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Ali AMBH, Rageh AH, Abdel-aal FA, Mohamed AMI. Anatase titanium oxide nanoparticles and multi-walled carbon nanotubes-modified carbon paste electrode for simultaneous determination of avanafil and doxorubicin in plasma samples. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Monitoring of microbial cell viability using nanostructured electrodes modified with Graphene/Alumina nanocomposite. Biosens Bioelectron 2017; 91:857-862. [PMID: 28160653 DOI: 10.1016/j.bios.2017.01.060] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/22/2017] [Accepted: 01/25/2017] [Indexed: 01/24/2023]
Abstract
Microbial infections are rapidly increasing; however most of the existing microbiological and molecular detection methods are time consuming and/or cannot differentiate between the viable and dead cells which may overestimate the risk of infections. Therefore, a bioelectrochemical sensing platform with a high potential to the microbial-electrode interactions was designed based on decorated graphene oxide (GO) sheet with alumina (Al2O3) nanocrystals. GO-Al2O3 nanocomposite was synthesized using self-assembly of GO and Al2O3 and characterized using the scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), Raman-spectroscopy, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Enhancement of electrocatalytic activity of the composite-modified electrode was demonstrated. Thus, using the GO-Al2O3 nanocomposite modified electrode, the cell viability was determined by monitoring the bioelectrochemical response of the living microbial cells (bacteria and yeast) upon stimulation with carbon source. The bioelectrochemical assay was optimized to obtain high sensitivity and the method was applied to monitor cell viability and screen susceptibility of metabolically active cells (E. coli, B. subtilis, Enterococcus, P. aeruginosa and Salmonella typhi) to antibiotics such as ampicillin and kanamycin. Therefore, the developed assay is suitable for cell proliferation and cytotoxicity testing.
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Mediated bioelectrochemical system for biosensing the cell viability of Staphylococcus aureus. Anal Bioanal Chem 2015; 408:579-87. [PMID: 26522330 DOI: 10.1007/s00216-015-9134-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 09/13/2015] [Accepted: 10/19/2015] [Indexed: 01/21/2023]
Abstract
Staphylococcus aureus is one of the most dangerous human pathogens and is the cause of numerous illnesses ranging from moderate skin infections to life-threatening diseases. Despite advances made in identifying microorganisms, rapid detection methods for the viability of bacteria are still missing. Here, we report a rapid electrochemical assay for cell viability combining the use of double redox mediators and multiwall carbon nanotubes-screen printed electrodes (MWCNTs-SPE), ferricyanide (FCN) and 2,6-dichlorophenolindophenol (DCIP), which served as electron shuttle to enable the bacterial-electrode communications. The current originating from the metabolically active cells was recorded for probing the activity of the intracellular redox centers. Blocking of the respiratory chain pathways with electron transfer inhibitors demonstrated the involvement of the electron transport chain in the reaction. A good correlation between the number of the metabolically active cells and the current was obtained. The proposed assay has been exploited for monitoring cell proliferation of S. aureus during the growth. The sensitivity of the detection method reached 0.1 OD600. Therefore, the technique described is promising for estimating the cell number, measuring the cell viability, and probing intracellular redox center(s).
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Georgescu R, van Staden JF, Stefan-van Staden RI, Boscornea C. Evaluation of amperometric dot microsensors for the analysis of folic acid in pharmaceutical tablets and urine samples. J PORPHYR PHTHALOCYA 2015. [DOI: 10.1142/s1088424615500066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Nineteen amperometric dot microsensors based on graphite and graphene modified with a selection of porphyrins and phthalocyanines were evaluated and tested for their ability of the analysis of folic acid in pharmaceutical tablets (e.g. Acifol) and biological samples (e.g. urine), using differential pulse voltammetry. Cyclic voltammetry was used to optimize the working conditions, e.g. pH and electrolyte for the proposed amperometric dot microsensors. The optimum working pH was 7.0 (phosphate buffer), with a 0.1 M potassium chloride supporting electrolyte. The linear concentration ranges for folic acid were between 10-6 and 10-3) M for all dot microsensors except dot microsensors based on graphite modified with tetraamino cobalt(II) phthalocyanine and tetranitro manganese(II) phthalocyanine which had linear concentration ranges between 10-6 and 10-4 M . The highest sensitivity (0.770 nA. mmolL-1) was recorded for the graphite modified with tetraamino cobalt(II) phthalocyanine based dot sensor and the lowest limit of detection (1.14 10-7 M ) for the graphite modified with tetranitro zinc(II) phthalocyanine based dot sensor. The dot sensors were used for the reliable analysis of folic acid in Acifol tablets and urine samples, with recoveries higher than 94.00% and 99.00%, respectively.
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Affiliation(s)
- Ramona Georgescu
- Laboratory of Electrochemistry and PATLAB Bucharest, National Institute of Research for Electrochemistry, and Condensed Matter, Bucharest 060021, Romania
- Department of Bioresources and Polymer Science, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Romania
| | - Jacobus Frederick van Staden
- Laboratory of Electrochemistry and PATLAB Bucharest, National Institute of Research for Electrochemistry, and Condensed Matter, Bucharest 060021, Romania
| | - Raluca-Ioana Stefan-van Staden
- Laboratory of Electrochemistry and PATLAB Bucharest, National Institute of Research for Electrochemistry, and Condensed Matter, Bucharest 060021, Romania
| | - Cristian Boscornea
- Department of Bioresources and Polymer Science, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Romania
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Dwivedi S, Wahab R, Khan F, Mishra YK, Musarrat J, Al-Khedhairy AA. Reactive oxygen species mediated bacterial biofilm inhibition via zinc oxide nanoparticles and their statistical determination. PLoS One 2014; 9:e111289. [PMID: 25402188 PMCID: PMC4234364 DOI: 10.1371/journal.pone.0111289] [Citation(s) in RCA: 199] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/29/2014] [Indexed: 02/03/2023] Open
Abstract
The formation of bacterial biofilm is a major challenge in clinical applications. The main aim of this study is to describe the synthesis, characterization and biocidal potential of zinc oxide nanoparticles (NPs) against bacterial strain Pseudomonas aeruginosa. These nanoparticles were synthesized via soft chemical solution process in a very short time and their structural properties have been investigated in detail by using X-ray diffraction and transmission electron microscopy measurements. In this work, the potential of synthesized ZnO-NPs (∼10–15 nm) has been assessed in-vitro inhibition of bacteria and the formation of their biofilms was observed using the tissue culture plate assays. The crystal violet staining on biofilm formation and its optical density revealed the effect on biofilm inhibition. The NPs at a concentration of 100 µg/mL significantly inhibited the growth of bacteria and biofilm formation. The biofilm inhibition by ZnO-NPs was also confirmed via bio-transmission electron microscopy (Bio-TEM). The Bio-TEM analysis of ZnO-NPs treated bacteria confirmed the deformation and damage of cells. The bacterial growth in presence of NPs concluded the bactericidal ability of NPs in a concentration dependent manner. It has been speculated that the antibacterial activity of NPs as a surface coating material, could be a feasible approach for controlling the pathogens. Additionally, the obtained bacterial solution data is also in agreement with the results from statistical analytical methods.
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Affiliation(s)
- Sourabh Dwivedi
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Rizwan Wahab
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
- * E-mail:
| | - Farheen Khan
- Department of Chemistry, Aligarh Muslim University, Aligarh, India
| | - Yogendra K. Mishra
- Functional Nanomaterials, Institute for Materials Science, University of Kiel, Kiel, Germany
| | - Javed Musarrat
- Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, India
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Burmeister JJ, Davis VA, Quintero JE, Pomerleau F, Huettl P, Gerhardt GA. Glutaraldehyde cross-linked glutamate oxidase coated microelectrode arrays: selectivity and resting levels of glutamate in the CNS. ACS Chem Neurosci 2013; 4:721-8. [PMID: 23650904 DOI: 10.1021/cn4000555] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Glutaraldehyde is widely used as a cross-linking agent for enzyme immobilization onto microelectrodes. Recent studies and prior reports indicate changes in enzyme activity and selectivity with certain glutaraldehyde cross-linking procedures that may jeopardize the performance of microelectrode recordings and lead to falsely elevated responses in biological systems. In this study, the sensitivity of glutaraldehyde cross-linked glutamate oxidase-based microelectrode arrays to 22 amino acids was tested and compared to glutamate. As expected, responses to electroactive amino acids (Cys, Tyr, Trp) were detected at both nonenzyme-coated and enzyme-coated microelectrodes sites, while the remaining amino acids yielded no detectable responses. Electroactive amino acids were effectively blocked with a m-phenylene diamine (mPD) layer and, subsequently, no responses were detected. Preliminary results on the use of poly(ethylene glycol) diglycidyl ether (PEGDE) as a potentially more reliable cross-linking agent for the immobilization of glutamate oxidase onto ceramic-based microelectrode arrays are reported and show no significant advantages over glutaraldehyde as we observe comparable selectivities and responses. These results support that glutaraldehyde-cross-linked glutamate oxidase retains sufficient enzyme specificity for accurate in vivo brain measures of tonic and phasic glutamate levels when immobilized using specific "wet" coating procedures.
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Affiliation(s)
- Jason J. Burmeister
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Verda A. Davis
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Jorge E. Quintero
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Francois Pomerleau
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Peter Huettl
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Greg A. Gerhardt
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
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Beitollah H, Goodarzian M, Khalilzadeh MA, Karimi-Maleh H, Hassanzadeh M, Tajbakhsh M. Electrochemical behaviors and determination of carbidopa on carbon nanotubes ionic liquid paste electrode. J Mol Liq 2012. [DOI: 10.1016/j.molliq.2012.06.026] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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