https://scholar.korea.ac.kr/handle/2021.sw.korea/2473 Fri, 10 Apr 2026 12:28:26 GMT 2026-04-10T12:28:26Z https://scholar.korea.ac.kr/handle/2021.sw.korea/269427 Title: On-site microfluidic aptasensor for rapid and highly selective detection of microcystin-LR Authors: Lee, Jihye; Oh, Byeolnim; Park, Jaewon; Kim, Jee Young; Son, Jino; Kim, Hyun Soo; Choi, Yoon-E Abstract: To detect microcystin-LR (MC-LR), a potent cyanotoxin harmful to human health, fast and precise monitoring tools are essential, particularly for on-site applications. In this study, we developed a novel on-site microfluidic aptasensor system that utilizes a fluorescence-tagged aptamer for the rapid and selective detection of MC-LR. By employing a target non-immobilized aptamer selection technique, high-affinity DNA aptamers for MC-LR were identified, and then further optimized through sequence truncation to enhance detection efficiency. The developed aptamer was designed such that its fluorescence is quenched in the absence of MC-LR, but recovered in its presence, enabling a clear signal detection that correlates with a toxin concentration. The developed system achieved a detection limit of 1.9 ppb, significantly lower than the safety threshold suggested by world health organization (WHO) for recreational waters, demonstrating sufficient sensitivity for reliable on-site monitoring. In addition, the microfluidic aptasensor system demonstrated high specificity, exhibiting the strongest response to MC-LR compared to other cyanotoxins. This system is the first portable MC-LR detection tool that allows for on-site environmental monitoring with the advantages of its fast response time and ease of operation. Combining a low detection limit with high accuracy, the microfluidic aptasensor system presents a promising alternative to conventional laboratory-based methods, providing a practical and reliable solution for water quality assessment. © 2025 Elsevier B.V. Wed, 01 Oct 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/269427 2025-10-01T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/267951 Title: Upcycling of plastic wastes, polyethylene terephthalate (PET) into photocatalyst under visible light: Application for dye removal Authors: Izzati binti Tan Yusop, Nur Amirah; Na, Joorim; Pandi, Kalimuthu; Nam, Gwiwoong; Jung, Jinho Abstract: Upcycling waste plastics for photocatalyst production can be a promising strategy for management and prevention of plastic waste. This study aims to synthesise iron oxide-modified titania (IMT) nanocomposite photocatalysts using waste plastic, polyethylene terephthalate, and to evaluate their effectiveness in dye removal. The IMT photocatalysts were synthesised by loading iron-MOFs (Fe-MOFs) onto TiO2, resulting in an octahedral crystal structure shaped by both Fe and TiO2. Hydroxyl radical production of IMT photocatalyst was demonstrated superior efficiency compared to the standard visible light photocatalyst, g-C3N4. Moreover, the removal efficiency of organic dyes such as cationic and anionic dyes (Methylene Blue, Rhodamine B, Eosin Y and Bromophenol Blue) by the photocatalysts successfully achieved as 90 % removal for both Eosin Y and Bromophenol Blue meanwhile 75 % removal for Rhodamine B, and 60 % removal for Methylene Blue. Cationic dyes revealed particularly high removal efficiencies. The synthesised IMT photocatalyst offers a cost-effective solution for removing organic dyes and contributes to global efforts in managing plastic waste and mitigating environmental pollution. © 2025 The Korean Society of Industrial and Engineering Chemistry Mon, 25 Aug 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/267951 2025-08-25T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/269363 Title: Effect of drying treatment on the leachability of metallic elements (Zn, As, Cd, and Pb) from amended mine soils during batch leaching experiments Authors: Kim, Juhee; Lim, Heyyeon; Jang, Yoojin; Park, Minseok; Moon, Deok Hyun; Lee, Goontaek; Hyun, Seunghun Abstract: Chemical amendments are frequently applied to immobilize toxic elements in contaminated soils. However, remobilization of elements in amended soils is poorly understood. The elution of metallic elements (Zn, As, Cd, and Pb) from mine soil amended with mine sludge (MS), steel slag (SS), and limestone (LS) was evaluated using batch leaching tests under continuous wetting and intermittent drying. The elements were effectively immobilized by the three amendments, as evidenced by the reductions in the labile fraction (10.6-78.8 %) of SEP (sequential extraction procedure) and cumulative mass (42.0-98.5 %) during 14 leaching runs. Drying events increased the leaching potential by 2.9-fold and 4.4-fold for the eluted mass (mu g) and depletion rate (k, h(-1)), respectively. The depletion rate of cationic elements (e.g., Zn, Cd, and Pb) from the amended samples (MSS, SSS, and LSS) correlated with the leachate pH (r(2) > 0.583), while the leaching of anionic element (e.g., As) from MSS and SSS correlated well with the leachate concentration of Fe (r(2) = 0.898). The findings indicate that drying events can substantially increase the remobilization of metallic elements from amended soils. Moreover, change in the leachate phase, such as the pH drop (up to 1.5 unit) and/or the Fe concentration rise (up to 62 %), can be an early sign of the increased remobilization potential of metallic elements in amendment-treated remediation sites. Sun, 01 Jun 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/269363 2025-06-01T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/271408 Title: A green infrastructure planning approach for enhanced flood control and resilience in urban areas Authors: Rahman, Rakesur; Kang, Sujeong; Lee, Sangchul; Lee, Junga Abstract: Urban flooding presents a growing challenge in metropolitan areas due to climate change and increasing impervious surfaces. This research proposes a Green Infrastructure (GI) planning approach to enhance flood control and resilience in the flood-prone Yeoksam-dong region of Gangnam, Seoul, South Korea. A mixed-method approach was employed, incorporating both residents' preferences and hydrological simulations using the Stormwater Management Model (SWMM) to assess the effectiveness of various GI controls. Key GI co-benefits were identified through importance-performance analysis (IPA) and fuzzy weight rankings. Based on these, three GI scenarios were developed and evaluated for their flood mitigation potential. Scenario 1 (infiltration trench, rain garden, and rain barrel) emerged as the most effective, reducing surface runoff by 18.56 % and achieving the best cost-benefit ratio of 1.01 over a 10-year period. Scenario 2 (bio-retention, pervious pavement, and green roof), while less effective in terms of flood mitigation, may still offer ecological and social co-benefits. The study also conducted a sensitivity analysis, which confirmed Scenario 1's robustness across various levels of imperviousness, making it a highly adaptable solution for urban settings. This research highlights the importance of community engagement in GI planning and demonstrates how integrating hydrological performance with socioeconomic benefits can enhance urban resilience. By aligning with the 4Rs of resilience; robustness, redundancy, resourcefulness, and rapidity, this study provides actionable insights for policymakers and urban planners seeking cost-effective, scalable solutions for flood-prone areas. The findings underscore the value of multifunctional GI controls in not only reducing flood risks but also promoting long-term sustainability and community well-being. Sun, 01 Jun 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/271408 2025-06-01T00:00:00Z