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Creators/Authors contains: "Ujjain, Sanjeev Kumar"

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  1. The adoption of single-use plastics for fabricating lab-on-chip devices used in sensors, chemical and biomedical processes is escalating into a major environmental issue. To address the global need for developing long-term sustainable solutions, we present wood microfluidics as an alternative for electrochemical sensing. The lab-on- wood-chip (LOWC) device developed in this study demonstrated (i) versatility in electrochemical applications (electropolymerization and corrosion analysis), (ii) stability under highly acidic (pH 0.5), basic (pH 14.0) and varied temperature (4◦–60 ◦C) conditions (iii) long-term consistency in performance (>12 months), and (iv) potential for on-field nitrate sensing towards environmental monitoring – in a cost-effective, simple and sustainable manner. 
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    Free, publicly-accessible full text available October 1, 2026
  2. Free, publicly-accessible full text available May 12, 2026
  3. null (Ed.)
    Abstract Isotopes of heavier gases including carbon ( 13 C/ 14 C), nitrogen ( 13 N), and oxygen ( 18 O) are highly important because they can be substituted for naturally occurring atoms without significantly perturbing the biochemical properties of the radiolabelled parent molecules. These labelled molecules are employed in clinical radiopharmaceuticals, in studies of brain disease and as imaging probes for advanced medical imaging techniques such as positron-emission tomography (PET). Established distillation-based isotope gas separation methods have a separation factor ( S ) below 1.05 and incur very high operating costs due to high energy consumption and long processing times, highlighting the need for new separation technologies. Here, we show a rapid and highly selective adsorption-based separation of 18 O 2 from 16 O 2 with S above 60 using nanoporous adsorbents operating near the boiling point of methane (112 K), which is accessible through cryogenic liquefied-natural-gas technology. A collective-nuclear-quantum effect difference between the ordered 18 O 2 and 16 O 2 molecular assemblies confined in subnanometer pores can explain the observed equilibrium separation and is applicable to other isotopic gases. 
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