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Rotem S, Steinberger-Levy I, Israeli O, Zahavy E, Aloni-Grinstein R. Beating the Bio-Terror Threat with Rapid Antimicrobial Susceptibility Testing. Microorganisms 2021; 9:1535. [PMID: 34361970 PMCID: PMC8304332 DOI: 10.3390/microorganisms9071535] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 11/16/2022] Open
Abstract
A bioterror event using an infectious bacterium may lead to catastrophic outcomes involving morbidity and mortality as well as social and psychological stress. Moreover, a bioterror event using an antibiotic resistance engineered bacterial agent may raise additional concerns. Thus, preparedness is essential to preclude and control the dissemination of the bacterial agent as well as to appropriately and promptly treat potentially exposed individuals or patients. Rates of morbidity, death, and social anxiety can be drastically reduced if the rapid delivery of antimicrobial agents for post-exposure prophylaxis and treatment is initiated as soon as possible. Availability of rapid antibiotic susceptibility tests that may provide key recommendations to targeted antibiotic treatment is mandatory, yet, such tests are only at the development stage. In this review, we describe the recently published rapid antibiotic susceptibility tests implemented on bioterror bacterial agents and discuss their assimilation in clinical and environmental samples.
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Affiliation(s)
| | | | | | | | - Ronit Aloni-Grinstein
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 74100, Israel; (S.R.); (I.S.-L.); (O.I.); (E.Z.)
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Bellali S, Lagier JC, Raoult D, Bou Khalil J. Among Live and Dead Bacteria, the Optimization of Sample Collection and Processing Remains Essential in Recovering Gut Microbiota Components. Front Microbiol 2019; 10:1606. [PMID: 31354688 PMCID: PMC6635563 DOI: 10.3389/fmicb.2019.01606] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/26/2019] [Indexed: 12/12/2022] Open
Abstract
The human gut microbiota plays an important role in human health. Accessing and culturing the gut microbes remains critical in microbiology. The culturomics approach, combined with sequencing strategies, provides new insights in the study of gut microbiota components. However, we are still far from having described all the microbes. Many factors are involved in recovering as much bacteria as possible. One of the most important factors is sample preparation and conservation. The aim of the present work was to evaluate three different types of stool sample conditioning by mainly studying the effect of atmospheric oxygen on bacterial viability and culturability. Quantitative analysis of fecal samples from eight different healthy individuals was carried out using a culture-independent method (flow cytometry) and a culture-dependent method (plating technique). We found that the cultured bacteria reached a 50% yield when the samples were exposed to oxygen for 120 min without any protectant medium, while the percentage of culturability increased to 67% in the presence of antioxidants. More importantly, when samples were exposed to oxygen for less than 2 min, combined with the work under the anaerobic chamber, no discordance was found between the two counting techniques and the culturability increased to 87%. Our study confirmed the importance of sample conditioning to preserve the bacterial viability in samples, especially for oxygen-sensitive intestinal bacteria.
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Affiliation(s)
- Sara Bellali
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, Marseille, France
| | - Jean-Christophe Lagier
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, Marseille, France
| | - Didier Raoult
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, Marseille, France
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Shifman O, Steinberger-Levy I, Aloni-Grinstein R, Gur D, Aftalion M, Ron I, Mamroud E, Ber R, Rotem S. A Rapid Antimicrobial Susceptibility Test for Determining Yersinia pestis Susceptibility to Doxycycline by RT-PCR Quantification of RNA Markers. Front Microbiol 2019; 10:754. [PMID: 31040834 PMCID: PMC6477067 DOI: 10.3389/fmicb.2019.00754] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 03/26/2019] [Indexed: 12/30/2022] Open
Abstract
Great efforts are being made to develop new rapid antibiotic susceptibility tests to meet the demand for clinical relevance versus disease progression. This is important especially in diseases caused by bacteria such as Yersinia pestis, the causative agent of plague, which grows rapidly in vivo but relatively slow in vitro. This compromises the ability to use standard growth-based susceptibility tests to obtain rapid and proper antibiotic treatment guidance. Using our previously described platform of quantifying antibiotic-specific transcriptional changes, we developed a molecular test based on changes in expression levels of doxycycline response-dependent marker genes that we identified by transcriptomic analysis. This enabled us to determine the minimal inhibitory concentration of doxycycline within 7 h compared to the 24 h required by the standard CLSI test. This assay was validated with various Y. pestis strains. Moreover, we demonstrated the applicability of the molecular test, combined with a new rapid bacterial isolation step from blood cultures, and show its relevance as a rapid test in clinical settings.
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Affiliation(s)
- Ohad Shifman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Ida Steinberger-Levy
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Ronit Aloni-Grinstein
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - David Gur
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Moshe Aftalion
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Izhar Ron
- Department of Physical Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Emanuelle Mamroud
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Raphael Ber
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Shahar Rotem
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
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Walper SA, Lasarte Aragonés G, Sapsford KE, Brown CW, Rowland CE, Breger JC, Medintz IL. Detecting Biothreat Agents: From Current Diagnostics to Developing Sensor Technologies. ACS Sens 2018; 3:1894-2024. [PMID: 30080029 DOI: 10.1021/acssensors.8b00420] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Although a fundamental understanding of the pathogenicity of most biothreat agents has been elucidated and available treatments have increased substantially over the past decades, they still represent a significant public health threat in this age of (bio)terrorism, indiscriminate warfare, pollution, climate change, unchecked population growth, and globalization. The key step to almost all prevention, protection, prophylaxis, post-exposure treatment, and mitigation of any bioagent is early detection. Here, we review available methods for detecting bioagents including pathogenic bacteria and viruses along with their toxins. An introduction placing this subject in the historical context of previous naturally occurring outbreaks and efforts to weaponize selected agents is first provided along with definitions and relevant considerations. An overview of the detection technologies that find use in this endeavor along with how they provide data or transduce signal within a sensing configuration follows. Current "gold" standards for biothreat detection/diagnostics along with a listing of relevant FDA approved in vitro diagnostic devices is then discussed to provide an overview of the current state of the art. Given the 2014 outbreak of Ebola virus in Western Africa and the recent 2016 spread of Zika virus in the Americas, discussion of what constitutes a public health emergency and how new in vitro diagnostic devices are authorized for emergency use in the U.S. are also included. The majority of the Review is then subdivided around the sensing of bacterial, viral, and toxin biothreats with each including an overview of the major agents in that class, a detailed cross-section of different sensing methods in development based on assay format or analytical technique, and some discussion of related microfluidic lab-on-a-chip/point-of-care devices. Finally, an outlook is given on how this field will develop from the perspective of the biosensing technology itself and the new emerging threats they may face.
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Affiliation(s)
- Scott A. Walper
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Guillermo Lasarte Aragonés
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
- College of Science, George Mason University Fairfax, Virginia 22030, United States
| | - Kim E. Sapsford
- OMPT/CDRH/OIR/DMD Bacterial Respiratory and Medical Countermeasures Branch, U.S. Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Carl W. Brown
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
- College of Science, George Mason University Fairfax, Virginia 22030, United States
| | - Clare E. Rowland
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
- National Research Council, Washington, D.C. 20036, United States
| | - Joyce C. Breger
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Igor L. Medintz
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
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Rodriguez AFR, Rocha CO, Piazza RD, Dos Santos CC, Morales MA, Faria FSEDV, Iqbal MZ, Barbosa L, Chaves YO, Mariuba LA, Jafelicci M, Marques RFC. Synthesis, characterization and applications of maghemite beads functionalized with rabbit antibodies. NANOTECHNOLOGY 2018; 29:365701. [PMID: 29894981 DOI: 10.1088/1361-6528/aacc21] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Magnetic nanoparticles (NPs) have attracted great attention owing to their applications in the biomedical field. In the present work, maghemite (γFe2O3) NPs of 6.5 nm were prepared using a sonochemical method and used to prepare magnetic beads through silanization with 3-aminopropyltrimethoxysilane (APTS). Subsequently, amino groups in the resulting APTS-γFe2O3 beads were converted to carboxylic acid (CARB-γFe2O3) through the succinic anhydride reaction, as confirmed by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy and dynamic light scattering (DLS) measurements. The size of these beads was measured as 12 nm and their hydrodynamic diameter as 490 nm, using TEM analysis and DLS, respectively. The CARB-γFe2O3 beads were further functionalized by immobilizing rabbit antibodies on their surfaces; the immobilization was confirmed by flow cytometry and ionic strength. The samples were further characterized by Mössbauer spectroscopy and DC magnetization measurements. Studies on magnetic relaxivities showed that magnetic beads present great potential for application in MR imaging.
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Affiliation(s)
- A F R Rodriguez
- Federal University of Acre, Laboratory of Nanobiotechnology, Rio Branco, 69920-900, AC, Brazil
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Rapid Antibiotic Susceptibility Determination for Yersinia pestis Using Flow Cytometry Spectral Intensity Ratio (SIR) Fluorescence Analysis. J Fluoresc 2018; 28:1151-1161. [PMID: 30117073 PMCID: PMC6153737 DOI: 10.1007/s10895-018-2279-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Accepted: 08/09/2018] [Indexed: 12/25/2022]
Abstract
Rapid antimicrobial susceptibility tests (ASTs) are essential tool for proper treatment of patients infected by Yersinia pestis (Y. pestis), the causative agent of plague, or for post-exposure prophylaxis of a population exposed to a naturally acquired or deliberately prepared resistant variant. The standard AST of Y. pestis is based on bacterial growth and requires 24–48 h of incubation in addition to the time required for prior isolation of a bacterial culture from the clinical or environmental sample, which may take an additional 24–48 h. In this study, we present a new and rapid AST method based on a fluorescence determination of the minimum inhibitory concentration (MIC). Our method includes the incubation of bacteria with an antibiotic, followed by staining of the bacteria with oxonol dye (SynaptoGreen C4/FM1–43), which enables the rapid detection of an antibiotic’s effect on bacterial viability. We show that stained, non-viable bacteria exhibit a spectral redshift and an increase in fluorescence intensity compared to intact control bacteria. Based on these criteria, we developed a rapid flow cytometer measurement procedure and a unique spectral intensity ratio (SIR) analysis that enables determination of antibiotic susceptibility for Y. pestis within 6 h instead of the 24 to 48 h required for the standard AST. This new rapid determination of antibiotic susceptibility could be crucial for reducing mortality and preventing the spread of disease.
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Mocan T, Matea CT, Pop T, Mosteanu O, Buzoianu AD, Puia C, Iancu C, Mocan L. Development of nanoparticle-based optical sensors for pathogenic bacterial detection. J Nanobiotechnology 2017; 15:25. [PMID: 28359284 PMCID: PMC5374694 DOI: 10.1186/s12951-017-0260-y] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 03/20/2017] [Indexed: 01/16/2023] Open
Abstract
Background Pathogenic bacteria contribute to various globally important diseases, killing millions of people each year. Various fields of medicine currently benefit from or may potentially benefit from the use of nanotechnology applications, in which there is growing interest. Disease-related biomarkers can be rapidly and directly detected by nanostructures, such as nanowires, nanotubes, nanoparticles, cantilevers, microarrays, and nanoarrays, as part of an accurate process characterized by lower sample consumption and considerably higher sensitivity. There is a need for accurate techniques for pathogenic bacteria identification and detection to allow the prevention and management of pathogenic diseases and to assure food safety. Conclusion The focus of this review is on the current nanoparticle-based techniques for pathogenic bacterial identification and detection using these applications.
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Affiliation(s)
- Teodora Mocan
- Department of Nanomedicine, "Octavian Fodor" Gastroenterology Institute, 19-21 Croitorilor Street, Cluj-Napoca, Romania.,Department of Physiology, "Iuliu Hatieganu" University of Medicine and Pharmacy, 3-5 Clinicilor Street, Cluj-Napoca, Romania
| | - Cristian T Matea
- Department of Nanomedicine, "Octavian Fodor" Gastroenterology Institute, 19-21 Croitorilor Street, Cluj-Napoca, Romania.,3rd Surgery Clinic, "Iuliu Hatieganu" University of Medicine and Pharmacy, 19-21 Croitorilor Street, Cluj-Napoca, Romania
| | - Teodora Pop
- 3rd Gastroenterology Department, "Iuliu Hatieganu" University of Medicine and Pharmacy, 19-21 Croitorilor Street, Cluj-Napoca, Romania
| | - Ofelia Mosteanu
- 3rd Gastroenterology Department, "Iuliu Hatieganu" University of Medicine and Pharmacy, 19-21 Croitorilor Street, Cluj-Napoca, Romania
| | - Anca Dana Buzoianu
- Department of Clinical Pharmacology, "Iuliu Hatieganu" University of Medicine and Pharmacy, 3-5 Clinicilor Street, Cluj-Napoca, Romania
| | - Cosmin Puia
- Department of Nanomedicine, "Octavian Fodor" Gastroenterology Institute, 19-21 Croitorilor Street, Cluj-Napoca, Romania.,3rd Surgery Clinic, "Iuliu Hatieganu" University of Medicine and Pharmacy, 19-21 Croitorilor Street, Cluj-Napoca, Romania
| | - Cornel Iancu
- Department of Nanomedicine, "Octavian Fodor" Gastroenterology Institute, 19-21 Croitorilor Street, Cluj-Napoca, Romania. .,3rd Surgery Clinic, "Iuliu Hatieganu" University of Medicine and Pharmacy, 19-21 Croitorilor Street, Cluj-Napoca, Romania.
| | - Lucian Mocan
- Department of Nanomedicine, "Octavian Fodor" Gastroenterology Institute, 19-21 Croitorilor Street, Cluj-Napoca, Romania. .,3rd Surgery Clinic, "Iuliu Hatieganu" University of Medicine and Pharmacy, 19-21 Croitorilor Street, Cluj-Napoca, Romania.
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Aloni-Grinstein R, Schuster O, Yitzhaki S, Aftalion M, Maoz S, Steinberger-Levy I, Ber R. Isolation of Francisella tularensis and Yersinia pestis from Blood Cultures by Plasma Purification and Immunomagnetic Separation Accelerates Antibiotic Susceptibility Determination. Front Microbiol 2017; 8:312. [PMID: 28293231 PMCID: PMC5329073 DOI: 10.3389/fmicb.2017.00312] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 02/15/2017] [Indexed: 01/16/2023] Open
Abstract
The early symptoms of tularemia and plague, which are caused by Francisella tularensis and Yersinia pestis infection, respectively, are common to other illnesses, resulting in a low index of suspicion among clinicians. Moreover, because these diseases can be treated only with antibiotics, rapid isolation of the bacteria and antibiotic susceptibility testing (AST) are preferable. Blood cultures of patients may serve as a source for bacteria isolation. However, due to the slow growth rates of F. tularensis and Y. pestis on solid media, isolation by plating blood culture samples on proper agar plates may require several days. Thus, improving the isolation procedure prior to antibiotic susceptibility determination is a major clinically relevant need. In this study, we developed a rapid, selective procedure for the isolation of F. tularensis and Y. pestis from blood cultures. We examined drop-plating and plasma purification followed by immunomagnetic separation (IMS) as alternative isolation methods. We determined that replacing the classical isolation method with drop-plating is advantageous with respect to time at the expense of specificity. Hence, we also examined isolation by IMS. Sub-localization of F. tularensis within blood cultures of infected mice has revealed that the majority of the bacteria are located within the extracellular fraction, in the plasma. Y. pestis also resides within the plasma. Therefore, the plasma fraction was isolated from blood cultures and subjected to an IMS procedure using polyclonal anti-F. tularensis live vaccine strain (LVS) or anti-Y. pestis antibodies conjugated to 50-nm nano-beads. The time required to reach an inoculum of sufficient bacteria for AST was shortest when using the plasma and IMSs for both bacteria, saving up to 2 days of incubation for F. tularensis and 1 day for Y. pestis. Our isolation procedure provides a proof of concept for the clinical relevance of rapid isolation for AST from F. tularensis- and Y. pestis-infected patients.
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Affiliation(s)
- Ronit Aloni-Grinstein
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Ofir Schuster
- Department of Infectious diseases, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Shmuel Yitzhaki
- Department of Infectious diseases, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Moshe Aftalion
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Sharon Maoz
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Ida Steinberger-Levy
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Raphael Ber
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
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Moro L, Turemis M, Marini B, Ippodrino R, Giardi MT. Better together: Strategies based on magnetic particles and quantum dots for improved biosensing. Biotechnol Adv 2017; 35:51-63. [DOI: 10.1016/j.biotechadv.2016.11.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 09/29/2016] [Accepted: 11/27/2016] [Indexed: 12/14/2022]
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Pan H, Zhang Y, He GX, Katagori N, Chen H. A comparison of conventional methods for the quantification of bacterial cells after exposure to metal oxide nanoparticles. BMC Microbiol 2014; 14:222. [PMID: 25138641 PMCID: PMC4236543 DOI: 10.1186/s12866-014-0222-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 08/13/2014] [Indexed: 12/18/2022] Open
Abstract
Background Due to potential interference of nanoparticles on bacterial quantification, there is a challenge to develop a fast, accurate and reproducible method for bacterial quantification. Currently various bacterial quantification methods are used by researchers performing nanoparticles study, but there has been no efficacy evaluation of these methods. Here we study interference of nanoparticles on three most commonly used conventional bacterial quantification methods, including colony counting to determine the colony-forming units (CFU), spectrophotometer method of optical density (OD) measurement, and flow cytometry (FCM). Results Three oxide nanoparticles including ZnO, TiO2, and SiO2 and four bacterial species including Salmonella enterica serovar Newport, Staphylococcus epidermidis, Enterococcus faecalis, and Escherichia coli were included in the test. Results showed that there is no apparent interference of the oxide nanoparticles on quantifications of all four bacterial species by FCM measurement; CFU counting is time consuming, less accurate and not suitable for automation; and the spectrophotometer method using OD measurement was the most unreliable method to quantify and detect the bacteria in the presence of the nanoparticles. Conclusion In summary, FCM measurement proved to be the best method, which is suitable for rapid, accurate and automatic detection of bacteria in the presence of the nanoparticles.
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Affiliation(s)
| | | | | | | | - Huizhong Chen
- Division of Microbiology, National Center for Toxicological Research, U,S, Food and Drug Administration, Jefferson 72079, AR, USA.
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Skinner JP, Swift KM, Ruan Q, Perfetto S, Gratton E, Tetin SY. Simplified confocal microscope for counting particles at low concentrations. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:074301. [PMID: 23902088 PMCID: PMC3724729 DOI: 10.1063/1.4812782] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We describe a compact scanning confocal fluorescence microscope capable of detecting particles concentrations less than 100 particles∕ml in ~15 min. The system mechanically moves a cuvette containing ~3 ml of sample. A relatively large confocal volume is observed within the cuvette using a 1 mm pinhole in front of a detection PMT. Due to the motion of the sample, particles traverse the confocal volume quickly, and analysis by pattern recognition qualifies spikes in the emission intensity data and counts them as events. We show linearity of detection as a function of concentration and also characterize statistical behavior of the instrument. We calculate a detection sensitivity of the system using 3 μm fluorescent microspheres to be 5 particles/ml. Furthermore, to demonstrate biological application, we performed a dilution series to quantify stained E. coli and yeast cells. We counted E. coli cells at a concentration as low as 30 cells∕ml in 10 min/sample.
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Affiliation(s)
- Joseph P Skinner
- Diagnostics Research, Abbott Diagnostics Division, Abbott Park, Illinois 60064, USA
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Ebrahiminezhad A, Ghasemi Y, Rasoul-Amini S, Barar J, Davaran S. Preparation of novel magnetic fluorescent nanoparticles using amino acids. Colloids Surf B Biointerfaces 2013; 102:534-9. [DOI: 10.1016/j.colsurfb.2012.08.046] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Revised: 08/11/2012] [Accepted: 08/28/2012] [Indexed: 10/27/2022]
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Ranzoni A, Sidjabat H, Cooper MA. Nanoparticle sample preparation and mass spectrometry for rapid diagnosis of microbial infections. MICROBIOLOGY AUSTRALIA 2013. [DOI: 10.1071/ma13057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Ebrahiminezhad A, Ghasemi Y, Rasoul-Amini S, Barar J, Davaran S. Impact of Amino-Acid Coating on the Synthesis and Characteristics of Iron-Oxide Nanoparticles (IONs). B KOREAN CHEM SOC 2012. [DOI: 10.5012/bkcs.2012.33.12.3957] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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