Sensors & diagnostics最新文献

{"title":"A genetically encoded probe for monitoring and detection of iron in real-time†","authors":"Neha Soleja and Mohd. Mohsin","doi":"10.1039/D4SD00091A","DOIUrl":"10.1039/D4SD00091A","url":null,"abstract":"<p >Iron, the most abundant transition metal in the body, regulates cellular function but can be harmful in excess, leading to reactive oxygen species production and cellular damage. Intracellular Fe<small>²⁺</small> exerts a significant impact on cellular function, potentially contributing to various critical diseases. To address this, detection methods need high selectivity, sensitivity, and real-time monitoring capabilities, essential for comprehending disease progression. This necessitates advancements beyond conventional detection approaches. Frataxin, a crucial mitochondrial protein, is indispensable for sustaining life, contributing not only to iron metabolism but also to the formation of iron–sulfur clusters critical for cellular function. Its deficiency is implicated in neurodegenerative diseases. We have developed a nanosensor, based on fluorescence resonance energy transfer (FRET), designed to probe iron efflux mechanisms and facilitate dynamic monitoring of iron concentration and its spatial distribution within living cells. To construct this nanosensor, we strategically positioned CyaY, a bacterial frataxin ortholog, between ECFP and Venus, forming a FRET pair. This innovative nanosensor, designated as FeOS (iron optical sensor), demonstrates exceptional selectivity for iron and maintains stability under physiological pH conditions. Additionally, we engineered three mutant variants: I17C, AD10-I17C, and D76H, with A10D-I17C displaying the highest affinity for iron and a broad detection range. The distinguishing feature of this sensor is that it is genetically encoded, facilitating real-time detection of iron levels within living cells.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 10","pages":" 1714-1723"},"PeriodicalIF":3.5,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00091a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182017","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":"Computationally predicting the performance of gas sensor arrays for anomaly detection†","authors":"Paul Morris and Cory M. Simon","doi":"10.1039/D4SD00121D","DOIUrl":"10.1039/D4SD00121D","url":null,"abstract":"<p >In many gas sensing tasks, we simply wish to become aware of gas compositions that deviate from normal, “business-as-usual” conditions. We provide a methodology, illustrated by example, to computationally predict the performance of a gas sensor array design for detecting anomalous gas compositions. Specifically, we consider a sensor array of two zeolitic imidazolate frameworks (ZIFs) as gravimetric sensing elements for detecting anomalous gas compositions in a fruit ripening room. First, we define the probability distribution of the concentrations of the key gas species (CO<small>₂</small>, C<small>₂</small>H<small>₄</small>, H<small>₂</small>O) we expect to encounter under normal conditions. Next, we construct a thermodynamic model to predict gas adsorption in the ZIF sensing elements in response to these gas compositions. Then, we generate a synthetic training data set of sensor array responses to “normal” gas compositions. Finally, we train a support vector data description to flag anomalous sensor array responses and test its false alarm and missed-anomaly rates under conceived anomalies. We find the performance of the anomaly detector diminishes with (i) greater variance in humidity, which can mask CO<small>₂</small> and C<small>₂</small>H<small>₄</small> anomalies or cause false alarms, (ii) higher levels of noise emanating from the transducers, and (iii) smaller training data sets. Our exploratory study is a step towards computational design of gas sensor arrays for anomaly detection.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 10","pages":" 1699-1713"},"PeriodicalIF":3.5,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00121d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182019","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":"Nonwoven-fabric-based microfluidic devices for solution viscosity measurements†","authors":"Mayumi Otoba Uno, Mariko Omori and Kenji Sakamoto","doi":"10.1039/D4SD00188E","DOIUrl":"https://doi.org/10.1039/D4SD00188E","url":null,"abstract":"<p >Microfluidic chips designed to measure viscosity with extremely small amounts of liquids are expected to examine biological fluids, such as for the prediction of disease states and stress assessment, and for the evaluation of the physical properties of novel synthetic materials. However, these devices typically require sample volumes of several tens of μL or more, which has limitations when collecting biological samples from individuals nearly non-invasively. In this study, we fabricated a flow channel on a nonwoven fabric substrate with tailored hydrophilic and hydrophobic properties to enable viscosity measurements with the small-volume flow of aqueous solutions, such as 3 μL of saline. By measuring the electrical conductivity of the liquid using comb-shaped printed electrodes in contact with the flow path, we quantified the time and distance of liquid flow driven by capillary action to estimate solution viscosity. Using a mixture of glycerol and saline solution with varying viscosities, while maintaining a constant ion concentration, we demonstrated the capability to assess the relative viscosity of solutions. This was achieved by evaluating the correlation coefficient between the flow time and distance, and the net electrical conductivity, which is influenced by the viscosity and ion concentration of the solutions. This study lays the groundwork for developing a low-cost technique to measure the viscosity of solutions with a few μL, offering potential for routine health monitoring and disease prevention.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 9","pages":" 1551-1561"},"PeriodicalIF":3.5,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00188e?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142169807","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":"Selection of DNA aptamers for sensing drugs treating eye disease: atropine and timolol maleate†‡","authors":"Ka-Ying Wong, Yibo Liu, Chau-Minh Phan, Lyndon Jones, Man-Sau Wong and Juewen Liu","doi":"10.1039/D4SD00223G","DOIUrl":"10.1039/D4SD00223G","url":null,"abstract":"<p >Effective monitoring of ocular drugs is crucial for personalized medicine and improving drug delivery efficacy. However, traditional methods face difficulties in detecting low drug concentrations in small volumes of ocular fluid, such as that found on the ocular surface. In this study, we used capture-SELEX to select aptamers for two commonly used ocular drugs, timolol maleate and atropine. We identified TMJ-1 and AT-1 aptamers with binding affinities of 3.4 μM timolol maleate and 10 μM atropine, respectively. Our label-free TMJ-1 biosensor using thioflavin T staining achieved a limit of detection (LOD) of 0.3 μM for timolol maleate. The AT-1 biosensor showed an LOD of 1 μM for atropine, and exhibited a 10-fold higher sensitivity compared to UV-visible spectroscopy. Future research in this area holds promise in enhancing drug delivery monitoring and improving the treatment of ocular diseases.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 10","pages":" 1679-1688"},"PeriodicalIF":3.5,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00223g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182018","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":"Wearable strain sensors: design shapes, fabrication, encapsulation and performance evaluation methods","authors":"Nur Nazihah Abu Hassan Zahri, Anis Nurashikin Nordin, Norsinnira Zainul Azlan, Ibrahim Hafizu Hassan, Lun Hao Tung, Lai Ming Lim and Zambri Samsudin","doi":"10.1039/D4SD00190G","DOIUrl":"10.1039/D4SD00190G","url":null,"abstract":"<p >Highly durable, stretchable, sensitive and biocompatible wearable strain sensors are crucial for healthcare, sports, and robotic applications. While strain sensor designs, fabrication and testing methods have been widely discussed by researchers, not many have discussed sensor improvements <em>via</em> implementing designs and protection layers that make the sensor more resilient. This paper will focus on sensor designs (straight line, U-shape, serpentine, and kirigami) and material selection that can provide better performance. Theoretical equations and calculations to indicate how the design shapes contribute to providing better performance are also included. An important aspect which is not often explored is having encapsulation layers which can significantly reduce the formation of cracks when the sensor is subjected to mechanical stress and bending. This review will include post-fabrication steps that are necessary to incorporate protection layers for wearable sensors. Due to the curvilinear shapes of wearable sensors that often need to be in close contact with human skin, reliability and durability testing often differs greatly from that of traditional strain sensors. Recent techniques for performance evaluation specific to wearable sensors such as cyclic stretching, bending, stretch till failure, washability, signal latency, and tensile tests were also discussed in detail. This includes experimental setup and duration of testing and its significance was described. To ensure device safety for the user, biocompatibility assessments need to be made. In this review, cytotoxicity test methods such as trypan blue, cell proliferation and MTT assay were compared and evaluated. By consolidating recent developments, this paper aims to provide researchers and practitioners with a comprehensive understanding of the advancements, and future directions in this rapidly evolving field.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 10","pages":" 1635-1650"},"PeriodicalIF":3.5,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00190g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944543","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":"3D-printed electrochemical cells for multi-point aptamer-based drug measurements†","authors":"John Mack, Raygan Murray, Kenedi Lynch and Netzahualcóyotl Arroyo-Currás","doi":"10.1039/D4SD00192C","DOIUrl":"10.1039/D4SD00192C","url":null,"abstract":"<p >Electrochemical aptamer-based (E-AB) sensors achieve detection and quantitation of biomedically relevant targets such as small molecule drugs and protein biomarkers in biological samples. E-ABs are usually fabricated on commercially available macroelectrodes which, although functional for rapid sensor prototyping, can be costly and are not compatible with the microliter sample volumes typically available in biorepositories for clinical validation studies. Seeking to develop a multi-point sensing platform for sensor validation in sample volumes characteristic of clinical studies, we report a protocol for in-house assembly of 3D-printed E-ABs. We employed a commercially available 3D stereolithographic printer (FormLabs, $5k USD) for electrochemical cell fabrication and directly embedded electrodes within the 3D-printed cell structure. This approach offers a reproducible and reusable electrode fabrication process resulting in four independent and simultaneous measurements for statistically weighted results. We demonstrate compatibility with aptamer sequences binding antibiotics and antineoplastic agents. We also demonstrate a proof-of-concept validation of serum vancomycin measurements using clinical samples. Our results demonstrate that 3D-printing can be used in conjunction with E-ABs for accessible, rapid, and statistically meaningful validation of E-AB sensors in biological matrices.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 9","pages":" 1533-1541"},"PeriodicalIF":3.5,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00192c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944595","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":"A fast and highly selective ECL creatinine sensor for diagnosis of chronic kidney disease†","authors":"Hosein Afshary and Mandana Amiri","doi":"10.1039/D4SD00165F","DOIUrl":"10.1039/D4SD00165F","url":null,"abstract":"<p >Monitoring of creatinine in human fluid has attracted considerable attention owing to the potential for diagnosis of chronic kidney disease. However, the detection of creatinine has been difficult owing to its electrochemical and optical inertness. In this approach, a highly selective and sensitive electrochemiluminescence (ECL) strategy based on homogeneous carbon quantum dots (CQDs) for the detection of creatinine was introduced. A copper(<small>II</small>) picrate complex was added at the surface of electrode to improve the selectivity of the sensor significantly by the formation of a Janovsky complex. A multi-pulse amperometric technique was applied as a very fast and reliable method for quantitative determination of creatinine. The calibration curve was acquired with a linear range from 1.0 × 10<small>⁻⁸</small> to 1 × 10<small>⁻⁵</small> M with a low detection limit of 8.7 × 10<small>⁻⁹</small> M. The proposed creatinine sensing platform is experimentally very simple and shows high selectivity with a broad linear range of detection. Furthermore, the presented method can determine creatinine in real samples with excellent recoveries.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 9","pages":" 1562-1570"},"PeriodicalIF":3.5,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00165f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944545","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":"Optimization of solvents, electrolytes, and mediators for polyindole-based electrochemical sensors","authors":"P. C. Pandey, Atul Kumar Tiwari and Roger J. Narayan","doi":"10.1039/D4SD00175C","DOIUrl":"10.1039/D4SD00175C","url":null,"abstract":"<p >Surface-engineered conducting polymers (CPs) have enabled technological advances in chemistry and materials science. Heterocyclic conjugated organic molecules, specifically indole and its derivatives, have the potential to be polymerized under electrochemically controlled conditions in different types of compatible solvent media, including self-assembled nanofluids, for several applications. Polymer-based electrode materials are valuable for the detection of various targeted biomolecules and other analytes. This review outlines the evolution of the electropolymerization technique in recent years, along with developments in the field. With advances in nanoscience, several materials have been used to modify CPs for electrochemical sensing. Several biomedical applications and the role of antifouling agents in the properties of several electropolymerized thin films are highlighted.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 9","pages":" 1392-1405"},"PeriodicalIF":3.5,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00175c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141886929","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":"Electrochemical detection of tumor cells based on proximity labelling-assisted multiple signal amplification†","authors":"Guozhang Zhou, Fei Zhou, Xiaomeng Yu, Daiyuan Zhou, Jiaqi Wang, Bing Bo, Ya Cao and Jing Zhao","doi":"10.1039/D4SD00217B","DOIUrl":"10.1039/D4SD00217B","url":null,"abstract":"<p >Malignant tumors are the second leading cause of human deaths worldwide, and early cancer screening and diagnosis can effectively reduce cancer mortality. Herein, we propose a new electrochemical method for the highly sensitive detection of MUC1-positive tumor cells based on proximity labelling-assisted multiple signal amplification. Specifically, a MUC1 aptamer-modified electrode was prepared for capturing MUC1-positive tumor cells, followed by binding of G4-DNA strands to the cells with the aid of a mild reduction reaction. A hemin/G4-DNA complex was then formed and acted as a mimic of horseradish peroxidase, catalysing the proximal labelling of tyramine-modified gold nanoparticles to induce silver-enhanced electrochemical signal amplification. Electrochemical results demonstrated that the method was able to specially identify MUC1-positive tumor cells and generate corresponding electrochemical responses in the range of 100 cells per mL to 1 × 10<small>⁶</small> cells per mL with a detection limit of 21 cells per mL. Furthermore, the method displayed good stability and anti-interference performance in complex serum environments. Therefore, our work may provide an effective tool to improve the accuracy of cell-based tissue examination and liquid biopsy for early diagnosis of cancers in the future.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 9","pages":" 1542-1550"},"PeriodicalIF":3.5,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00217b?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141882057","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":"Direct writing of graphene electrodes for point-of-care electrochemical sensing applications","authors":"Lei Zhao, Andrew Piper, Giulio Rosati and Arben Merkoçi","doi":"10.1039/D4SD00140K","DOIUrl":"10.1039/D4SD00140K","url":null,"abstract":"<p >Electrochemical sensors are increasingly garnering attention as valuable tools for point-of-care (POC) testing due to their low costs, high sensitivities, and ease of miniaturization. Graphene-based materials, renowned for their tunable electrical conductivity, high specific surface areas, versatile functionality, and biocompatibility; are highly suited for the fabrication of electrochemical sensors with heightened sensitivities. Non-contact, maskless, direct writing methods allow the rapid, large-scale production of graphene electrodes with high design flexibility. Researchers globally are advancing graphene electrode production, aiming for smaller, faster, and more efficient sensors. This review provides a comprehensive overview of recent advances on the direct writing of graphene electrodes for electrochemical sensing applications. It covers the basics of direct writing techniques, the advancements in graphene ink/precursor preparation, structural design, and device integration, with a focus on POC platforms.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 9","pages":" 1406-1427"},"PeriodicalIF":3.5,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/sd/d4sd00140k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141867834","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}