Saliva has been recently proposed as an alternative to classic biofluid analyses due to both availability and reliability regarding the evaluation of various biomarkers. Biosensors have been designed ...for the assessment of a wide spectrum of compounds, aiding in the screening, diagnosis, and monitoring of pathologies and treatment efficiency. This literature review aims to present the development in the biosensors research and their utility using salivary assessment.
a comprehensive literature search has been conducted in the PubMed database, using the keywords "saliva" and "sensor". A two-step paper selection algorithm was devised and applied.
The 49 papers selected for the present review focused on assessing the salivary biomarkers used in general diseases, oral pathologies, and pharmacology. The biosensors proved to be reliable tools for measuring the salivary levels of biochemical metabolic compounds such as glucose, proteinases and proteins, heavy metals and various chemical compounds, microorganisms, oncology markers, drugs, and neurotransmitters.
Saliva is a biofluid with a significant clinical applicability for the evaluation and monitoring of a patient's general health. Biosensors designed for assessing a wide range of salivary biomarkers are emerging as promising diagnostic or screening tools for improving the patients' quality of life.
A highly sensitive, selective, fast and stable electrochemical aptasensor, based on a screen-printed carbon electrode modified with a nanocomposite architecture consisting of polypyrrole and gold ...nanoparticles was designed for interleukin6 detection in human serum. The simultaneous presence of the conductive polymer and gold at the electrode surface provided a suitable environment for the interleukin6 specific aptamer immobilization of through sulfur-gold bonding. Cyclic voltammetry and electrochemical impedance spectroscopy were used for the monitoring, characterization and optimization of the biosensor during all the steps involved in the fabrication process. After complete optimization, the aptasensor exhibited a good impedimetric response towards the target analyte. The results showed that interleukin6 could be detected in a wide linear range from 1 pg mL−1 to 15 μg mL−1 with a detection limit of 0.33 pg mL−1. The biosensor was tested in the presence of other proteins in human serum samples with good recoveries.
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•An label free aptasensor for sensitive detection of Interleukin 6 is presented.•The linear domain for IL6 detection was from 1 pg mL−1 to 15 μg mL−1.•The aptasensor was applied for serum samples with a detection limit of 0.33 pgmL−1.
Wearable bendable bandage-based sensor and a minimally invasive microneedle biosensor are described toward rapid screening of skin melanoma. These wearable electrochemical sensors are capable of ...detecting the presence of the tyrosinase (TYR) enzyme cancer biomarker in the presence of its catechol substrate, immobilized on the transducer surface. In the presence of the surface TYR biomarker, the immobilized catechol is rapidly converted to benzoquinone that is detected amperometrically, with a current signal proportional to the TYR level. The flexible epidermal bandage sensor relies on printing stress-enduring inks which display good resiliency against mechanical deformations, whereas the hollow microneedle device is filled with catechol-coated carbon paste for assessing tissue TYR levels. The bandage sensor can thus be used directly on the skin whereas microneedle device can reach melanoma tissues under the skin. Both wearable sensors are interfaced to an ultralight flexible electronic board, which transmits data wirelessly to a mobile device. The analytical performance of the resulting bandage and microneedle sensing systems are evaluated using TYR-containing agarose phantom gel and porcine skin. The new integrated conformal portable sensing platforms hold considerable promise for decentralized melanoma screening, and can be extended to the screening of other key biomarkers in skin moles.
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•An electrochemical sensor was designed for N€(Carboxymethyl)lysine detection via DPV.•The sensor retains its electrochemical proprieties upon high mechanical deformations.•Great ...outcomes were obtained in presence of intrinsic and extrinsic interferences.•Raw human saliva was successfully employed in this study.•The sensor features high repeatability and lifetime storage.
Advanced glycated end markers are involved in oxidative stress by producing long-term damage to proteins in ageing processes, atherosclerosis, and diabetes. The present work describes a cavitas printed electrochemical sensor for the direct salivary detection of N€(Carboxymethyl)lysine, a major advanced glycated end compound. The highly flexible and bendable sensor is integrated on a customized mouthguard placed on a phantom jaw that imitated the structure of the human oral cavity. The disposable sensor is readily attached on the mouthguard before usage and detached after the electrochemical investigation. Thus, it can be replaced whenever required. The sensor exhibits high selectivity and sensitivity in the phosphate buffer with a limit of detection of 166 ng/ml (equivalent to 0.81 μM) (over a range of 0.5–2500 μg/ml (equivalent to 2.45 μM–12.24 mM) N€(Carboxymethyl)lysine by employing a differential pulse voltammetry analytical procedure. Moreover, the cavitas sensor was tested in raw, untreated human saliva, and promising recoveries were obtained. The cost advantages of the printing technique, short timescale of the measurements, long storage stability and ease of use are attractive properties of the new mouthguard sensor. This non-invasive oral sensor for salivary N€(Carboxymethyl)lysine monitoring could potentially provide useful real-time information regarding a wearer's health condition, and thus, it holds considerable promise for the improved management of chronic diseases.
Early screening of clinically relevant pathogens in the environment is a highly desirable goal in clinical care, providing precious information that will improve patient-care outcomes. In this work, ...a glove-based electrochemical sensor has been designed for point-of-use screening of Pseudomonas aeruginosa’s virulence factors. The methodology used for the elaboration of the fabric platform relied on printing the conductive inks on the index and middle fingers of the glove, with the goal of screening pyocyanin and pyoverdine targets. The analytical signatures of the analytes were recorded in about 4 min, via the rapid and selective square-wave-voltammetry technique. Finger-based sensors display good performance and discrimination between the targets and potential interferences, along with good reproducibility. The sensors featured linearity over the 0.01–0.1 μM range for pyocyanin and 5–50 μM range for pyoverdine, with sensitivities of 2.51 μA/μM for pyocyanin and 1.09 nA/μM for pyoverdine (R 2 = 0.990 and 0.995, respectively) and detection limits of 3.33 nM for pyocyanin and 1.66 μM for pyoverdine. Moreover, the sensors were tested in binary mixtures of analytes, with successful outcomes. In order to gain information from the surrounding environment, the active electronic areas of the printed fingers were coated with a conductive hydrogel matrix, and relevant target surfaces were “swiped for notification” of contaminants. The simple fabrication, low-cost, and reusability of the proposed glove are likely to underpin the progressive drive of wearable sensors toward decentralized environmental and healthcare applications.
This study demonstrates the first example of completely food-based edible electrochemical sensors. The new edible composite electrodes consist of food materials and supplements serving as the edible ...conductor, corn, and olive oils as edible binders, vegetables as biocatalysts, and food-based packing sleeves. These edible composite electrodes are systematically characterized for their attractive electrochemical properties, such as potential window, capacitance, redox activity using various electrochemical techniques. The sensing performance of the edible carbon composite electrodes compares favorably with that of "traditional" carbon paste electrodes. Well defined voltammetric detection of catechol, uric acid, ascorbic acid, dopamine, and acetaminophen is demonstrated, including sensitive measurements in simulated saliva, gastric fluid, and intestinal fluid. Furthermore, successful biosensing applications are realized by incorporating a mushroom and horseradish vegetable tissues with edible carbon pastes for imparting biocatalytic activity toward the biosensing of phenolic and peroxide compounds. The attractive sensing performance of the new edible sensors indicates considerable promise for physiological monitoring applications and for developing edible and ingestible devices for diverse biomedical applications.
A novel magnetoimmunosensor, designed for sensitive and selective quantification of interleukin 6, is herein reported. The experimental design involves the covalent immobilization of anti‐interleukin ...6 antibody through an amidic bond formed with the carboxyl functionalities provided at the surface of protein G‐functionalized magnetic microparticles, assuring a sandwich‐type immunoassay with electrochemical label free detection. All the experimental parameters involved in the elaboration and testing protocol were optimized. A linear calibration plot between the charge transfer resistance and the logarithmic concentration of interleukin‐6 was achieved in the 1 pg mL−1 to 1 μg mL−1 range. A limit of quantification of 1 pg mL−1 and a detection limit of 0.3 pg mL−1 were obtained. The optimized magnetoimmunosensor showed an excellent selectivity against some potentially interfering proteins and has been successfully applied for the determination of target protein in human serum, proving its clinical relevance.
The development of robotic sensors that mimic the human sensing capabilities is critical for the interaction and cognitive abilities of modern robots. Though robotic skin with embedded pressure or ...temperature sensors has received recent attention, robotic chemical sensors have long been unnoticed due to the challenges associated with realizing chemical sensing modalities on robotic platforms. For realizing such chemically sensitive robotic skin, we exploit here the recent advances in wearable chemical sensor technology and flexible electronics, and describe chemical sensing robotic fingers for rapid screening of food flavors and additives. The stretchable taste-sensing finger electrochemical devices are printed on the robotic glove, which simulates the soft skin, and are integrated with a wireless electronic board for real-time data transmission. The printed middle, index, and ring robotic fingers allow accurate discrimination between sweetness, sourness, and spiciness, via direct electrochemical detection of glucose, ascorbic acid, and capsaicin. The sweet-sensing ability has been coupled with a caffeine-sensing robotic finger for rapid screening of the presence of sugar and caffeine in common beverages. The “sense of taste” chemically sensitive robotic technology thus enables accurate discrimination between different flavors, as was illustrated in numerous tests involving a wide range of liquid and solid food samples. Such realization of advanced wearable taste-sensing systems at the robot fingertips should pave the way to automated chemical sensing machinery, facilitating robotic decision for practical food assistance applications, with broad implications to a wide range of robotic sensing applications.
Bioelectrochemistry for miRNA detection Ciui, Bianca; Jambrec, Daliborka; Sandulescu, Robert ...
Current opinion in electrochemistry,
October 2017, 2017-10-00, Letnik:
5, Številka:
1
Journal Article
Recenzirano
•MiRNA genesis represents the key in understanding their implications in pathologies.•The number of miRNA molecules involved in divergent disorders is increasing annually.•Conventional methods have ...limitations, designing trustable tools for miRNA detection is needed.•Amplification strategies in the design of miRNA electrochemical assays are indisputable.•The shift toward POC devices is necessary for clinical investigation that involves miRNA.
Anomalous expression of miRNAs has been linked with cell cycles such as cell proliferation, stress response, differentiation, cell apoptosis and inflammation, which present a manifestation of multitude types of disorders and malignancies. For this reason, miRNAs became a class of biomarkers that is in the research focus in recent years. Their detection in an early stage of diseases represents a difficult challenge for analytical chemists who need to design not only specific but also highly sensitive tools for their detection. The progress achieved in the bio-electrochemical detection of miRNAs in the last 2 years is highlighted and commented, focusing on the applicability of developed strategies for point-of-care sensing.
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An electrochemical MIP–based sensor has been developed for the sensitive and selective detection of dopamine which plays the role of the template, being a biomarker with implication in numerous ...neurological diseases. The electrochemical and morphological characterization of the sensor was performed by microscopy, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV).
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