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Shi J, Xu Z, Yang K, Li X, Guo C, Bai H, Fu W, Niu P, Yao J, Yang X. Rapid and noninvasive cell assay by microfluidic-integrated intracavity evanescent field absorption in a fiber ring laser. Anal Chim Acta 2023; 1283:341960. [PMID: 37977802 DOI: 10.1016/j.aca.2023.341960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/14/2023] [Accepted: 10/24/2023] [Indexed: 11/19/2023]
Abstract
BACKGROUND Highly sensitive and rapid detection of cell concentration and interfacial molecular events is of great value for biological, biomedical, and chemical research. Most traditional biosensors require large sample volumes and complicated functional modifications of the surface. It is of great significance to develop label-free biosensor platforms with minimal sample consumption for studying cell concentration changes and interfacial molecular events without labor-intensive procedures. RESULTS Here, a fiber-optic biosensor based on intracavity evanescent field absorption sensing is designed for sensitive and label-free cell assays for the first time. The interaction between the cells and the evanescent field is enhanced by introducing microfluidic-integrated intracavity absorption in a fiber ring laser. This strategy extends the range of targeted analytes to include quantification of a large number of targets on a surface and improves the detection sensitivity of the fiber-optic biosensor. The level of sensing resolution could be improved from 10-4 RIU to 10-7 RIU using this strategy. The stem cells were studied over a wide concentration range (from 500 to 1.2 × 105 cells/ml) and were measured sequentially. By measuring the output power of the intracavity absorption sensing system, the cell concentration can be directly determined in a label-free manner. The results show that dozens of stem cells can be sensitively detected with a sample consumption of 72 μL. The response was fast (15 s) with a low temperature cross-sensitivity of 0.031 cells·ml-1/°C. SIGNIFICANCE The proposed method suggests its capacity for true label-free and noninvasive cell assays with a low limit of detection and small sample consumption. This has the potential to be used as a universal tool for quantitative and qualitative characterization of various cells and other biochemical analytes.
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Affiliation(s)
- Jia Shi
- Tianjin Key Laboratory of Optoelectronic Detection Technology and System, School of Electronic and Information Engineering, Tiangong University, Tianjin, 300387, China; Key Laboratory of Opto-Electronics Information Technology (Ministry of Education), School of Precision Instruments and Opto-Electronic Engineering, Tianjin University, Tianjin, 300072, China.
| | - Ziyi Xu
- Tianjin Key Laboratory of Optoelectronic Detection Technology and System, School of Electronic and Information Engineering, Tiangong University, Tianjin, 300387, China
| | - Ke Yang
- Department of Cardiovascular Surgery, General Hospital of Western Theater Command (Chengdu Military General Hospital), Chengdu, 610036, China.
| | - Xianguo Li
- Tianjin Key Laboratory of Optoelectronic Detection Technology and System, School of Electronic and Information Engineering, Tiangong University, Tianjin, 300387, China
| | - Cuijuan Guo
- Tianjin Key Laboratory of Optoelectronic Detection Technology and System, School of Electronic and Information Engineering, Tiangong University, Tianjin, 300387, China
| | - Hua Bai
- Tianjin Key Laboratory of Optoelectronic Detection Technology and System, School of Electronic and Information Engineering, Tiangong University, Tianjin, 300387, China
| | - Weiling Fu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Pingjuan Niu
- Tianjin Key Laboratory of Optoelectronic Detection Technology and System, School of Electronic and Information Engineering, Tiangong University, Tianjin, 300387, China
| | - Jianquan Yao
- Key Laboratory of Opto-Electronics Information Technology (Ministry of Education), School of Precision Instruments and Opto-Electronic Engineering, Tianjin University, Tianjin, 300072, China
| | - Xiang Yang
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
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Wang X, Li W, Dai S, Dou M, Jiao S, Yang J, Li W, Su Y, Li Q, Li J. High-throughput, highly sensitive and rapid SERS detection of Escherichia coli O157:H7 using aptamer-modified Au@macroporous silica magnetic photonic microsphere array. Food Chem 2023; 424:136433. [PMID: 37244192 DOI: 10.1016/j.foodchem.2023.136433] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 05/29/2023]
Abstract
The aim of this research was to develop a simple, rapid, sensitive, high-throughput detection method for foodborne Escherichia coli (E. coli) O157:H7 based on the aptamer-modified gold nanoparticles@macroporous magnetic silica photonic microsphere (Au@MMSPM). Such Au@MMSPM array system for E. coli O157:H7 not only integrated sample pretreatment with rapid detection, but also showed highly enhanced effect to develop a highly sensitive SERS assay. The established SERS assay platform gave a wide linear detection range (10-106 CFU/mL) and low limit of detection (2.20 CFU/mL) for E. coli O157:H7. The whole analysis time including sample pretreatment and detection was 110 min. This SERS-based assay platform provided a new high-throughput, highly sensitive and fast detection technology for monitoring E. coli O157:H7 in real samples from the fields of food industry, medicine and environment.
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Affiliation(s)
- Xiu Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Wei Li
- Medical Imaging Center, the First Affiliated Hospital, Jinan University, Guangdong 510630, China
| | - Shijie Dai
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Menghua Dou
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Saisai Jiao
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Jing Yang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Weiwei Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Ya Su
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Qianjin Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China.
| | - Jianlin Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China.
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3
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Hadi MU, Khurshid M. SARS-CoV-2 Detection Using Optical Fiber Based Sensor Method. SENSORS (BASEL, SWITZERLAND) 2022; 22:751. [PMID: 35161497 PMCID: PMC8839674 DOI: 10.3390/s22030751] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 01/27/2023]
Abstract
The SARS-CoV-2 Coronavirus disease, also known as the COVID-19 pandemic, has engendered the biggest challenge to human life for the last two years. With a rapid increase in the spread of the Omicron variant across the world, and to contain the spread of COVID-19 in general, it is crucial to rapidly identify this viral infection with minimal logistics. To achieve this, a novel plastic optical fiber (POF) U-shaped probe sensing method is presented for accurate detection of SARS-CoV-2, commonly known as the COVID-19 virus, which has the capability to detect new variants such as Omicron. The sample under test can be taken from oropharyngeal or nasopharyngeal via specific POF U-shaped probe with one end that is fed with a laser source while the other end is connected to a photodetector to receive the response and postprocess for decision-making. The study includes detection comparison with two types of POF with diameters of 200 and 500 µm. Results show that detection is better when a smaller-diameter POF is used. It is also seen that the proposed test bed and its envisaged prototype can detect the COVID-19 variants within 15 min of the test. The proposed approach will make the clinical diagnosis faster, cheaper and applicable to patients in remote areas where there are no hospitals or clinical laboratories due to poverty, geographic obstacles, or other factors.
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Affiliation(s)
| | - Menal Khurshid
- Akbar Niazi Teaching Hospital (ANTH), Islamabad Medical and Dental College (IMDC), Bharakahu, Islamabad 45400, Pakistan;
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Singh M, Raghuwanshi SK. Real-time interrogation of fiber optic biosensor using TiO 2 coated etched long-period grating. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:125001. [PMID: 33379993 DOI: 10.1063/5.0020571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 11/15/2020] [Indexed: 06/12/2023]
Abstract
In this work, a TiO2 coated etched long-period grating (e-LPG) fiber optic biosensor is developed for the detection of Escherichia coli (E. coli) bacteria in food items. Label-free Escherichia coli bacteria monitoring is done over the detection range of 0 cfu/ml-50 cfu/ml using an advanced spectral interrogation mechanism. The thin film deposition of 40 nm TiO2 over the e-LPG is confirmed by the microscopy method, such as scanning electron microscopy. In our proposed biosensor design, T4-bacteriophage is covalently immobilized over the TiO2 coated fiber surface. This biosensor system has reached sensitivity at 2.55 nm/RIU. Our experiments confirm the resolution and the limit of detection (3σ/S) of 0.0039 RIU and 10.05 ppm, respectively. The proposed biosensor with enhanced sensitivity is suitable for monitoring harmful pathogens/infectious agents in various food products.
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Affiliation(s)
- Mandeep Singh
- Department of Electronics and Communication Engineering, National Institute of Technology Karnataka, Surathkal 575025, India
| | - Sanjeev Kumar Raghuwanshi
- Department of Electronics Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad 826004, Jharkhand, India
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Amiri IS, Azzuhri SRB, Jalil MA, Hairi HM, Ali J, Bunruangses M, Yupapin P. Introduction to Photonics: Principles and the Most Recent Applications of Microstructures. MICROMACHINES 2018; 9:mi9090452. [PMID: 30424385 PMCID: PMC6187676 DOI: 10.3390/mi9090452] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/25/2018] [Accepted: 04/04/2018] [Indexed: 11/16/2022]
Abstract
Light has found applications in data transmission, such as optical fibers and waveguides and in optoelectronics. It consists of a series of electromagnetic waves, with particle behavior. Photonics involves the proper use of light as a tool for the benefit of humans. It is derived from the root word “photon”, which connotes the tiniest entity of light analogous to an electron in electricity. Photonics have a broad range of scientific and technological applications that are practically limitless and include medical diagnostics, organic synthesis, communications, as well as fusion energy. This will enhance the quality of life in many areas such as communications and information technology, advanced manufacturing, defense, health, medicine, and energy. The signal transmission methods used in wireless photonic systems are digital baseband and RoF (Radio-over-Fiber) optical communication. Microwave photonics is considered to be one of the emerging research fields. The mid infrared (mid-IR) spectroscopy offers a principal means for biological structure analysis as well as nonintrusive measurements. There is a lower loss in the propagations involving waveguides. Waveguides have simple structures and are cost-efficient in comparison with optical fibers. These are important components due to their compactness, low profile, and many advantages over conventional metallic waveguides. Among the waveguides, optofluidic waveguides have been found to provide a very powerful foundation for building optofluidic sensors. These can be used to fabricate the biosensors based on fluorescence. In an optical fiber, the evanescent field excitation is employed to sense the environmental refractive index changes. Optical fibers as waveguides can be used as sensors to measure strain, temperature, pressure, displacements, vibrations, and other quantities by modifying a fiber. For some application areas, however, fiber-optic sensors are increasingly recognized as a technology with very interesting possibilities. In this review, we present the most common and recent applications of the optical fiber-based sensors. These kinds of sensors can be fabricated by a modification of the waveguide structures to enhance the evanescent field; therefore, direct interactions of the measurand with electromagnetic waves can be performed. In this research, the most recent applications of photonics components are studied and discussed.
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Affiliation(s)
- Iraj Sadegh Amiri
- Division of Materials Science and Engineering, Boston University, Boston, MA 02215, USA.
| | - Saaidal Razalli Bin Azzuhri
- Department of Computer System & Technology, Faculty of Computer Science & Information Technology, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Muhammad Arif Jalil
- Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81300 Johor Bahru, Malaysia.
| | - Haryana Mohd Hairi
- Faculty of Applied Sciences, Universiti Teknologi Mara, Pasir Gudang Campus, 81750 Johor, Malaysia.
| | - Jalil Ali
- Laser Centre, IBNU SINA ISIR, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia.
| | - Montree Bunruangses
- Faculty of Industrial Education, Rajamangala University of Technology Phranakorn, Bangkok 10300, Thailand.
| | - Preecha Yupapin
- Computational Optics Research Group, Advanced Institute of Materials Science, Ton Duc Thang University, District 7, Ho Chi Minh City, Vietnam.
- Faculty of Electrical & Electronics Engineering, Ton Duc Thang University, District 7, Ho Chi Minh City, Vietnam.
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6
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Borosilicate Glass Fiber-Optic Biosensor for the Detection of Escherichia coli. Curr Microbiol 2017; 75:150-155. [PMID: 29063970 DOI: 10.1007/s00284-017-1359-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 09/13/2017] [Indexed: 10/18/2022]
Abstract
Polyclonal antibodies against Escherichia coli and fluorescent, secondary, antibodies were immobilized on borosilicate glass fibers pre-treated with 3-glycidyloxypropyl trimethoxysilane (GPS). Light with an average wavelength of 627 nm, emitted by a diode placed at one end of the glass fiber, was detected by an ultrasensitive photodiode with peak sensitivity at 640 nm. Changes in fluorescence, caused by binding of E. coli to the antibodies, changed the net refractive index of the glass fiber and thus the internal reflection of light. These evanescent changes in photon energy were recorded by an ultrasensitive photodiode. Signals were amplified and changes in voltage recorded with a digital multimeter. A linear increase in voltage readings was recorded over 2 h when 3.0 × 107 CFU/ml and 2.77 × 109 CFU/ml E. coli were adhered to the antibodies. Voltage readings were recorded with E. coli cell numbers from 2 × 103 CFU/ml to 2 × 106 CFU/ml, but readings remained unchanged for 2 h, indicating that the limit of detection is 3.0 × 107 CFU/ml. This simple technology may be used to develop a low-cost, portable, fiber-optic biosensor to detect E. coli in infections and may have applications in the medical field. Research is in progress to optimize the sensitivity of the fiber-optic biosensor and determine its specificity.
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7
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Highly sensitive Escherichia coli shear horizontal surface acoustic wave biosensor with silicon dioxide nanostructures. Biosens Bioelectron 2017; 93:146-154. [DOI: 10.1016/j.bios.2016.09.035] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 08/25/2016] [Accepted: 09/10/2016] [Indexed: 11/20/2022]
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8
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Benito-Peña E, Valdés MG, Glahn-Martínez B, Moreno-Bondi MC. Fluorescence based fiber optic and planar waveguide biosensors. A review. Anal Chim Acta 2016; 943:17-40. [PMID: 27769374 PMCID: PMC7094704 DOI: 10.1016/j.aca.2016.08.049] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 08/25/2016] [Accepted: 08/29/2016] [Indexed: 12/21/2022]
Abstract
The application of optical biosensors, specifically those that use optical fibers and planar waveguides, has escalated throughout the years in many fields, including environmental analysis, food safety and clinical diagnosis. Fluorescence is, without doubt, the most popular transducer signal used in these devices because of its higher selectivity and sensitivity, but most of all due to its wide versatility. This paper focuses on the working principles and configurations of fluorescence-based fiber optic and planar waveguide biosensors and will review biological recognition elements, sensing schemes, as well as some major and recent applications, published in the last ten years. The main goal is to provide the reader a general overview of a field that requires the joint collaboration of researchers of many different areas, including chemistry, physics, biology, engineering, and material science.
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Affiliation(s)
- Elena Benito-Peña
- Department of Analytical Chemistry, Faculty of Chemistry, Complutense University, 28040 Madrid, Spain
| | - Mayra Granda Valdés
- Department of Analytical Chemistry, Faculty of Chemistry, University of La Habana, 10400 La Habana, Cuba
| | - Bettina Glahn-Martínez
- Department of Analytical Chemistry, Faculty of Chemistry, Complutense University, 28040 Madrid, Spain
| | - Maria C Moreno-Bondi
- Department of Analytical Chemistry, Faculty of Chemistry, Complutense University, 28040 Madrid, Spain.
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9
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Jiang S, Qiu H, Gao S, Chen P, Li Z, Yu K, Yue W, Yang C, Huo Y, Wang S. Evanescent Wave Absorption Sensor Based Tapered Plastic Optical Fiber Coated with Monolayer Graphene for Ethanol Molecules Detection. CHINESE J CHEM 2016. [DOI: 10.1002/cjoc.201600271] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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10
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Miller J, Castaneda A, Lee KH, Sanchez M, Ortiz A, Almaz E, Almaz ZT, Murinda S, Lin WJ, Salik E. Biconically tapered fiber optic probes for rapid label-free immunoassays. BIOSENSORS 2015; 5:158-71. [PMID: 25836359 PMCID: PMC4493543 DOI: 10.3390/bios5020158] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 03/16/2015] [Accepted: 03/20/2015] [Indexed: 11/16/2022]
Abstract
We report use of U-shaped biconically tapered optical fibers (BTOF) as probes for label-free immunoassays. The tapered regions of the sensors were functionalized by immobilization of immunoglobulin-G (Ig-G) and tested for detection of anti-IgG at concentrations of 50 ng/mL to 50 µg/mL. Antibody-antigen reaction creates a biological nanolayer modifying the waveguide structure leading to a change in the sensor signal, which allows real-time monitoring. The kinetics of the antibody (mouse Ig-G)-antigen (rabbit anti-mouse IgG) reactions was studied. Hydrofluoric acid treatment makes the sensitive region thinner to enhance sensitivity, which we confirmed by experiments and simulations. The limit of detection for the sensor was estimated to be less than 50 ng/mL. Utilization of the rate of the sensor peak shift within the first few minutes of the antibody-antigen reaction is proposed as a rapid protein detection method.
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Affiliation(s)
- John Miller
- Department of Physics and Astronomy, University of California, Los Angeles, 475 Portola Plaza, Los Angeles, CA 90095, USA.
| | - Angelica Castaneda
- Department of Plant and Microbial Biology, University of California, Berkeley, 565 Li Ka Shing Center, Berkeley, CA 94720, USA.
| | - Kun Ho Lee
- Department of Biological Sciences, California State Polytechnic University, Pomona, 3801 W Temple Ave, Pomona, CA 91768, USA.
| | - Martin Sanchez
- Department of Physics and Astronomy, California State Polytechnic University, Pomona, 3801 W Temple Ave, Pomona, CA 91768, USA.
| | - Adrian Ortiz
- Department of Biological Sciences, California State Polytechnic University, Pomona, 3801 W Temple Ave, Pomona, CA 91768, USA.
| | - Ekrem Almaz
- Department of Physics, Mus Alparslan University, Istasyon Cad. 49100, Mus, Turkey.
| | | | - Shelton Murinda
- Department of Animal and Veterinary Sciences, California State Polytechnic University, Pomona, 3801 W Temple Ave, Pomona, CA 91768, USA.
| | - Wei-Jen Lin
- Department of Biological Sciences, California State Polytechnic University, Pomona, 3801 W Temple Ave, Pomona, CA 91768, USA.
| | - Ertan Salik
- Department of Physics and Astronomy, California State Polytechnic University, Pomona, 3801 W Temple Ave, Pomona, CA 91768, USA.
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11
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Zibaii MI, Latifi H, Saeedian Z, Chenari Z. Nonadiabatic tapered optical fiber sensor for measurement of antimicrobial activity of silver nanoparticles against Escherichia coli. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2014; 135:55-64. [DOI: 10.1016/j.jphotobiol.2014.03.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 02/17/2014] [Accepted: 03/18/2014] [Indexed: 10/25/2022]
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12
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Maloney N, Lukacs G, Ball SL, Hegner M. Device for filamentous fungi growth monitoring using the multimodal frequency response of cantilevers. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:015003. [PMID: 24517802 DOI: 10.1063/1.4854655] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Filamentous fungi cause opportunistic infections in hospital patients. A fast assay to detect viable spores is of great interest. We present a device that is capable of monitoring fungi growth in real time via the dynamic operation of cantilevers in an array. The ability to detect minute frequency shifts for higher order flexural resonance modes is demonstrated using hydrogel functionalised cantilevers. The use of higher order resonance modes sees the sensor dependent mass responsivity enhanced by a factor of 13 in comparison to measurements utilizing the fundamental resonance mode only. As a proof of principle measurement, Aspergillus niger growth is monitored using the first two flexural resonance modes. The detection of single spore growth within 10 h is reported for the first time. The ability to detect and monitor the growth of single spores, within a small time frame, is advantageous in both clinical and industrial settings.
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Affiliation(s)
- N Maloney
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland
| | - G Lukacs
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland
| | - S L Ball
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland
| | - M Hegner
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland
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13
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Tripathi SM, Bock WJ, Mikulic P, Chinnappan R, Ng A, Tolba M, Zourob M. Long period grating based biosensor for the detection of Escherichia coli bacteria. Biosens Bioelectron 2012; 35:308-312. [PMID: 22456096 DOI: 10.1016/j.bios.2012.03.006] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 02/13/2012] [Accepted: 03/03/2012] [Indexed: 11/28/2022]
Abstract
In this paper we report a stable, label-free, bacteriophage-based detection of Escherichia coli (E. coli) using ultra sensitive long-period fiber gratings (LPFGs). Bacteriophage T4 was covalently immobilized on optical fiber surface and the E. coli binding was investigated using the highly accurate spectral interrogation mechanism. In contrast to the widely used surface plasmon resonance (SPR) based sensors, no moving part or metal deposition is required in our sensor, making the present sensor extremely accurate, very compact and cost effective. We demonstrated that our detection mechanism is capable of reliable detection of E. coli concentrations as low as 10(3)cfu/ml with an experimental accuracy greater than 99%.
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Affiliation(s)
- Saurabh Mani Tripathi
- Centre de Recherche en Photonique, Département d'informatique et d'ingénierie, Université du Québec en Outaouais, Gatineau, QC, J8Y 3G5, Canada.
| | - Wojtek J Bock
- Centre de Recherche en Photonique, Département d'informatique et d'ingénierie, Université du Québec en Outaouais, Gatineau, QC, J8Y 3G5, Canada
| | - Predrag Mikulic
- Centre de Recherche en Photonique, Département d'informatique et d'ingénierie, Université du Québec en Outaouais, Gatineau, QC, J8Y 3G5, Canada
| | - Raja Chinnappan
- Institut National de la Recherche Scientifique - Énergie, Matériaux et Télécommunications, Varennes, QC, J3X 1S2, Canada
| | - Andy Ng
- Institut National de la Recherche Scientifique - Énergie, Matériaux et Télécommunications, Varennes, QC, J3X 1S2, Canada
| | - Mona Tolba
- Institut National de la Recherche Scientifique - Énergie, Matériaux et Télécommunications, Varennes, QC, J3X 1S2, Canada
| | - Mohammed Zourob
- Institut National de la Recherche Scientifique - Énergie, Matériaux et Télécommunications, Varennes, QC, J3X 1S2, Canada.
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14
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Dweik M, Stringer RC, Dastider SG, Wu Y, Almasri M, Barizuddin S. Specific and targeted detection of viable Escherichia coli O157:H7 using a sensitive and reusable impedance biosensor with dose and time response studies. Talanta 2012; 94:84-9. [PMID: 22608418 DOI: 10.1016/j.talanta.2012.02.056] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 02/20/2012] [Accepted: 02/22/2012] [Indexed: 01/18/2023]
Abstract
A gold interdigitated microelectrode (IME) impedance biosensor was fabricated for the detection of viable Escherichia coli O157:H7. This sensor was fabricated using lithography techniques. The surface of the electrode was immobilized with anti-E. coli IgG antibodies. This approach is different from other studies where the change in impedance is measured in terms of growth of bacteria on the electrode, rather then the antibody/antigen bonding. The impedance values were recorded for frequency ranges between 100 Hz and 10 MHz. The working range of the dose response for this device was found to be between 2.5×10(4) CFU ml(-1) and 2.5×10(7) CFU ml(-1). The time response studies indicated that antibody/antigen binding is not a function of time, but can decrease if excess times are allowed for binding. It was observed that the impedance values for 60 min antibody/antigen binding were higher than the impedance values for 120 min binding time. The main advantages of the reported device are that, it provides for both qualitative and quantitative detection in 3h while other impedance sensors reported earlier may take up to 24h for detection. If enrichment steps are required then it may take 3-4 days to infer the results. This sensor can be used to detect different types of bacteria by immobilizing the antigen specific antibody. Most of the sensors are not reusable since they either use enzymes or enrichment steps for detection but this device can be reused, following a cleaning protocol which is easy to follow. Each device was used at least five times. The simplicity of this sensor and the ease of fabrication make this sensor a useful alternate to the microfluidics and enzyme based impedance sensors, which are relatively more difficult to fabricate, need programmable fluidic injection pumps to push the sample through the channel, suffer from limitation of coagulation and are difficult to clean.
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Affiliation(s)
- Majed Dweik
- Co-operative Research and Life & Physical Sciences, Lincoln University, Jefferson City, MO 65101, USA
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15
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Lee YJ, Han SR, Maeng JS, Cho YJ, Lee SW. In vitro selection of Escherichia coli O157:H7-specific RNA aptamer. Biochem Biophys Res Commun 2011; 417:414-20. [PMID: 22166202 DOI: 10.1016/j.bbrc.2011.11.130] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 11/28/2011] [Indexed: 12/23/2022]
Abstract
Escherichia coli (E. coli) O157:H7 is a major foodborne pathogen that causes life-threatening symptoms in humans worldwide. To rapidly and properly identify the pathogen and avoid its toxic effects, ligands which can directly and specifically bind to the virulent E. coli O157:H7 serotype should be identified. In this study, a RNA aptamer-based ligand which can specifically distinguish the pathogen E. coli O157:H7 from others was developed by a subtractive cell-SELEX method. To this end, an RNA library was first incubated with the E. coli K12 strain, and the RNAs binding to the strain were discarded. The precluded RNAs were then used for the selection of O157:H7-specific aptamers. After 6 rounds of the subtractive cell-SELEX process, the selected aptamer was found to specifically bind to the O157:H7 serotype, but not to the K12 strain. This was evidenced by aptamer-immobilized ELISA, real-time PCR analysis, or an aptamer-linked precipitation experiment. Importantly, the isolated RNA aptamer that distinguishes between the virulent serotype and the nonpathogenic strain specifically bound to an O157:H7-specific lipopolysaccharide which includes the O antigen. This novel O157:H7-specific aptamer could be of potential application as a diagnostic ligand against the pathogen-related food borne illness.
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Affiliation(s)
- Young Ju Lee
- Department of Molecular Biology, Institute of Nanosensor and Biotechnology, Dankook University, Yongin, Republic of Korea
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16
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A chelating-bond breaking and re-linking technique for rapid re-immobilization of immune micro-sensors. Biomed Microdevices 2011; 14:303-11. [DOI: 10.1007/s10544-011-9607-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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17
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Yuan Y, Ding L. Theoretical investigation for excitation light and fluorescence signal of fiber optical sensor using tapered fiber tip. OPTICS EXPRESS 2011; 19:21515-21523. [PMID: 22109000 DOI: 10.1364/oe.19.021515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
For fiber optical sensor made of tapered fiber tip, the effects of the geometrical parameters of tapered tip on two important factors have been investigated. One factor is the intensity of the evanescent wave into fluorescent layer through core-medium interface; the other is the intensity of fluorescence signal transmitted from fluorescent layer to measurement end. A dependence relation of the intensity of fluorescence signal transmitted from fluorescent layer to measurement end upon the geometrical parameters of tapered tip has been obtained. Theoretical results show that the intensity of the evanescent wave into fluorescent layer rises with the decrease of the end diameter of tapered tip, and the increase of the tip length; and the transmitted power of fluorescence signal increases linearly with the increase of the tip length due to the contribution of the side area of tapered tip.
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Affiliation(s)
- Yinquan Yuan
- National Engineering Laboratory for Fiber Optical Sensing Technology,Wuhan University of Technology, Wuhan 430070, China.
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18
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Beres C, de Nazaré FVB, de Souza NCC, Miguel MAL, Werneck MM. Tapered plastic optical fiber-based biosensor--tests and application. Biosens Bioelectron 2011; 30:328-32. [PMID: 21993139 DOI: 10.1016/j.bios.2011.09.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2011] [Revised: 09/19/2011] [Accepted: 09/20/2011] [Indexed: 10/17/2022]
Abstract
Cells detection is crucial in microbiological analysis of clinical, food, water or environmental samples. However, currently employed methods are time consuming. Plastic optical fiber (POF) biosensors consist in a viable alternative for rapid and inexpensive scheme for detection. In order to study the sensitivity of tapers for microbiological detection, geometric parameters are studied, such as the taper waist diameter since the formation of taper regions are the key sensing element in this particular type of sensors. In this study, a series of POF taper sensors were prepared using a specially developed tapering machine, and the dispersion of geometric dimensions is evaluated, aiming to achieve the best tapering characteristics which will provide a better sensitivity on the sensor response. The fiber tapers that presented the finest results were those constructed in U-shaped (bended) configurations, with taper waist diameters ranging from 0.40 mm up to 0.50 mm. These fiber tapers were used as the main section of the monitoring device, and when chemically treated as immunosensors for the detection of bacteria, yeast and erythrocytes.
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Affiliation(s)
- Carolina Beres
- Photonics and Instrumentation Laboratory, Federal University of Rio de Janeiro, Cidade Universitária, Rio de Janeiro, Brazil
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19
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Bharadwaj R, Sai V, Thakare K, Dhawangale A, Kundu T, Titus S, Verma PK, Mukherji S. Evanescent wave absorbance based fiber optic biosensor for label-free detection of E. coli at 280nm wavelength. Biosens Bioelectron 2011; 26:3367-70. [DOI: 10.1016/j.bios.2010.12.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 11/16/2010] [Accepted: 12/08/2010] [Indexed: 11/26/2022]
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20
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Pereira SV, Raba J, Messina GA. IgG anti-gliadin determination with an immunological microfluidic system applied to the automated diagnostic of the celiac disease. Anal Bioanal Chem 2010; 396:2921-7. [DOI: 10.1007/s00216-010-3589-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2009] [Revised: 02/14/2010] [Accepted: 02/15/2010] [Indexed: 02/06/2023]
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21
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La Belle J, Shah M, Reed J, Nandakumar V, Alford T, Wilson J, Nickerson C, Joshi L. Label-Free and Ultra-Low Level Detection ofSalmonella entericaSerovar Typhimurium Using Electrochemical Impedance Spectroscopy. ELECTROANAL 2009. [DOI: 10.1002/elan.200904666] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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22
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Wang Y, Pang X, Zhang Y, Wang H. Characterization of covalent immobilization on the surface of optical fibers by scanning electron microscopy and energy dispersive X-ray spectrometry. SURF INTERFACE ANAL 2009. [DOI: 10.1002/sia.3091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Antibody-based sensors: principles, problems and potential for detection of pathogens and associated toxins. SENSORS 2009; 9:4407-45. [PMID: 22408533 PMCID: PMC3291918 DOI: 10.3390/s90604407] [Citation(s) in RCA: 190] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 05/26/2009] [Accepted: 05/26/2009] [Indexed: 01/30/2023]
Abstract
Antibody-based sensors permit the rapid and sensitive analysis of a range of pathogens and associated toxins. A critical assessment of the implementation of such formats is provided, with reference to their principles, problems and potential for 'on-site' analysis. Particular emphasis is placed on the detection of foodborne bacterial pathogens, such as Escherichia coli and Listeria monocytogenes, and additional examples relating to the monitoring of fungal pathogens, viruses, mycotoxins, marine toxins and parasites are also provided.
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24
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Meyer WL, Liu Y, Shi XW, Yang X, Bentley WE, Payne GF. Chitosan-Coated Wires: Conferring Electrical Properties to Chitosan Fibers. Biomacromolecules 2009; 10:858-64. [DOI: 10.1021/bm801364h] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- W. Lee Meyer
- Center for Biosystems Research, University of Maryland Biotechnology Institute, 5115 Plant Sciences Building, College Park, Maryland 20742, and Fischell Department of Bioengineering, University of Maryland at College Park, College Park, Maryland 20742
| | - Yi Liu
- Center for Biosystems Research, University of Maryland Biotechnology Institute, 5115 Plant Sciences Building, College Park, Maryland 20742, and Fischell Department of Bioengineering, University of Maryland at College Park, College Park, Maryland 20742
| | - Xiao-Wen Shi
- Center for Biosystems Research, University of Maryland Biotechnology Institute, 5115 Plant Sciences Building, College Park, Maryland 20742, and Fischell Department of Bioengineering, University of Maryland at College Park, College Park, Maryland 20742
| | - Xiaohua Yang
- Center for Biosystems Research, University of Maryland Biotechnology Institute, 5115 Plant Sciences Building, College Park, Maryland 20742, and Fischell Department of Bioengineering, University of Maryland at College Park, College Park, Maryland 20742
| | - William E. Bentley
- Center for Biosystems Research, University of Maryland Biotechnology Institute, 5115 Plant Sciences Building, College Park, Maryland 20742, and Fischell Department of Bioengineering, University of Maryland at College Park, College Park, Maryland 20742
| | - Gregory F. Payne
- Center for Biosystems Research, University of Maryland Biotechnology Institute, 5115 Plant Sciences Building, College Park, Maryland 20742, and Fischell Department of Bioengineering, University of Maryland at College Park, College Park, Maryland 20742
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25
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Kapoor R, Wang CW. Highly specific detection of interleukin-6 (IL-6) protein using combination tapered fiber-optic biosensor dip-probe. Biosens Bioelectron 2009; 24:2696-701. [PMID: 19261461 DOI: 10.1016/j.bios.2009.01.046] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 01/24/2009] [Accepted: 01/30/2009] [Indexed: 11/29/2022]
Abstract
We are reporting highly specific and sensitive detection of human interleukin-6 (IL-6) protein using combination tapered fiber-optic biosensor (CTFOB) dip-probe. With these probes we could successfully detect IL-6, down to a concentration of 5 pM (0.12 ng/ml) in the presence of much higher concentration of a non specific protein. Sandwich immunoassay was used to generate specific fluorescence signal. A novel strategy is developed to eliminate the false signal from non specific binding. In this new strategy it is not required to pre-treat probe surface with any kind of blocking buffer. The specificity of the sensor was established by incubating negative control probes in high concentration (1 nM) of another cytokine IL-8.
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Affiliation(s)
- Rakesh Kapoor
- Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294, United States.
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26
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Nandakumar V, La Belle JT, Reed J, Shah M, Cochran D, Joshi L, Alford T. A methodology for rapid detection of Salmonella typhimurium using label-free electrochemical impedance spectroscopy. Biosens Bioelectron 2008; 24:1045-8. [DOI: 10.1016/j.bios.2008.06.036] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 06/21/2008] [Accepted: 06/24/2008] [Indexed: 10/21/2022]
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27
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Sensing bacteria but treating them well: Determination of optimal incubation and storage conditions. Anal Biochem 2008; 383:68-75. [DOI: 10.1016/j.ab.2008.08.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 08/06/2008] [Accepted: 08/06/2008] [Indexed: 11/17/2022]
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28
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Simpson-Stroot JM, Kearns EA, Stroot PG, Magaña S, Lim DV. Monitoring biosensor capture efficiencies: development of a model using GFP-expressing Escherichia coli O157:H7. J Microbiol Methods 2007; 72:29-37. [PMID: 18096260 DOI: 10.1016/j.mimet.2007.11.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Revised: 11/09/2007] [Accepted: 11/09/2007] [Indexed: 11/15/2022]
Abstract
One of the known limitations for biosensor assays is the high limit of detection for target cells within complex samples (e.g., Escherichia coli at 10(4) to 10(5) CFU/mL) due to poor capture efficiencies. Currently, researchers can only estimate the cell capture efficiency necessary to produce a positive signal for any type of biosensor using either cumbersome techniques or regression modeling. To solve this problem, green fluorescent protein (GFP) transformed E. coli O157:H7 was used to develop a novel method for directly and easily measuring the cell capture efficiency of any given biosensor platform. For demonstration purposes, E. coli-GFP was assayed on both fiber optic and planar waveguide biosensor platforms. Cells were enumerated using an epifluorescent microscope and digital camera to determine the number of cells captured on the surfaces. Conversion algorithms were used with these digital images to determine the cell density of entire waveguide surface areas. For E. coli-GFP, the range of cell capture efficiency was between 0.4 and 1.2%. This indicates that although the developed model works for calculating cell capture, there is still need for significant improvements in capture methods themselves, to increase the capture efficiency and thereby lower detection limits. The use of GFP-transformed target cells and cell capture efficiency calculations can facilitate the development and optimization processes by allowing direct enumeration of new biosensor design configurations and sample processing strategies.
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Affiliation(s)
- Joyce M Simpson-Stroot
- Division of Cell Biology, Microbiology, and Molecular Biology, Department of Biology, University of South Florida, Tampa, FL 33620-5200, USA.
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31
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Maraldo D, Rijal K, Campbell G, Mutharasan R. Method for Label-Free Detection of Femtogram Quantities of Biologics in Flowing Liquid Samples. Anal Chem 2007; 79:2762-70. [PMID: 17309231 DOI: 10.1021/ac0621726] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Rapid (approximately 10 min) measurement of very low concentration of pathogens (approximately 10 cells/mL) and protein (approximately fg/mL) has widespread use in medical diagnostics, monitoring biothreat agents, and in a broader context as a research method. For low-level pathogen, we currently use culture enrichment methods and, thus, rapid analysis is not possible. For low protein concentration, no direct method is currently available. We report here a novel macrocantilever design whose high-order resonant mode near 1 MHz exhibits mass detection sensitivity of 10 cells/mL for cells and 100 fg/mL for protein. The sensor is 1x3 mm and uses a piezoelectric layer for both actuation and sensing resonance. Sample is flowed (approximately 1 mL/min) past the antibody-immobilized sensor, and as antigen binds to the sensor, resonance frequency decreases in proportion to antigen concentration. The sensor showed selectivity to the pathogen even though copious nonpathogenic variant was simultaneously present.
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Affiliation(s)
- David Maraldo
- Department of Chemical and Biological Engineering, Drexel University, Philadelphia, Pennsylvania 19104, USA
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Leung A, Rijal K, Shankar PM, Mutharasan R. Effects of geometry on transmission and sensing potential of tapered fiber sensors. Biosens Bioelectron 2006; 21:2202-9. [PMID: 16406569 DOI: 10.1016/j.bios.2005.11.022] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2005] [Revised: 11/09/2005] [Accepted: 11/23/2005] [Indexed: 11/17/2022]
Abstract
Geometry of tapered fiber sensors critically affects the response of an evanescent field sensor to cell suspensions. Single-mode fibers (nominally at 1300 nm) were tapered to symmetric or asymmetric tapers with diameters in the range of 3-20 microm, and overall lengths of 1-7 mm. Their transmission characteristics in air, water and in the presence of Escherichia coli (JM101 strain) at concentrations of 100, 1000, 7000 and 7 million cells/mL were measured in the 400-800 nm range and gave rich spectral data that lead to the following conclusions. (1) No change in transmission was observed due to E. coli with tapers that showed no relative change in transmission in water compared to air. (2) Tapers that exhibited a significant difference in transmission in water compared to air gave weak response to the presence of the E. coli. Of these, tapers with low waist diameters (6 microm) showed sensitivity to E. coli at 7000 cells/mL and higher concentration. (3) Tapers that showed modest difference in water transmission compared to air, and those that had small waist diameters gave excellent response to E. coli at 100-7000 cells/mL. In addition, mathematical modeling showed that: (1) at low wavelength (470 nm) and small waist diameter (6 microm), transmission with water in the waist region is higher than in air. (2) Small changes in waist diameter (approximately 0.05 microm) can cause larger changes in transmission at 470 nm than at 550 nm at waist diameter of 6 microm. (3) For the same overall geometry, a 5.5 microm diameter taper showed larger refractive index sensitivity compared to a 6.25 microm taper at 470 nm.
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Affiliation(s)
- Angela Leung
- Department of Chemical and Biological Engineering, Drexel University, Philadelphia, PA 19104, USA
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Maraldo D, Shankar PM, Mutharasan R. Measuring bacterial growth by tapered fiber and changes in evanescent field. Biosens Bioelectron 2006; 21:1339-44. [PMID: 15913977 DOI: 10.1016/j.bios.2005.04.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Revised: 04/25/2005] [Accepted: 04/25/2005] [Indexed: 11/23/2022]
Abstract
Single mode continuous tapered fibers were fabricated with waist diameters of 6-8 microm and of 11 mm waist lengths. The tapered surface was coated with poly-l-lysine and Escherichia coli (E. coli) (JM 101) expressing green fluorescent protein was immobilized. Growth of this culture at 22 and 32 degrees C was monitored by 480 nm light transmission through the tapered fiber. Change in transmission is a measure of change in absorption of the evanescent field. The transmission decreased exponentially with cell growth on the tapered surface. Growth rate was determined and compared favorably with cells grown on the same medium in multiwell plates. Significance of the results is that a tapered fiber sensor can be used effectively for rapid assessment to determine the presence of bacteria by growth.
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Affiliation(s)
- David Maraldo
- Department of Chemical Engineering, Drexel University, 32nd and Chestnut Sts, Philadelphia, PA 19104, USA
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