper-Al laminates, enabling the design of more effective and sustainable solutions for the packaging industry. Results indicate the advantage of increasing the laminate thickness in the MD, demonstrating an enhanced strength. Conversely, the sensitivity of the thickness variation in the CD is found to be less pronounced. Additionally, our investigation highlights the substantial potential of paper-based materials as environmentally friendly alternatives, particularly in contrast to Al-PE laminates. Furthermore, integrating an innovative digital twin model, which combines experimental data and simulation, significantly advances our understanding and application of laminated in the context of paper packaging design., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Paper lateral flow immunoassays combined with surface-enhanced Raman scattering (SERS) technology have gained increasing attention due to their high sensitivity characteristics resulting from the amplified SERS signals of the plasmon-enhanced optical probes. In contrast to conventional colorimetric lateral flow strips, SERS paper lateral flow strips (SERS-PLFSs) are currently not commercially available for widespread use. Analytical validation is the key step for commercialization. In this work, we have developed a PLFS with a hierarchical SERS probe (gold-silver nanoparticle@Raman reporter@silica) for detection of the US Food and Drug Administration (FDA)-approved traumatic brain injury (TBI) protein biomarker, ubiquitin C-terminal hydrolase-L1 (UCH-L1), in blood plasma samples. Analytical validation has been performed on this SERS-PLFS in terms of the limit of detection (LOD), limit of quantification (LOQ), accuracy, precision, selectivity, and stability. The SERS-PLFS exhibits a reportable range of 0.2-100 ng/mL with a LOD of 0.08 ng/mL toward measurement of UCH-L1 in blood plasma. The SERS-PLFS has been applied to clinical TBI samples. The test results were compared with those from enzyme-linked immunosorbent assay (ELISA), demonstrating a strong correlation between the two analytical methods. This study has important implications in the commercialization of SERS-PLFSs for rapid TBI detection in clinical practice., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The urgent need for sustainable and efficient energy conversion technologies has propelled research into novel electrocatalysts for fuel cell applications. This study investigates a carbon paper (CP)-supported Ni 2 O 3 catalyst for the electrocatalytic oxidation of ethanol. We utilized electrodeposition to uniformly deposit/dop Ni 2 O 3 onto the CP, creating an effective electrocatalyst. Our approach allows the tailoring of the doping degree by adjusting the electrodeposition potential. The optimal doping degree, achieved at a medium deposition potential, results in an electrode with high intrinsic activity and a substantial electrochemically active surface area (ECSA), thereby enhancing its electrocatalytic activity. This catalyst efficiently facilitates the oxidation of ethanol to formic acid while maintaining good stability. The enhanced performance is attributed to the effective interface and interaction between Ni 2 O 3 and CP. This work not only provides insights into the design of efficient Ni-based catalysts for ethanol oxidation but also paves the way for developing advanced materials for renewable energy conversion., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Glucose oxidase (GOx) activity assays are vital for various applications, including glucose metabolism estimation and fungal testing. However, conventional methods involve time-consuming and complex procedures. In this study, we present a colorimetric platform for in situ GOx activity measurement utilizing redox-sensitive electrochromic nanoparticles based on polyaniline (PAni). The glucose-adsorbed colorimetric paper sensor, herein termed Glu@CPS, is created by immobilizing ferrocene and glucose onto paper substrates that have been functionalized with PAni nanoparticles. Glu@CPS not only demonstrated rapid detection (within 5 min) but also exhibited remarkable selectivity for GOx and a limit of detection as low as 1.25 μM. Moreover, Glu@CPS demonstrated consistent accuracy in the measurement of GOx activity, exhibiting no deviations even after being stored at ambient temperature for a duration of one month. To further corroborate the effectiveness of this method, we applied Glu@CPS in the detection of GOx activity in a moldy red wine. The results highlight the promising potential of Glu@CPS as a convenient and precise platform for GOx activity measurement in diverse applications including food quality control, environmental monitoring, and early detection of fungal contamination., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Here, we introduce an environmentally friendly approach to fabricate a simple and cost-effective plasmonic paper for detecting food additives using surface-enhanced Raman spectroscopy (SERS). The plasmonic paper is fabricated by in situ growth of gold nanoparticles (AuNPs) on filter paper (FP). To facilitate this green fabrication process, we applied a double-layered coating of biopolymers, chitosan (CS) and alginate (ALG), onto the FP using a layer-by-layer (LbL) assembly through electrostatic interactions. Compared to single-layer biopolymer coatings, double-layered biopolymer-coated paper, ALG/CS/FP, significantly improves the reduction properties. Consequently, effective in situ growth of AuNPs can be achieved as seen in high density of AuNP formation on the substrate. The resulting plasmonic paper provides high SERS performance with an enhancement factor (EF) of 5.7 × 10 10 and a low limit of detection (LOD) as low as 1.37 × 10 -12 M 4-mercaptobenzoic acid (4-MBA). Furthermore, it exhibits spot-to-spot reproducibility with a relative standard deviation (RSD) of 8.2% for SERS analysis and long-term stability over 50 days. This paper-based SERS substrate is applied for melamine (MEL) detection with a low detection limit of 0.2 ppb, which is sufficient for monitoring MEL contamination in milk based on food regulations. Additionally, we demonstrate a simultaneous detection of β-agonists, including ractopamine (RAC) and salbutamol (SAL), exhibiting the multiplexing capability and versatility of the plasmonic paper in food contaminant analysis. The development of this simple plasmonic paper through the LbL biopolymer assembly not only paves the way for novel SERS substrate fabrication but also broadens the application of SERS technology in food contaminant monitoring., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Chemical tracers are indispensable tools for enhancing reservoir characterization and optimizing production processes in the oil and gas industry. Particularly, interwell water tracers provide key data for efficient water flood management and the improvement of production rates. However, the analysis of these water tracers within reservoir fluids is challenging, requiring laborious separation and extraction steps that often rely on complex instruments and skilled operators. Real-time analysis is especially problematic in remote areas with limited access to well-equipped laboratories. To address these challenges, we introduce a paper-based platform for the time-resolved fluorescence detection of dipicolinic acid (DPA) tracers complexed with terbium ion (Tb 3+ ). Our innovation is driven by the need to simplify tracer analysis, make it portable, and enhance accessibility for oilfield applications. By leveraging the unique properties of cyclen-based macrocyclic ligands, we have achieved the stable and sensitive immobilization of Tb 3+ on quartz microfilter paper, eliminating the need for extensive laboratory-based procedures. We achieve the stable and sensitive immobilization of Tb 3+ on quartz microfilter paper by leveraging the unique properties of cyclen-based macrocyclic ligands. This innovation enables the formation of highly fluorescent, oil-blind, and optically detectable DPA-Tb 3+ complexes at the paper surface. We visualize and capture these fluorescence signals using an intensified charge-coupled device camera via time gating, effectively suppressing undesirable fluorescence originating from crude oil. The quantification of DPA concentrations is achievable down to 158 ppb (9.45 × 10 -7 M), as confirmed through time-resolved fluorescence microplate reader measurements. We also demonstrate the practicality of our technology by detecting DPA tracers in the presence of crude oil contamination, a common challenge encountered in oil production wells., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)