Article
Spectroscopy
Jie Li
Summary: A study on surface-enhanced Raman scattering (SERS) of guanine is reported by employing colloidal silver nanoparticles modified on the silver electrode as substrate. High-quality SERS spectra with potential dependence were obtained, shedding light on the varying adsorption behavior of guanine on the nano-surface. High-quality SERS spectra have also been obtained for picolinic acid molecules. The good stability and homogeneous size distribution of silver nanoparticle coatings provide a highly SERS-active substrate for detecting DNA-bases and probing their local interactions.
SPECTROSCOPY LETTERS
(2023)
Review
Pharmacology & Pharmacy
Thomas D. Pollard, Jun Jie Ong, Alvaro Goyanes, Mine Orlu, Simon Gaisford, Mohammed Elbadawi, Abdul W. Basit
Summary: Precision medicine has great potential for improving patient quality of life through therapeutic drug monitoring (TDM), with electrochemical biosensors (ECBs) offering a cost-effective, portable, and highly sensitive solution to current TDM challenges. Emerging strategies for continuous drug monitoring are being explored to enhance the field's developments and outlook.
DRUG DISCOVERY TODAY
(2021)
Article
Chemistry, Physical
Mohan Kumar, Yongsheng Fu, Miao Wang, B. E. Kumara Swamy, Gururaj Kudur Jayaprakash, Wei Zhao
Summary: By theoretically studying the frontier molecular orbital and analytical Fukui functions, a CTAB-modified carbon paste electrode (CTCPE) with improved sensitivity for simultaneous detection of guanine, uric acid, and dopamine was successfully fabricated. The electrode demonstrated low detection limits for the biomolecules in mixture and showed good performance for detecting target molecules in real samples. The CTCPE exhibited good repeatability, stability, and selectivity for detecting GU, UA, and DA with high sensitivity.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Chemistry, Physical
Azam Zolfaghari Asl, Amir Abbas Rafati, Sadegh Khazalpour
Summary: Novel screen-printed gold electrodes modified with molecularly imprinted polyphenol were used for the detection of guanine and adenine in the presence of each other. The electrochemical polymerization method was used to synthesize a thin layer of molecularly imprinted polymer on the electrode surface. The fabricated sensors showed high sensitivity, good repeatability, and long-term stability, and were successfully utilized for the measurement of guanine and adenine in human serum samples.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
Chaoyue Liu, Teo Lombardo, Jiahui Xu, Alain C. Ngandjong, Alejandro A. Franco
Summary: The microstructures and electrochemical performance of Lithium Ion Battery electrodes are determined by the manufacturing process parameters. This study presents a 3D-resolved electrochemical model of a NMC111-based electrode, which experimentally verifies the influence of slurry formulation and calendering degree on electrode performance. The findings suggest that the distribution of carbon and binder within the electrode volume, as well as the electrostatic potential difference between the electrode and current collector, play vital roles in determining the electrode performance.
ENERGY STORAGE MATERIALS
(2023)
Article
Electrochemistry
Pandia Rajathi Muthu Krishnan, Arunkumar Sakthivel, Subbiah Alwarappan
Summary: Sulfur-doped graphitic carbon nitride (S-g-C3N4) was used as an electrochemical platform for the selective and sensitive detection of DNA bases. The best detection medium was found to be pH 9.0 PBS buffer, with a low detection limit and high sensitivity. The proposed sensor exhibited stable, selective, and sensitive performance towards individual DNA bases even in the presence of other DNA bases.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Chemistry, Analytical
Ewa Pieta, Czeslawa Paluszkiewicz, Wojciech M. Kwiatek, Maria Rosa Lopez-Ramirez
Summary: This study describes the vibrational properties of the anticancer drug batimastat (BB-94) as an inhibitor of extracellular matrix metalloproteinase and its adsorption on a silver roughened electrode surface using surface-enhanced Raman spectroscopy (SERS). The research reveals that the applied electrode potential and excitation wavelengths greatly influence the molecule-metal interface. By calculating molecular geometry and Raman frequencies, the nature of vibrational modes is clarified, and it is found that certain parts of the molecule interact with the metal surface, resulting in enhanced SERS signal. Additionally, different adsorption species or metal complexes on the surface could contribute to the observed SERS spectra.
Article
Chemistry, Multidisciplinary
Zuoti Xie, Ioan Baldea, Quyen Van Nguyen, C. Daniel Frisbie
Summary: The research demonstrates that metal-molecule-metal junctions based on alkane thiol and oligophenylene thiol exhibit different electrical asymmetry and current rectification ratios, which can be explained by different rectification mechanisms such as the Stark effect and position-dependent coupling. The study highlights key physical mechanisms at play in single step tunneling through molecules, showing quantitative agreement between experiment and theory in these systems.
Article
Chemistry, Analytical
Katarzyna W. Egrzyn, Agata Michalska, Krzysztof Maksymiuk
Summary: A novel solid contact material, tungsten trioxide, is proposed for an all-solid-state potassium-selective electrode with a poly(vinyl chloride) based membrane. It offers advantages such as mitigating the thin water layer effect and enhancing electroactivity due to its hydrophilicity. The proposed sensor exhibits excellent analytical performance with a wide linear response range, low detection limit, and high selectivity. The low frequency capacitance of the solid contact is higher than that of a coated wire sensor and is not diminished when covered by the membrane.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Electrochemistry
Jiawen Xu, Yufei Wang, Zhou Sha, Yanpei Chen, Changjiang Sun, Hai-Ying Gu
Summary: The direct electrochemistry of hepatitis B virus containing covalently closed circular DNA (HBV cccDNA) was achieved using a pretreated glassy carbon electrode (PGCE). Microwave irradiation was used to capture the direct electron transfer of guanine (G) and adenine (A) on the HBV cccDNA strand, melting the cccDNA into single-stranded DNA. Cyclic voltammetry revealed the irreversible adsorption and diffusion-controlled processes of G and A, with G involving 2 protons and 2 electrons, while A only involved 2 electrons.
Article
Engineering, Industrial
Shunda Zhan, Yonghua Zhao
Summary: A novel gas-assisted electrochemical micromachining (GA-ECM) method is proposed in this study to enhance ECM precision by utilizing a gas shielding tool electrode. The method is proven to effectively suppress stray machining and improve machining accuracy through simulations and experiments.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2021)
Article
Chemistry, Physical
Ding-Yuan Kuo, Xinyao Lu, Bintao Hu, Hector D. Abruna, Jin Suntivich
Summary: The formation of surface-bound hydrogen is significantly faster in acid compared to base, with a reaction-order analysis indicating a standard proton-coupled electron transfer reaction in acid and a pH-independent rate constant in base, suggesting a chemical step involving the reorganization of interfacial water.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Zeyuan Sun, Brian Khau, Hao Dong, Christopher J. Takacs, Shuhan Yuan, Mengting Sun, Bar Mosevitzky Lis, Dang Nguyen, Elsa Reichmanis
Summary: This study presents a new design for organic mixed ionic electronic conductors (OMIECs) by functionalizing polythiophenes. The materials exhibit improved water processability and solvent resistance due to carboxylic acid functionalization and variation in alkyl spacer length. Advanced techniques were used to investigate the microstructure, ionic-electronic coupling, and operational stability of the materials. The materials showed significant potential in organic electrochemical transistors, highlighting their application prospects.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Zhiwei Wu, Shulong Li, Weiqiang Wang, Ning Wang, Tao Zhou
Summary: CrSiCN coatings with a composite structure were successfully deposited on glass and Si(100) substrates using unbalanced magnetron sputtering. The coatings consisted of Cr(C, N) nanocrystals embedded in an amorphous matrix. The dry electrode deposited at a bias voltage of -60V exhibited excellent electrochemical noise performance and lower contact impedance, making it suitable for use as a dry electrode.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Materials Science, Multidisciplinary
Zhiwei Wu, Shulong Li, Ning Wang, Tao Zhou
Summary: Bio-electrode Cr-Si-C-N coatings were fabricated via unbalanced magnetron sputtering and characterized by XRD, SEM and nano-indentation. The coatings showed a composite structure with Cr(C, N) nanocrystals embedded in an amorphous matrix. The mechanical properties and corrosion resistance of the coatings were influenced by factors such as graphite target current, Si target power, N2 flow and silicon content. The coatings with high Si target power exhibited a decrease followed by an increase in OCP and contact resistance, while those with high N2 flow and graphite target current showed lower OCP and poorer corrosion resistance.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Simona Ranallo, Daniela Sorrentino, Elisabetta Delibato, Gianfranco Ercolani, Kevin W. Plaxco, Francesco Ricci
Summary: Here we report the design and optimization of an antibody-responsive, DNA-based device that enables communication between non-interacting proteins. The device recognizes and binds a specific antibody, causing a conformational change that releases a DNA strand regulating the activity of a target protein. We demonstrate the antibody-induced control of thrombin and Taq DNA polymerase, showcasing the versatility of this strategy in regulating protein-protein communication in artificial networks.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Correction
Chemistry, Multidisciplinary
Alexander Shaver, Nandini Kundu, Brian E. Young, Philip A. Vieira, Jonathan T. Sczepanski, Netzahualcoyotl Arroyo-Curras
Article
Chemistry, Multidisciplinary
Elissa K. Leonard, Miguel Aller Pellitero, Boris Juelg, Jamie B. Spangler, Netzahualcoyotl Arroyo-Curras
Summary: Rapid and accurate diagnostics are crucial for controlling the COVID-19 pandemic and future infectious disease outbreaks. Researchers have developed a novel enzymatic reporter that can detect disease-specific antibodies by producing glucose when binding to patient antibodies. The fusion protein used in this method has shown precise agreement with commercial immunoassays, making it a versatile tool for detecting disease-specific antibodies.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Chemistry, Physical
Elodie V. d'Astous, Philippe Dauphin-Ducharme
Summary: The article discusses the signal transduction mechanisms of electrochemical host-guest sensing, explores the advantages and shortcomings of this method, and hopes to promote the development of commercial electrochemical devices based on host-guest chemistry.
CURRENT OPINION IN ELECTROCHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Vincent Clark, Kelly Waters, Ben Orsburn, Namandje N. Bumpus, Nandini Kundu, Jonathan T. Sczepanski, Partha Ray, Netzahualcoyotl Arroyo-Curras
Summary: Human cyclophilin B (CypB) is oversecreted by pancreatic cancer cells and can be used as a potential biomarker for early-stage disease diagnosis. This research used ultrasensitive electrochemical sensors to measure the hydrolytic activity of CypB, providing evidence that CypB can cleave nucleic acids. Future development of CypB bioassays will require the use of nuclease-resistant aptamer sequences.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Biochemical Research Methods
Yuyang Wu, Simona Ranallo, Erica Del Grosso, Alejandro Chamoro-Garcia, Herbert L. Ennis, Nenad Milosavic, Kyungae Yang, Tod Kippin, Francesco Ricci, Milan Stojanovic, Kevin W. Plaxco
Summary: Electrochemical aptamer-based (EAB) sensors utilize conformational changes to transduce target recognition into electrochemical output, supporting high-frequency molecular measurements and working in complex environments. However, modification of the aptamer is required to achieve the necessary conformational change and balance affinity and signal gain.
BIOCONJUGATE CHEMISTRY
(2023)
Article
Chemistry, Analytical
Miguel Aller Pellitero, Nandini Kundu, Jonathan Sczepanski, Netzahualcoyotl Arroyo-Curras
Summary: DNA-based electrochemical sensors use Os(ii/iii) complex as a redox reporter, which shows pH-insensitive electron transfer and better operational stability compared to methylene blue, making it a promising candidate for continuous molecular monitoring applications.
Article
Biochemical Research Methods
Claudio Parolo, Andrea Idili, Jason Heikenfeld, Kevin W. Plaxco
Summary: The functionality of lab on a chip (LOC) devices has expanded in recent years, providing scientists and developers with versatile platforms for various chemical and biological applications. However, real-time molecular measurements, which are crucial for guiding chemical responses, are still lacking in this field. Among the general sensing strategies, those relying on binding-induced conformational change of bioreceptors are expected to be the most successful in providing LOCs with real-time molecular monitoring capabilities.
Article
Chemistry, Multidisciplinary
Philippe Dauphin-Ducharme, Zachary R. Churcher, Aron A. Shoara, Erfan Rahbarimehr, Sladjana Slavkovic, Nicolas Fontaine, Olivia Boisvert, Philip E. Johnson
Summary: Electrochemical aptamer-based (E-AB) biosensors have the capability to monitor molecules directly in complex matrices and in the body. However, there is limited evidence demonstrating conformational change in E-AB sensors. In this study, it was found that the signal transduction mechanism of the cocaine-binding aptamer relies on a redox-reporter - ligand competition mechanism rather than a ligand-induced structure formation mechanism.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Multidisciplinary Sciences
Julian Gerson, Murat Kaan Erdal, Matthew H. McDonough, Kyle L. Ploense, Philippe Dauphin-Ducharme, Kevin M. Honeywell, Kaylyn K. Leung, Netzahualcoyotl Arroyo-Curras, Jenny M. Gibson, Nicole A. Emmons, Wendy Meiring, Joao P. Hespanha, Kevin W. Plaxco, Tod E. Kippin
Summary: In this study, electrochemical aptamer-based sensors were used to achieve real-time measurement of drug concentrations in the brains of freely moving rats. The results showed that the sensors can provide high-resolution, seconds-resolved neuropharmacokinetics and concentration-response relations of individual subjects. Additionally, a closed-loop feedback-controlled drug delivery system was employed to maintain stable intracranial drug levels.
Review
Infectious Diseases
Ruvimbo Dephine Mishi, Michael Andrew Stokes, Craig Anthony Campbell, Kevin William Plaxco, Sophie Lena Stocker
Summary: Therapeutic drug monitoring (TDM) is important for optimizing drug exposure in critically ill patients. This paper explores the potential of biosensors as a solution to current challenges in measuring plasma drug concentrations and discusses their application in TDM of antibiotics. The authors argue that biosensors hold great promise for enhancing drug exposure optimization in critically ill patients.
Article
Biochemical Research Methods
Mark Friedel, Benjamin Werbovetz, Amy Drexelius, Zach Watkins, Ahilya Bali, Kevin W. Plaxco, Jason Heikenfeld
Summary: The ability to continuously collect diagnostic information from the body during daily activity has revolutionized health and disease monitoring. This study presents the first report of real-time human molecular data collected using electrochemical aptamer sensors, demonstrating their ability to measure the concentration of phenylalanine in dermal interstitial fluid after an oral bolus. The study also achieves an important milestone in moving such sensors to the clinic by demonstrating 90 days dry room-temperature shelf storage.
Article
Chemistry, Analytical
Kaylyn K. Leung, Julian Gerson, Nicole Emmons, Brian Roehrich, Elsi Verrinder, Lisa C. Fetter, Tod E. Kippin, Kevin W. Plaxco
Summary: Electrochemical, aptamer-based (EAB) sensors are a versatile molecular monitoring technology that can achieve high-frequency, real-time measurements within the living body. The positioning of the electrodes within or outside the catheter significantly affects the performance of the sensor, with external placement improving signal-to-noise ratio. The size of the counter electrode does not need to be larger than the working electrode. These findings have implications for the design of various electrochemical biosensors.
Article
Chemistry, Analytical
Erfan Rahbarimehr, Hoi Pui Chao, Zachary R. Churcher, Sladjana Slavkovic, Yunus A. Kaiyum, Philip E. Johnson, Philippe Dauphin-Ducharme
Summary: Electrochemical aptamer-based (E-AB) biosensors provide real-time measurements of molecule concentrations and have potential applications in personalized medicine. However, some E-AB sensors interrogated with square-wave voltammetry show lower aptamer affinity compared to solution techniques such as isothermal titration calorimetry (ITC). We hypothesized that the difference in dissociation constants measured with solution techniques and square-wave voltammetry may be due to the electrochemical interrogation technique itself. Our results showed that electrochemical impedance spectroscopy can accurately measure dissociation constants, unlike square-wave voltammetry.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Alejandro Chamorro-Garcia, Claudio Parolo, Gabriel Ortega, Andrea Idili, Joshua Green, Francesco Ricci, Kevin W. Plaxco
Summary: Biosensors and bioassays that use proteins and nucleic acids to detect specific molecular targets have limitations in sensitivity to small variations in target concentration. This study introduces the sequestration mechanism to improve the responsiveness of these technologies, narrowing the dynamic range and enhancing the ability to measure small changes in target concentration.