Zhuolun Meng, Liam White, Pengfei Xie, Hassan Raji, S Reza Mahmoodi, Aris Karapiperis, Hao Lin, German Drazer, Mehdi Javanmard, Edward P DeMauro
{"title":"A label-free nanowell-based impedance sensor for ten-minute SARS-CoV-2 detection.","authors":"Zhuolun Meng, Liam White, Pengfei Xie, Hassan Raji, S Reza Mahmoodi, Aris Karapiperis, Hao Lin, German Drazer, Mehdi Javanmard, Edward P DeMauro","doi":"10.1039/d5sd00002e","DOIUrl":"https://doi.org/10.1039/d5sd00002e","url":null,"abstract":"<p><p>This work explores label-free biosensing as an effective method for biomolecular analysis, ensuring the preservation of native conformation and biological activity. The focus is on a novel electronic biosensing platform utilizing micro-fabricated nanowell-based impedance sensors, offering rapid, point-of-care diagnosis for SARS-CoV-2 (COVID-19) detection. The nanowell sensor, constructed on a silica substrate through a series of microfabrication processes including deposition, patterning, and etching, features a 5 × 5 well array functionalized with antibodies. Real-time impedance changes within the nanowell array enable diagnostic results within ten minutes using small sample volumes (<5 μL). The research includes assays for SARS-CoV-2 spike proteins in phosphate-buffered saline (PBS) and artificial saliva buffers to mimic real human SARS-CoV-2 samples, covering a wide range of concentrations. The sensor exhibits a detection limit of 0.2 ng mL<sup>-1</sup> (1.5 pM) for spike proteins. Middle East respiratory syndrome (MERS-CoV) spike proteins are differentiated from SARS-CoV-2 spike proteins, demonstrating specificity.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12056702/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144031478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maede Chabi, Binh Vu, Kristen Brosamer, Sophia Song, Vijay Maranholkar, Zihua Zeng, Youli Zu, Rashmi Kanagal-Shamanna, Jacinta C. Conrad, Richard C. Willson and Katerina Kourentzi
{"title":"Lateral flow assay-based detection of nuclear fusion oncoprotein: implications for screening of acute promyelocytic leukemia†","authors":"Maede Chabi, Binh Vu, Kristen Brosamer, Sophia Song, Vijay Maranholkar, Zihua Zeng, Youli Zu, Rashmi Kanagal-Shamanna, Jacinta C. Conrad, Richard C. Willson and Katerina Kourentzi","doi":"10.1039/D4SD00357H","DOIUrl":"10.1039/D4SD00357H","url":null,"abstract":"<p >Due to the slow progression of most cancers, speed of diagnosis is not of primary concern. However, the diagnosis of acute promyelocytic leukemia (APL) is unusually urgent because its hemorrhagic complications can result in death within a few days. APL is highly treatable, but the turnaround time for standard molecular testing often exceeds the window for life-saving treatment, even in advanced medical centers. The hallmark of APL is the fusion of the PML and RARα genes (t(15;17)) resulting in the expression of a growth-promoting PML–RARα fusion protein. Toward timely screening for APL, we have developed a sensitive europium-based lateral flow immunoassay for direct detection of nuclear PML–RARα fusion oncoprotein. We demonstrated a limit of detection of 11% fusion protein positive NB4 cells spiked into healthy peripheral blood mononuclear cells and an integrated filter-based sample preparation workflow showcasing its potential for clinically actionable utility in prompt APL screening. With further validation with clinical human samples this lateral flow immunoassay has the potential to enable fusion-protein based cancer diagnostics at true point-of-care.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 5","pages":" 416-424"},"PeriodicalIF":3.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11938210/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143756311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mizuki Tomizawa, Kiwako Watanabe, Kaori Tsukakoshi and Kazunori Ikebukuro
{"title":"Detection of CpG methylation based on the change in amplification efficiency of strand-displacement DNA polymerase by CpG methylation†","authors":"Mizuki Tomizawa, Kiwako Watanabe, Kaori Tsukakoshi and Kazunori Ikebukuro","doi":"10.1039/D5SD00012B","DOIUrl":"https://doi.org/10.1039/D5SD00012B","url":null,"abstract":"<p >A method for detecting CpG methylation is required in clinical settings because CpG methylation is associated with various diseases. CpG methylation leads to structural changes in single-stranded DNA and also changes the stability of double-stranded DNA. We hypothesized that the amplification efficiency of DNA polymerase, with its strand displacement ability, might be altered by CpG methylation. We chose loop-mediated isothermal amplification (LAMP), which uses strand displacement DNA synthesis, for its validation. The LAMP products from the synthetic DNA of the upstream region of the dopamine receptor D2 (<em>DRD2</em>) and the androgen receptor (<em>AR</em>) promoter region were detected by turbidity and fluorescence intensity measurements. The methylated synthetic DNA was amplified more slowly than the unmethylated synthetic DNA. The LAMP products from the human genomic DNA were detected by fluorescence intensity measurement and electrophoresis. The highly methylated genomic DNA was amplified slower than the less methylated genomic DNA in the <em>AR</em> promoter region. CpG methylation detection through differences in the amplification efficiency of LAMP reaction may be used for a rapid and easy detection method of CpG methylation.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 5","pages":" 397-406"},"PeriodicalIF":3.5,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d5sd00012b?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144073549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Supreeth Setty, Heeyeong Jang, Jungyoup Han, Joo Youn Park, Nogi Park, Keun Seok Seo and Chong Ahn
{"title":"A new sequential dual flow lab-on-a-chip with a lyophilized one-component chemiluminescence substrate for high-sensitive microchannel lateral flow assay (mLFA)","authors":"Supreeth Setty, Heeyeong Jang, Jungyoup Han, Joo Youn Park, Nogi Park, Keun Seok Seo and Chong Ahn","doi":"10.1039/D4SD00352G","DOIUrl":"https://doi.org/10.1039/D4SD00352G","url":null,"abstract":"<p >Recently, there has been a growing demand for the development of lab-on-a-chip (LOC) platforms with new assays and detection protocols for point-of-care-test (POCT) applications. So far, chemiluminescence (CL) detection-based immunoassays have shown promising performance for the high-sensitive POCT, but they require automated machines or multiple manual steps to perform the CL-based assay. In this work, a fully automated CL-based immunoassay was developed using a new sequential dual flow LOC with on-chip lyophilized CL substrate, and then a highly specific and sensitive immunoassay using a pair of single chain variable fragment (scFv) capture and detection antibodies was successfully performed. The concept of sequential and automatic control of dual flows, which was strongly desired for ensuring that the reconstituted detection antibody conjugated with horseradish peroxidase flowed first through the reaction zones and then the reconstituted CL substrate flowed, was newly developed and implemented on the LOC. In addition, a new one-component CL substrate in liquid format was introduced and lyophilized for the on-chip lyophilized substrate, developing a new lyophilization process. To evaluate the assay performance on the developed new LOC platform, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was chosen as a demonstration vehicle. The nucleocapsid (N) protein of SARS-CoV-2 was analyzed using the custom-developed scFv antibody pair from a phage display library system, which showed a better limit of detection (LoD) over the commercially available rapid diagnostic test (RDT) kits for detecting SARS-CoV-2. Finally, a portable reader for reading the CL signal from the CL-based microchannel lateral flow assay (CL-mLFA) was developed and used for evaluating the performance of the SARS-CoV-2 assay on the developed LOC platform. An LoD of approximately 1.6 ng mL<small><sup>−1</sup></small> was achieved, which was acceptable for the early diagnosis of SARS-CoV-2 infection. The new CL-mLFA platform developed in this work, adopting the sequential dual flow LOC and the lyophilized one-component CL substrate, can be applied to other high-sensitive immunoassays in POCT for diagnosing various chronic or infectious diseases.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 4","pages":" 320-335"},"PeriodicalIF":3.5,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d4sd00352g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kevin Alexander Janus, Madita Zach, Stefan Achtsnicht, Aleksander Drinic, Alexander Kopp, Michael Keusgen and Michael Josef Schöning
{"title":"Modification of a bioabsorbable carbon electrode on silk-fibroin carriers: setting the composition and adjustment of the working potential†","authors":"Kevin Alexander Janus, Madita Zach, Stefan Achtsnicht, Aleksander Drinic, Alexander Kopp, Michael Keusgen and Michael Josef Schöning","doi":"10.1039/D4SD00371C","DOIUrl":"https://doi.org/10.1039/D4SD00371C","url":null,"abstract":"<p >In this work, different surface treatment and modification procedures (KCl, Na<small><sub>2</sub></small>CO<small><sub>3</sub></small>, H<small><sub>2</sub></small>O<small><sub>2</sub></small>, O<small><sub>2</sub></small> plasma, multi-walled carbon nanotubes (MWCNTs)) are applied to a screen-printed carbon-based electrode on bioabsorbable silk-fibroin, aiming to reduce the applied working potential in operation. The screen-printed carbon electrode houses the enzyme glucose oxidase for glucose monitoring, and is encapsulated by the biocompatible material Ecoflex. The working electrode is characterized amperometrically at different working potentials (0.6 to 1.2 V <em>vs.</em> the Ag/AgCl reference electrode) at physiological glucose concentrations ranging from 0.5 to 10 mM. The surface morphology of the electrode is analyzed utilizing scanning electron microscopy and contact angle measurements. Addition of 2 wt% MWCNTs to the carbon screen-printing paste allowed the reduction of the applied working potential from 1.2 to 0.8 V, resulting in a mean glucose sensitivity of 2.5 ± 0.6 μA cm<small><sup>−2</sup></small> mM<small><sup>−1</sup></small>. Moreover, the bioabsorbability (<em>i.e.</em>, the degradation behavior) of the different surface-treated carbon electrodes on silk-fibroin is studied over several months using the enzyme protease XIV from <em>Streptomyces griseus</em>.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 4","pages":" 353-362"},"PeriodicalIF":3.5,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d4sd00371c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kawin Khachornsakkul, Darrien Johnsen and Sameer Sonkusale
{"title":"Headspace paper-based analytical device for ammonia quantification in human biological samples","authors":"Kawin Khachornsakkul, Darrien Johnsen and Sameer Sonkusale","doi":"10.1039/D4SD00361F","DOIUrl":"https://doi.org/10.1039/D4SD00361F","url":null,"abstract":"<p >This article presents a simple and cost-effective headspace paper-based analytical device (hPAD) for the quantification of ammonia in human biological samples. The aim of this approach is to enhance the detection selectivity for ammonia in complex samples. The detection principle leverages basic chemistry, wherein ammonia reacts with copper sulfate (CuSO<small><sub>4</sub></small>) to form the complex ion tetraamminecopper(<small>II</small>) sulfate ([Cu(NH<small><sub>3</sub></small>)<small><sub>4</sub></small>]SO<small><sub>4</sub></small>), resulting in a colour change from pale blue to dark blue on a paper substrate. The quantitative analysis of ammonia is straightforward through placement of the sensor on the inside lid of the sample vial, and the resulting colour change is measured using a smartphone and image processing software. Upon optimization, the developed assay demonstrated a linear range between 2.5 and 40.0 μM (<em>R</em><small><sup>2</sup></small> = 0.9955) with a detection limit (LOD) of 0.90 μM. The sensor also exhibited high precision, with the highest relative standard deviation (RSD) recorded at 6.17%. Moreover, the method showed remarkable selectivity, as the sensor showed no response to common interfering molecules in a complex biological matrix. The technique is fast, requiring only 4 min for the reaction, and does not necessitate any heating procedures. Furthermore, the developed method provides excellent accuracy for detecting ammonia levels in both human serum and urine samples, with recovery rates ranging from 93.4% to 107.6%. Therefore, the hPAD offers a simple and affordable solution by sensing in the headspace that overcomes the limitations of direct measurement in the sample, which may be affected by the colour, pH, other existing ions and molecules in the sample solution. Overall, this approach is suitable for various applications in both medical and environmental analysis.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 4","pages":" 345-352"},"PeriodicalIF":3.5,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d4sd00361f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mannanthara Kunhumon Noushija, Alenthwar Vamshi Krishna, Ruhila Taj Mehboob Ali and Sankarasekaran Shanmugaraju
{"title":"Reactivity-based small-molecule fluorescence probes for sensing biogenic amine cadaverine – a biomarker to determine food freshness","authors":"Mannanthara Kunhumon Noushija, Alenthwar Vamshi Krishna, Ruhila Taj Mehboob Ali and Sankarasekaran Shanmugaraju","doi":"10.1039/D4SD00358F","DOIUrl":"https://doi.org/10.1039/D4SD00358F","url":null,"abstract":"<p >The design and fabrication of sensor probes to check food freshness and assess food quality is an essential area of research. Every year, millions of people are affected by food poisoning and fall victim to foodborne-related health problems. Cadaverine (1,5-pentanediamine) is a biogenic amine and an important biomarker to determine food freshness. Measuring cadaverine concentration allows us to assess the quality and freshness of food. Recently, fluorescence-based sensing methods have been used extensively as a viable probe to measure cadaverine concentrations. In this review article, we have summarized reactivity-based small-molecule fluorescence chemosensors reported to date for sensing and quantification of cadaverine. We provide a detailed discussion of the design, synthesis, and fluorescence-sensing properties of several small-molecule sensors employed for cadaverine detection. Lastly, the limitations of existing fluorescence sensors and our view on future perspectives for developing practically useful fluorescence sensor systems for real-time monitoring of the concentrations of cadaverine biomarkers have been stated. Given its importance, this review article will attract and greatly benefit scientists working in related research areas.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 4","pages":" 293-309"},"PeriodicalIF":3.5,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d4sd00358f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Selective sensing of heavy metal ions using carbon dots synthesized from Azadirachta indica seeds†","authors":"Somedutta Maity, Santhosh Kumar, Gurmeet Singh, Sukanya Patra, Divya Pareek and Pradip Paik","doi":"10.1039/D4SD00350K","DOIUrl":"https://doi.org/10.1039/D4SD00350K","url":null,"abstract":"<p >There have been notable advancements in the technology associated with using waste resources to create novel and beneficial products. This study demonstrates that the kernel part of <em>Azadirachta indica</em> (Neem) seeds can be sustainably used for this purpose. Carbon dots (CDs) of approximately <em>ca.</em> 4–8 nm in size were synthesized from the kernel <em>Azadirachta indica</em> seeds through calcination, followed by surface modification using diethylamine, sodium methoxide, and alcohol. This produced waste seed-derived luminous surface-quaternized CDs (Ai-CDs). These CDs were used as a fluorescent nanoprobe to detect inorganic contaminants at concentrations ranging from low (5 μM) to high (120 μM), due to their strong photostability and excitation-dependent emission in aqueous solutions. Ai-CDs were used to measure the levels of Cd<small><sup>+2</sup></small> and As<small><sup>3+</sup></small> in solution through quenching of luminescence intensity (“turn-off”), while cupric ions (Cu<small><sup>+2</sup></small>) selectively increased fluorescence (“turn-on”) for sensing. The current method of synthesising CDs offers quick reaction times, along with great selectivity and sensitivity. The CDs preferentially absorbed Cd<small><sup>2+</sup></small> and As<small><sup>3+</sup></small>, causing a sharp dimming in fluorescence intensity by 27% and 30%, respectively. In contrast, for Cu<small><sup>+2</sup></small> and Cu<small><sup>+</sup></small> the fluorescence intensity was enhanced. Consequently, this unique characteristic was utilized to exclude and identify Al<small><sup>3+</sup></small>, Cd<small><sup>2+</sup></small>, Mn<small><sup>2+</sup></small>, Ni<small><sup>2+</sup></small>, Co<small><sup>2+</sup></small>, Cu<small><sup>2+</sup></small>, and Cu<small><sup>+</sup></small> ions, with detection limits ranging from 5 μM to 120 μM. Furthermore, we demonstrated the heavy metal ion sensing activity of CDs from their salt solutions, highlighting their potential as environmentally friendly metal ion detection agents. A cell viability assay was carried out, revealing that the CDs are non-toxic.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 5","pages":" 407-415"},"PeriodicalIF":3.5,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d4sd00350k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144073550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ishika Ishika, Walid M. Hassen, René St-Onge, Houman Moteshareie, Azam F. Tayabali and Jan J. Dubowski
{"title":"Regenerable photonic aptasensor for detection of bacterial spores with stacks of GaAs–AlGaAs nanoheterostructures†","authors":"Ishika Ishika, Walid M. Hassen, René St-Onge, Houman Moteshareie, Azam F. Tayabali and Jan J. Dubowski","doi":"10.1039/D4SD00367E","DOIUrl":"https://doi.org/10.1039/D4SD00367E","url":null,"abstract":"<p >The reusability of biosensors is a crucial advancement in environmental monitoring and laboratory efficiency. In this study, we introduce the concept of a regenerable aptasensor based on digital photocorrosion (DIP) of a GaAs–AlGaAs biochip, designed with alternating nanolayers of GaAs (12 nm) and AlGaAs (10 nm). Each GaAs–AlGaAs bilayer acts as an independent sensing unit. By employing a specific thiolated aptamer, we achieve efficient detection of <em>Bacillus thuringiensis</em> spp. <em>kurstaki</em> spores. The interaction between the thiolated aptamers with the targeted spores leads to the formation of aptamer-spore hybrids, which bind to the GaAs surface. The GaAs–AlGaAs nanoheterostructure biochip supports multiple biosensing cycles. After consumption of the first GaAs–AlGaAs bilayer, a simple regeneration step with a high ionic strength buffer releases the bound spores and prepares subsequent nanolayers of the same biochip for reuse. The capability to regenerate and reuse individual nanolayers presents a novel and practical solution for reducing biosensor waste while improving operational efficiency. We further explore the conditions necessary for sustainable DIP operation in biochips containing multiple GaAs–AlGaAs nanolayer pairs, ensuring reliable performance over numerous biosensing cycles. Our findings establish a cost-effective and durable biosensing platform. This work marks a significant step toward quasi-autonomous biosensing technologies, paving the way for cost-effective and robust reusable biosensors suitable for remote and field applications.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 5","pages":" 425-431"},"PeriodicalIF":3.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d4sd00367e?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144073551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ahmet Onder, Ferit Begar, Erman Kibris, Onur Buyukcakir and Umit Hakan Yildiz
{"title":"Nitrate sensing with molecular cage ionophores: a potentiometric approach†","authors":"Ahmet Onder, Ferit Begar, Erman Kibris, Onur Buyukcakir and Umit Hakan Yildiz","doi":"10.1039/D4SD00359D","DOIUrl":"https://doi.org/10.1039/D4SD00359D","url":null,"abstract":"<p >Nitrate ions are widespread environmental pollutants in water and soil, posing critical risks to both human health and ecosystems. This study introduces a molecular cage as a novel ionophore for potentiometric nitrate-selective ion-selective electrodes (ISEs) designed for enhanced specificity and sensitivity. Among six synthetic candidates, the electrode incorporating a 1,3,5-tri(<em>p</em>-hydroxyphenyl)benzene-based chlorotriazine pillared cage molecule (CAGE-1) exhibited superior performance, characterized by a linear response in the nitrate concentration range of 1.0 × 10<small><sup>−5</sup></small> to 1.0 × 10<small><sup>−1</sup></small> M, with a high coefficient of determination (<em>R</em><small><sup>2</sup></small> = 0.9971) and a slope of −53.1 ± 1.4 mV dec<small><sup>−1</sup></small>. The electrode also achieved a limit of detection of 7.5 × 10<small><sup>−6</sup></small> M. These findings highlight the potential of molecular cages as ionophores for nitrate sensing in environmental applications.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 5","pages":" 432-442"},"PeriodicalIF":3.5,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d4sd00359d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144073552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}