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(searched for: doi:10.3390/bios7010013)
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, Francesca Meloni, , Adam Szyszka, , ,
Published: 5 September 2022
Journal: RSC Advances
RSC Advances, Volume 12, pp 25342-25353; https://doi.org/10.1039/d2ra04045j

Abstract:
The main goal of the presented study was to design a biosensor-based system for epinephrine (EP) detection using a poly-thiophene derivative and tyrosinase as a biorecognition element. We compared two different electroanalytical techniques to select the most prominent technique for analyzing the neurotransmitter. The prepared biosensor system exhibited good parameters; the differential pulse (DPV) technique presented a wide linear range (1–20 μM and 30–200 μM), with a low detection limit (0.18 nM and 1.03 nM). In the case of chronoamperometry (CA), a high signal-to-noise ratio and lower reproducibility were observed, causing a less broad linear range (10–200 μM) and a higher detection limit (125 nM). Therefore, the DPV technique was used for the calculation of sensitivity (0.0011 μA mM−1 cm−2), stability (49 days), and total surface coverage (4.18 × 10−12 mol cm−2). The biosensor also showed very high selectivity in the presence of common interfering species (i.e. ascorbic acid, uric acid, norepinephrine, dopamine) and was successfully applied for EP determination in a pharmaceutical sample.
Fares Zouaoui, Nadia Zine, Abdelhamid Errachid,
Published: 30 November 2021
Journal: Electroanalysis
Electroanalysis, Volume 34, pp 1131-1140; https://doi.org/10.1002/elan.202100610

The publisher has not yet granted permission to display this abstract.
Published: 20 November 2021
by MDPI
Journal: Membranes
Abstract:
There is growing interest for bioanalytical tools that might be designed for a specific user, primarily for research purposes. In this perspective, a new, highly stable potentiometric sensor based on glassy carbon/polyazulene/NH4+-selective membrane was developed and utilized for urease activity determination. Urease–urea interaction studies were carried out and the Michaelis–Menten constant was established for this enzymatic reaction. Biofunctionalization of the ammonium ion-selective sensor with urease lead to urea biosensor with remarkably good potential stability (drift coefficient ~0.9 mV/h) and short response time (t95% = 36 s). The prepared biosensor showed the Nernstian response (S = 52.4 ± 0.7 mV/dec) in the urea concentration range from 0.01 to 20 mM, stable for the experimental time of 60 days. In addition, some insights into electrical properties of the ion-to-electron transducing layer resulting from impedance spectroscopy measurements are presented. Based on the RCQ equivalent circuits comparison, it can be drawn that the polyazulene (PAz) layer shows the least capacitive behavior, which might result in good time stability of the sensor in respect to response as well as potential E0. Both the polyazulene-based solid-contact ion selective electrodes and urea biosensors were successfully used in trial studies for determination of ammonium ion and urea in human saliva samples. The accuracy of ammonium ion and urea levels determination by potentiometric method was confirmed by two reference spectrophotometric methods.
, , Ömer Isildak, Ibrahim Isildak
Clinica Chimica Acta; International Journal of Clinical Chemistry, Volume 524, pp 154-163; https://doi.org/10.1016/j.cca.2021.11.011

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, Minakshi Sharma, Geeta Singh
IET nanobiotechnology, Volume 15, pp 358-379; https://doi.org/10.1049/nbt2.12050

Abstract:
The quick progress in health care technology as a recurrent measurement of biochemical factors such as blood components leads to advance development and growth in biosensor technology necessary for effectual patient concern. The review wok of authors present a concise information and brief discussion on the development made in the progress of potentiometric, field effect transistor, graphene, electrochemical, optical, polymeric, nanoparticles and nanocomposites based urea biosensors in the past two decades. The work of authors is also centred on different procedures/methods for detection of urea by using amperometric, potentiometric, conductometric and optical processes, where graphene, polymer etc. are utilised as an immobilised material for the fabrication of biosensors. Further, a comparative revision has been accomplished on various procedures of urea analysis using different materials-based biosensors, and it discloses that electrochemical and potentiometric biosensor is the most promise one among all, in terms of rapid response time, extensive shelf life and resourceful design.
, Dhammajyot K. Gaikwad, Nitin B. Girhe, Hanuman N. Thorat, Pravina P. Pawar
Published: 13 April 2021
Biotechnology and applied biochemistry; https://doi.org/10.1002/bab.2168

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Published: 1 January 2021
The publisher has not yet granted permission to display this abstract.
Baha Öndeş, Fatma Akpınar, Murat Uygun, Mihrican Muti,
Published: 26 October 2020
Microchemical Journal, Volume 160; https://doi.org/10.1016/j.microc.2020.105667

The publisher has not yet granted permission to display this abstract.
Rebeca Da Rocha Rodrigues, Tamires Pedrali de Aquino, Luciano Caseli,
Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 603; https://doi.org/10.1016/j.colsurfa.2020.125139

The publisher has not yet granted permission to display this abstract.
Sook H. Park, Yi Zhang, John A. Rogers, Lorenzo Gallon
Current opinion in nephrology and hypertension, Volume 28, pp 390-396; https://doi.org/10.1097/mnh.0000000000000517

Abstract:
Hypertension (HTN) and chronic kidney disease (CKD) are significant problems. With recent advances in technologies, biosensors have shown a great potential to provide better home monitoring in hypertension (HTN), medication compliance, diagnostic device for kidney disease, CKD/end-stage renal disease (ESRD) care, and post kidney transplant management. Multiple devices/biosensors have been developed related to HTN, kidney function including real-time glomerular filtration rate, CKD/end-stage renal disease, and transplant care. In recent advances in wearable biosensors, point of care monitoring system could provide more integrated care to the patients via telenephrology. This review focuses on the recent advances in biosensors which may be useful for HTN and nephrology. We will discuss future potential clinical implication of these biosensors.
B.S. Dakshayini, , Amit Mishra, , Shweta J. Malode, , S. Naveen, Anjanapura V. Raghu
Published: 1 March 2019
Microchemical Journal, Volume 147, pp 7-24; https://doi.org/10.1016/j.microc.2019.02.061

The publisher has not yet granted permission to display this abstract.
Published: 28 November 2018
Colloids and Surfaces B: Biointerfaces, Volume 175, pp 1-9; https://doi.org/10.1016/j.colsurfb.2018.11.076

Abstract:
One of the most important factors for the proper functioning of enzymatic electrochemical biosensors is the enzyme immobilization strategy. In this work, glucose oxidase was covalently immobilized using pentafluorophenyl methacrylate (PFM) by applying two different surface modification techniques (plasma polymerization and plasma-grafting). The grafted surface was specifically designed to covalently anchor enzyme molecules. It was observed using QCM-D measurements the PFM plasma-grafted surfaces were able to retain a higher number of active enzyme molecules than the PFM polymerized surfaces. An amperometric glucose biosensor using titanium dioxide nanotubes array (TiO2NTAs) modified by PFM plasma-grafted surface was prepared. The resulting biosensor exhibited a fast response and short analysis time (approximately eight minutes per sample). Moreover, this biosensor achieved high sensitivity (9.76 μA·mM-1) with a linear range from 0.25 to 1.49 mM and a limit of detection (LOD) equal to 0.10 mM of glucose. In addition, the glucose content of 16 different food samples was successfully measured using the developed biosensor. The obtained results were compared with the respective HPLC value and a deviation smaller than 10% was obtained in all the cases. Therefore, the biosensor was able to overcome all possible interferences in the selected samples/matrices.
, , , Timbangen Sembiring
Published: 1 November 2018
Journal of Physics: Conference Series, Volume 1120; https://doi.org/10.1088/1742-6596/1120/1/012024

Abstract:
Potentiometric sensors provide an opportunity to perform biomedical, environmental analysis, and industry analysis, these sensors are generally easy to use, portable, simple, and inexpensive. The potentiometric method is a method of measuring the potential difference of the balance between the indicator electrode and the reference electrode. Chemical sensors are a device that can convert chemical quantities into electrical quantities. Chemical sensors sensitive to one analyte involve a combination of molecular recognition elements PVA-enzyme PVC-KTpClPB and transducer to detect an analytical bond through a voltage signal. The urease enzyme is used for the determination of urea, the urea sensor means an accurate determination of urea essential with respect to renal function and biomedical applications. ISE is a good approach to build chemical sensors in detecting urea analyte. The immobilized product as a molecular recognition element of PVC-enzyme PVC-KTpClPB has a sensitivity of 19,069 mV/decade R2 = 0.94 with a range of 1.10-5 - 5.10-4 M in electrolyte solution consisting of buffer KH2PO4 0.001 M and KCl 0.001 M.
Published: 21 May 2018
by MDPI
Journal: Polymers
Abstract:
Over the past decades, biosensors, a class of physicochemical detectors sensitive to biological analytes, have drawn increasing interest, particularly in light of growing concerns about human health. Functional polymeric materials have been widely researched for sensing applications because of their structural versatility and significant progress that has been made concerning their chemistry, as well as in the field of nanotechnology. Polymeric nanoparticles are conventionally used in sensing applications due to large surface area, which allows rapid and sensitive detection. On the macroscale, hydrogels are crucial materials for biosensing applications, being used in many wearable or implantable devices as a biocompatible platform. The performance of both hydrogels and nanoparticles, including sensitivity, response time, or reversibility, can be significantly altered and optimized by changing their chemical structures; this has encouraged us to overview and classify chemical design strategies. Here, we have organized this review into two main sections concerning the use of nanoparticles and hydrogels (as polymeric structures) for biosensors and described chemical approaches in relevant subcategories, which act as a guide for general synthetic strategies.
Seema Jakhar,
Published: 1 February 2018
Biosensors and Bioelectronics, Volume 100, pp 242-250; https://doi.org/10.1016/j.bios.2017.09.005

Abstract:
The nanoparticles (NPs) aggregates of commercial urease from jack beans (Canavalia ensiformis) were prepared by desolvation and glutaraldehyde crosslinking and functionalized by cysteamine dihydrochloride. These enzyme nanoparticles (ENPs) were characterized by transmission electron microscopy (TEM), UV and Fourier transform infrared (FTIR) spectroscopy. The TEM images of urease NPs showed their size in the range, 18-100nm with an average of 51.2nm. The ENPs were more active and stable with a longer shelf life than native enzyme molecules. The ENPs were immobilized onto chitosan (CHIT) activated nitrocellulose (NC) membrane via glutaraldehyde coupling with 32.22% retention of initial activity of free ureaseNPs with a conjugation yield of 1.63mg/cm. This NC membrane was mounted at the lower/sensitive end of the ammonium ion selective electrode (AISE) with O-ring and then electrode was connected to a digital pH meter to construct a potentiometric urea biosensor. The biosensor exhibited optimum response within 10s at pH 5.5and 40°C. The biosensor was employed for measurement of potentiometric determination of urea in sera of apparently healthy and persons suffering from kidney disorders. The biosensor displayed a low detection limit of 1µM/L with a wide working range of 2-80µM/L (0.002-0.08mM) and sensitivity of 23mV/decade. The analytical recovery of added urea in serum was 106.33%. The within and between-batch coefficient of variations (CVs) of present biosensor were 0.18% and 0.32% respectively. There was a good correlation (r = 0.99) between sera urea values obtained by reference method (Enzymic colorimetric kit method) and the present biosensor. The biosensor had negligible interference from Na,K,NH and Ca but Mg,Cu and ascorbic acid but had slight interference, which was overcome by specific ion selective electrode. The ENPs bound NC membrane was used maximally 8-9 times per day over a period of 180 days, when stored in 0.01M sodium acetate buffer pH 5.5 at 4°C.
, Amira M. Kamel, Mona S. Hashem, Hassan N. A. Hassan, Mahmoud A. Abd El-Ghaffar
Published: 23 January 2018
Journal of Solid State Electrochemistry, Volume 22, pp 1817-1823; https://doi.org/10.1007/s10008-017-3857-z

The publisher has not yet granted permission to display this abstract.
Avinash Kumar Pandey, Prem Chandra Pandey, ,
Published: 8 September 2017
Journal of Applied Polymer Science, Volume 135; https://doi.org/10.1002/app.45705

The publisher has not yet granted permission to display this abstract.
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