ABSTRACT
Clinical photographic documentation is recommended as part of the standardized clinical evaluation of traumatized patients according to the most current International Association of Dental Traumatology guidelines for the management of traumatic dental injuries (TDIs), published in 2020. The use of current technology such as mobile smartphones and the emergence of teledentistry for direct communication between dentists and with patients have increased the need to improve the knowledge and skills for contemporary clinical photographic documentation procedures at the dental office as well as at the accident site. The purpose of this review is to include findings from the available literature and discuss modern techniques, contemporary equipment, accessories and developments that can be used by both patients and dental professionals for proper clinical documentation after TDIs. Emphasis is given on the positioning and patient management based on the type and severity of the injury, and the selection of the appropriate technique. Moreover, the number and type of clinical photographs for each dental trauma scenario, the suggested timeline for optimal photographic documentation as well as legal considerations involved are also discussed.
ABSTRACT
The effect of the sol-gel microenvironment on the activity of acetylcholinesterase, an enzyme of high bio-analytical interest, is presented and is correlated to the overall analytical performance of corresponding biosensors. The sol-gel membranes are initially optimized with respect to the catalyst and the TEOS:H2O ratio (r), for mechanical stability, porosity, and hydrophobicity as well as in terms of enzymatic activity. FT-IR and electrochemical impedance spectroscopy (EIS) are used to probe the configuration and rotational mobility of the enzyme within the sol-gel matrices. Overall, it is observed that the rotational mobility of the protein can be correlated with the sensitivity of the biosensor. Optimum biosensor performance is obtained for base-catalyzed sol-gels with r values close to 2. The biosensor has sensitivity of 2.5 microA/mm, a linear range of response between 1 and 3mm, response time of about 30s, and sensor-to-sensor reproducibility (RSD) of 3%. These analytical characteristics are far superior to previously reported sol-gel biosensors.
Subject(s)
Acetylcholinesterase/chemistry , Biocompatible Materials , Biosensing Techniques , Calibration , Catalysis , Cell Membrane/metabolism , Dose-Response Relationship, Drug , Electrochemistry , Electrodes , Microscopy, Electron, Scanning , Phase Transition , Spectrophotometry , Spectroscopy, Fourier Transform Infrared , Time Factors , Water/chemistryABSTRACT
The design of a biosensor for the detection of dichlorvos at attomolar levels is described based on a highly sensitive double mutant (E69Y Y71D) of the Drosophila melanogaster acetylcholinesterase (Dm. AChE). This enzyme has a k(i) for dichlorvos equal to 487 microM(-1)min(-1), which is 300 and 20,000 times higher than that of the wild type Dm. AChE and the Electrophorus electricus AChE (E.el. AChE), respectively. The enzyme is immobilized into microporous-activated conductive carbon, and is used as such for the development of an inhibitor electrochemical biosensor. This E69Y Y71D mutant enables the decrease in the detection limit of the biosensor down to 10(-17) M, which is five orders of magnitude lower compared to the Electropharus electricus-based biosensor and eight orders of magnitude lower than the biosensors described so far.
Subject(s)
Acetylcholinesterase/chemistry , Acetylcholinesterase/genetics , Biosensing Techniques/instrumentation , Dichlorvos/analysis , Drosophila melanogaster/enzymology , Drosophila melanogaster/genetics , Protein Engineering/methods , Acetylcholinesterase/analysis , Animals , Biosensing Techniques/methods , Environmental Monitoring/instrumentation , Environmental Monitoring/methods , Enzyme Activation , Enzyme Stability , Microchemistry/instrumentation , Microchemistry/methods , Pesticides/analysis , Recombinant Proteins/analysis , Recombinant Proteins/chemistryABSTRACT
In this study we present the results obtained from efforts to stabilize the inherently unstable m-AChE in nanoporous materials, for the development of biosensors with increased operational stability. Based on existing theoretical models, the entrapment of proteins into relatively small rigid cages drastically increases the stability of these proteins, as this is manifested by their decreased tendency to unfold. The use of two different meso/nanomaterials for the immobilization of the m-AChE shows that there is both a decrease in the leaching of the protein from the biosensor membrane to the test solution, as well as a drastic increase in the operational stability of the resulting biosensor.
Subject(s)
Acetylcholinesterase/analysis , Acetylcholinesterase/chemistry , Biosensing Techniques/methods , Nanostructures/chemistry , Nanostructures/ultrastructure , Coated Materials, Biocompatible/analysis , Coated Materials, Biocompatible/chemistry , Enzyme Activation , Enzyme Stability , Enzymes, Immobilized/analysis , Enzymes, Immobilized/chemistry , Materials Testing , PorosityABSTRACT
Aligned multi-wall carbon nanotubes (MWNT) grown on platinum substrate are used for the development of an amperometric biosensor. The opening and functionalization by oxidation of the nanotube array allows for the efficient immobilization of the model enzyme, glucose oxidase. The carboxylated open-ends of nanotubes are used for the immobilization of the enzymes, while the platinum substrate provides the direct transduction platform for signal monitoring. It is also shown that carbon nanotubes can play a dual role, both as immobilization matrices and as mediators, allowing for the development of a third generation of biosensor systems, with good overall analytical characteristics.