Chemical and Biochemical Sensors

Abstract

The article contains sections titled: 1. Introduction to the Field of Sensors and Actuators 2. Chemical Sensors 2.1. Introduction 2.2. Molecular Recognition Processes and Corresponding Selectivities 2.2.1. Catalytic Processes in Calorimetric Devices 2.2.2. Reactions at Semiconductor Surfaces and Interfaces Influencing Surface or Bulk Conductivities 2.2.3. Selective Ion Conductivities in Solid‐State Materials 2.2.4. Selective Adsorption ‐ Distribution and Supramolecular Chemistry at Interfaces 2.2.5. Selective Charge‐Transfer Processes at Ion‐Selective Electrodes (Potentiometry) 2.2.6. Selective Electrochemical Reactions at Working Electrodes (Voltammetry and Amperometry) 2.2.7. Molecular Recognition Processes Based on Molecular Biological Principles 2.3. Transducers for Molecular Recognition: Processes and Sensitivities 2.3.1. Electrochemical Sensors 2.3.1.1. Self‐Indicating Potentiometric Electrodes 2.3.1.2. Voltammetric and Amperometric Cells 2.3.1.3. Conductance Devices 2.3.1.4. Ion‐Selective Field‐Effect Transistors (ISFETs) 2.3.2. Optical Sensors 2.3.2.1. Fiber‐Optical Sensors 2.3.2.2. Integrated Optical Chemical and Biochemical Sensors 2.3.2.3. Surface Plasmon Resonance 2.3.2.4. Reflectometric Interference Spectroscopy 2.3.3. Mass‐Sensitive Devices 2.3.3.1. Introduction 2.3.3.2. Fundamental Principles and Basic Types of Transducers 2.3.3.3. Theoretical Background 2.3.3.4. Technical Considerations 2.3.3.5. Specific Applications 2.3.3.6. Conclusions and Outlook 2.3.4. Calorimetric Devices 2.4. Problems Associated with Chemical Sensors 2.5. Multisensor Arrays, Electronic Noses, and Tongues 3. Biochemical Sensors (Biosensors) 3.1. Definitions, General Construction, and Classification 3.2. Biocatalytic (Metabolic) Sensors 3.2.1. Monoenzyme Sensors 3.2.2. Multienzyme Sensors 3.2.3. Enzyme Sensors for Inhibitors ‐ Toxic Effect Sensors 3.2.4. Biosensors Utilizing Intact Biological Receptors 3.3. Affinity Sensors ‐ Immuno‐Probes 3.3.1. Direct‐Sensing Immuno‐Probes without Marker Molecules 3.3.2. Indirect‐Sensing Immuno‐Probes using Marker Molecules 3.4. Whole‐Cell Biosensors 3.5. Problems and Future Prospects 4. Actuators and Instrumentation 5. Future Trends and Outlook

Analytical Techniques for Analyzing Thermally Degraded Monoethylene Glycol with Methyl Diethanolamine and Film Formation Corrosion Inhibitor

“…Reliable and accurate electrical conductivity measurements depend on a number of factors, such as the concentration and mobility of ions, the presence of organic alcohols and sugars, the valence of ions, temperature, etc. 33 Bonyad et al 34 analyzed salt-organic inhibitor concentrations via electrical conductivity measurements for samples taken from a MEG regeneration unit, offshore platform inlet, and slug-catcher outlet. Degraded MEG solutions and corrosion inhibitor additives influence the thermodynamic gas hydrate stability.…”

“…the ability of an aqueous solution to carry an electrical current, is an extremely widespread and useful monitoring method, especially for quality control purposes. Reliable and accurate electrical conductivity measurements depend on a number of factors, such as the concentration and mobility of ions, the presence of organic alcohols and sugars, the valence of ions, temperature, etc . Bonyad et al analyzed salt-organic inhibitor concentrations via electrical conductivity measurements for samples taken from a MEG regeneration unit, offshore platform inlet, and slug-catcher outlet.…”

Influence of Regenerated Monoethylene Glycol on Natural Gas Hydrate Formation

“…Electrical conductivity (σ), which is the ability of a solution to carry an electric current, is a well-recognized measurement for evaluating salt concentrations in the MEG solution. , Thus, electrical conductivities for scenarios were measured ( Figure ) and found to respond proportionally to the cation concentration. The electrical conductivity of scenario B2 showed the highest value (8620 μ S/cm), corresponding well to the high cation concentrations (15231 ppm), followed by scenario F1.…”

Measuring Molecular Junctions: What Is the Standard?

“…The CT-AFM measurement technique can be expanded to study transport across bilayer junctions, the contact between multiple molecular layers, that is, one molecule on the substrate and the second on the CT-AFM tip. , Such a configuration is a nanometer-scale version of the electronic tongue, which would reveal chemical information at the molecular scale and form an ultrasensitive chemical detector.…”