1
|
Zhou Q, Yu R, Xia D, Liu J, Xu W, Yin Y. Diagnosis of Neisseria Gonorrhoeae by Loop-Mediated Isothermal Amplification: Systematic Review and Meta-Analysis. Indian J Microbiol 2022; 62:428-433. [PMID: 35974909 PMCID: PMC9375793 DOI: 10.1007/s12088-022-01013-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/22/2022] [Indexed: 11/05/2022] Open
Abstract
Neisseria gonorrhoeae (gonococci) is the pathogen of gonorrhea. At present, there is no robust statistical analysis targeting the detection accuracy for N.gonorrhoeae of loop-mediated isothermal amplification (LAMP). We performed a full search of five databases for studies using the LAMP method to detect N.gonorrhoeae in this study. Nine datasets derived from eight studies satisfying the inclusion requirement were collected for this study. The pooled sensitivity rate and specificity were calculated as 98.53 and 99.49%. The pooled positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR) were 66.0, 0.04 and 1863.8. After plotting the summary receiver operating characteristic (sROC), the area under the curve (AUC) and Q* index was calculated as 0.99 and 0.9774. Subgroup analyses based on the type of samples, location, and gold standard did not find sources of significant heterogeneity. In conclusion, the LAMP method could be an effective and convenient method with high accuracy for the clinical detection of N.gonorrhoeae. Moreover, the confirmation of this finding needs more high-quality studies with regional data and large samples.
Collapse
Affiliation(s)
- Qian Zhou
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Ruixing Yu
- Department of Dermatology, China-Japan Friendship Hospital, Beijing, China
| | - Deju Xia
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Jingwei Liu
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Wenqi Xu
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Yueping Yin
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| |
Collapse
|
2
|
Priya K, Rathinasabapathi P, Arunraj R, Sugapriya D, Ramya M. Development of multiplex HRM-based loop-mediated isothermal amplification method for specific and sensitive detection of Treponema pallidum. Arch Microbiol 2022; 204:355. [PMID: 35648234 DOI: 10.1007/s00203-022-02973-z] [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: 10/29/2021] [Revised: 04/25/2022] [Accepted: 05/11/2022] [Indexed: 11/25/2022]
Abstract
Syphilis is a sexually transmitted disease caused by the spirochaete bacterium Treponema pallidum. This study has developed a multiplex High-Resolution Melt-curve Loop-mediated isothermal amplification (multiplex HRM-LAMP) assay targeting the marker genes polA and tprL to detect T. pallidum. The multiplex HRM-LAMP assay conditions were optimized at 65 °C for 45 min. Real-time melt-curve analysis of multiplex HRM-LAMP shows two melt-curve peaks corresponding to polA and tprL with a Tm value of 80 ± 0.5 °C and 87 ± 0.5 °C, respectively. The detection limit of multiplex HRM-LAMP was found to be 6.4 × 10-4 ng/μL (3.79 copies/μL) of T. pallidum. The specificity was evaluated using seven different bacterial species, and the developed method was 100% specific in detecting T. pallidum. A total of 64 blood samples of T. pallidum suspected cases were used to validate the assay method. The clinical validation showed that the assay was 96.43% sensitive and 100% specific in detecting syphilis. Thus, the developed method was more rapid and sensitive than other available methods and provides a multigene-based diagnostic approach to detect T. pallidum.
Collapse
Affiliation(s)
- Krishnamoorthy Priya
- Molecular Genetics Laboratory, Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Kanchipuram District, Chennai, Tamil Nadu, 603203, India
| | - Pasupathi Rathinasabapathi
- Molecular Genetics Laboratory, Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Kanchipuram District, Chennai, Tamil Nadu, 603203, India
| | - Rex Arunraj
- Molecular Genetics Laboratory, Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Kanchipuram District, Chennai, Tamil Nadu, 603203, India
| | - Dhanasekaran Sugapriya
- Department of Medical Laboratory (Pathology), College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Wadi-Al Dawaser, 11451, Riyadh, Saudi Arabia
| | - Mohandass Ramya
- Molecular Genetics Laboratory, Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Kanchipuram District, Chennai, Tamil Nadu, 603203, India.
| |
Collapse
|
3
|
Programmable design of isothermal nucleic acid diagnostic assays through abstraction-based models. Nat Commun 2022; 13:1635. [PMID: 35347157 PMCID: PMC8960814 DOI: 10.1038/s41467-022-29101-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 02/24/2022] [Indexed: 02/07/2023] Open
Abstract
Accelerating the design of nucleic acid amplification methods remains a critical challenge in the development of molecular tools to identify biomarkers to diagnose both infectious and non-communicable diseases. Many of the principles that underpin these mechanisms are often complex and can require iterative optimisation. Here we focus on creating a generalisable isothermal nucleic acid amplification methodology, describing the systematic implementation of abstraction-based models for the algorithmic design and application of assays. We demonstrate the simplicity, ease and flexibility of our approach using a software tool that provides amplification schemes de novo, based upon a user-input target sequence. The abstraction of reaction network predicts multiple reaction pathways across different strategies, facilitating assay optimisation for specific applications, including the ready design of multiplexed tests for short nucleic acid sequence miRNAs or for difficult pathogenic targets, such as highly mutating viruses. Detecting nucleic acids often requires choosing between different amplification mechanisms. Here the authors present a generalisable and programmable isothermal methodology, demonstrated in clinical applications, including for multiplexed detection of short miRNAs.
Collapse
|
4
|
Hsieh K, Melendez JH, Gaydos CA, Wang TH. Bridging the gap between development of point-of-care nucleic acid testing and patient care for sexually transmitted infections. LAB ON A CHIP 2022; 22:476-511. [PMID: 35048928 PMCID: PMC9035340 DOI: 10.1039/d1lc00665g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The incidence rates of sexually transmitted infections (STIs), including the four major curable STIs - chlamydia, gonorrhea, trichomoniasis and, syphilis - continue to increase globally, causing medical cost burden and morbidity especially in low and middle-income countries (LMIC). There have seen significant advances in diagnostic testing, but commercial antigen-based point-of-care tests (POCTs) are often insufficiently sensitive and specific, while near-point-of-care (POC) instruments that can perform sensitive and specific nucleic acid amplification tests (NAATs) are technically complex and expensive, especially for LMIC. Thus, there remains a critical need for NAAT-based STI POCTs that can improve diagnosis and curb the ongoing epidemic. Unfortunately, the development of such POCTs has been challenging due to the gap between researchers developing new technologies and healthcare providers using these technologies. This review aims to bridge this gap. We first present a short introduction of the four major STIs, followed by a discussion on the current landscape of commercial near-POC instruments for the detection of these STIs. We present relevant research toward addressing the gaps in developing NAAT-based STI POCT technologies and supplement this discussion with technologies for HIV and other infectious diseases, which may be adapted for STIs. Additionally, as case studies, we highlight the developmental trajectory of two different POCT technologies, including one approved by the United States Food and Drug Administration (FDA). Finally, we offer our perspectives on future development of NAAT-based STI POCT technologies.
Collapse
Affiliation(s)
- Kuangwen Hsieh
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
| | - Johan H Melendez
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Charlotte A Gaydos
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Tza-Huei Wang
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| |
Collapse
|
5
|
Vernon J, Canyelles-Pericas P, Torun H, Dai X, Ng WP, Binns R, Busawon K, Fu YQ. Acousto-Pi: An Opto-Acoustofluidic System Using Surface Acoustic Waves Controlled With Open-Source Electronics for Integrated In-Field Diagnostics. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:411-422. [PMID: 34524958 DOI: 10.1109/tuffc.2021.3113173] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Surface acoustic wave (SAW) devices are increasingly applied in life sciences, biology, and point-of-care applications due to their combined acoustofluidic sensing and actuating properties. Despite the advances in this field, there remain significant gaps in interfacing hardware and control strategies to facilitate system integration with high performance and low cost. In this work, we present a versatile and digitally controlled acoustofluidic platform by demonstrating key functions for biological assays such as droplet transportation and mixing using a closed-loop feedback control with image recognition. Moreover, we integrate optical detection by demonstrating in situ fluorescence sensing capabilities with a standard camera and digital filters, bypassing the need for expensive and complex optical setups. The Acousto-Pi setup is based on open-source Raspberry Pi hardware and 3-D printed housing, and the SAW devices are fabricated with piezoelectric thin films on a metallic substrate. The platform enables the control of droplet position and speed for sample processing (mixing and dilution of samples), as well as the control of temperature based on acousto-heating, offering embedded processing capability. It can be operated remotely while recording the measurements in cloud databases toward integrated in-field diagnostic applications such as disease outbreak control, mass healthcare screening, and food safety.
Collapse
|
6
|
Measurement of the Thermal Effect of Standing Surface Acoustic Waves in Microchannel by Fluoresence Intensity. MICROMACHINES 2021; 12:mi12080934. [PMID: 34442556 PMCID: PMC8401515 DOI: 10.3390/mi12080934] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 07/23/2021] [Accepted: 07/24/2021] [Indexed: 01/10/2023]
Abstract
Temperature is an important parameter for many medical and biological applications. It is key to measuring the temperature of acoustofluidics devices for controlling the device’s temperature. In this paper, Rhodamine B was used to measure the temperature change of the microchannel induced by the SSAWs’ thermal effect in microfluidics. A thermocouple was integrated into the microfluidics device to calibrate the relationship between the fluorescent intensity ratios of Rhodamine B and the temperature. Then, the fluid temperature in the microchannel heated by the SSAWs was measured by the fluorescent signal intensity ratio in the acoustofluidics device. The fluid temperature with different input voltages and different flow rates was measured. The results show that SSAWs can heat the still fluid rapidly to 80 °c, and the flow rates will influence the temperature of the fluid. The results will be useful for precisely controlling the temperature of acoustofluidics devices.
Collapse
|
7
|
Detection of SARS-CoV-2 RNA by a Multiplex Reverse-Transcription Loop-Mediated Isothermal Amplification Coupled with Melting Curves Analysis. Int J Mol Sci 2021; 22:ijms22115743. [PMID: 34072209 PMCID: PMC8197939 DOI: 10.3390/ijms22115743] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/21/2021] [Accepted: 05/24/2021] [Indexed: 12/11/2022] Open
Abstract
Loop-mediated isothermal amplification (LAMP) is a method of nucleic acid amplification that is more stable and resistant to DNA amplification inhibitors than conventional PCR. LAMP multiplexing with reverse transcription allows for the single-tube amplification of several RNA fragments, including an internal control sample, which provides the option of controlling all analytical steps. We developed a method of SARS-CoV-2 viral RNA detection based on multiplex reverse-transcription LAMP, with single-tube qualitative analysis of SARS-CoV-2 RNA and MS2 phage used as a control RNA. The multiplexing is based on the differences in characteristic melting peaks generated during the amplification process. The developed technique detects at least 20 copies of SARS-CoV-2 RNA per reaction on a background of 12,000 MS2 RNA copies. The total time of analysis does not exceed 40 min. The method validation, performed on 125 clinical samples of patients' nasal swabs, showed a 97.6% concordance rate with the results of real-time (RT)-PCR assays. The developed multiplexed LAMP can be employed as an alternative to PCR in diagnostic practice to save personnel and equipment time.
Collapse
|
8
|
Qian J, Huang W, Yang R, Lam RHW, Lee JEY. Low-cost laser-cut patterned chips for acoustic concentration of micro- to nanoparticles and cells by operating over a wide frequency range. Analyst 2021; 146:3280-3288. [PMID: 33999056 DOI: 10.1039/d1an00197c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Acoustofluidic platforms for cell manipulation benefit from being contactless and label-free at potentially low cost. Particle concentration in a droplet relies on augmenting spatial asymmetry in the acoustic field, which is difficult to reproduce reliably. Etching periodic patterns into a chip to create acoustic band gaps is an attractive approach to spatially modify the acoustic field. However, the sensitivity of acoustic band structures to geometrical tolerances requires the use of costly microfabrication processes. In this work, we demonstrate particle concentration across a range of periodic structure patterns fabricated with a laser-cutting tool, suitable for low-cost and low-volume rapid prototyping. The relaxation on precision is underscored by experimental results of equally efficient particle concentration outside band gaps and even in their absence, allowing operation over a range of frequencies independent of acoustic band gaps. These results are significant by indicating the potential of extending the proposed method from the microscale (e.g. tumor cells) to the nanoscale (e.g. bacteria) by scaling up the frequency without being limited by fabrication capabilities. We demonstrate the device's high degree of biocompatibility to illustrate the method's applicability in the biomedical field for applications such as basic biochemical analysis and in vitro diagnosis.
Collapse
Affiliation(s)
- Jingui Qian
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong.
| | | | | | | | | |
Collapse
|
9
|
Zhang L, Tian Z, Bachman H, Zhang P, Huang TJ. A Cell-Phone-Based Acoustofluidic Platform for Quantitative Point-of-Care Testing. ACS NANO 2020; 14:3159-3169. [PMID: 32119517 PMCID: PMC7335639 DOI: 10.1021/acsnano.9b08349] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Acoustofluidic methods, with advantages including simplicity of device design, biocompatible manipulation, and low power consumption, have been touted as promising tools for point-of-care (POC) testing. Here, we report a cell-phone-based acoustofluidic platform that uses acoustic radiation forces to enrich nanoscale analytes and red and green fluorescence nanoparticles (SiO2@R and G@SiO2) as probes for POC visual testing. Thus, the color signals from the fluorescent probes are enhanced, and colorimetric sensitivity is significantly improved. As a POC demonstration, the acoustofluidic platform is used to detect hemoglobin (Hb) from human blood, resulting in a rapid and straightforward measurement of normal blood Hb levels. Combining an acoustofluidic-based nanoparticle-concentration platform with cell-phone-based colorimetry, our method introduces a potential pathway toward practical POC testing.
Collapse
Affiliation(s)
- Liying Zhang
- School of Pharmacy, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Mechanical Engineering and Material Science, Duke University, Durham, North Carolina 27708, United States
| | - Zhenhua Tian
- Department of Aerospace Engineering, Mississippi State University, Mississippi State, Mississippi 39762, United States
- Department of Mechanical Engineering and Material Science, Duke University, Durham, North Carolina 27708, United States
| | - Hunter Bachman
- Department of Mechanical Engineering and Material Science, Duke University, Durham, North Carolina 27708, United States
| | - Peiran Zhang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, North Carolina 27708, United States
| | - Tony Jun Huang
- Department of Mechanical Engineering and Material Science, Duke University, Durham, North Carolina 27708, United States
| |
Collapse
|
10
|
Lim H, Back SM, Choi H, Nam J. Acoustic mixing in a dome-shaped chamber-based SAW (DC-SAW) device. LAB ON A CHIP 2020; 20:120-125. [PMID: 31723954 DOI: 10.1039/c9lc00820a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The use of an open droplet system for surface acoustic wave (SAW)-based applications has been limited by droplet instability at high input power. This study introduces a dome-shaped chamber-based SAW (DC-SAW) device for the first time, which can be fabricated simply using a single adhesive tape and a drop of ultraviolet-curable material without soft lithography processes. The dome-shaped chamber device with a contact angle of 68° enables the maximizing of the effect of SAW transmitted at a refraction angle of roughly 22°, negating the droplet instability. The DC-SAW device was applied to acoustic mixing to estimate its capability. Acoustic mixing of two different fluids (i.e., deionized water and fluorescent particle suspension) was demonstrated in the dome-shaped chamber device. Moreover, the effect of flow rate and applied voltage on mixing performance was estimated. With the decreasing flow rate and increasing applied voltage, mixing performance was enhanced. At an applied voltage of 20 V, mixing indices were higher than 0.9 at a total flow rate of 300 μl min-1.
Collapse
Affiliation(s)
- Hyunjung Lim
- Department of Medical Sciences, Graduate School of Medicine, Korea University, Seoul, Korea.
| | - Seung Min Back
- Department of Medical Sciences, Graduate School of Medicine, Korea University, Seoul, Korea.
| | - Hyuk Choi
- Department of Medical Sciences, Graduate School of Medicine, Korea University, Seoul, Korea.
| | - Jeonghun Nam
- Department of Laboratory Medicine, College of Medicine, Korea University Guro Hospital, Korea University, Seoul, Korea. and Department of Emergency Medicine, College of Medicine, Korea University Guro Hospital, Korea University, Seoul, Korea
| |
Collapse
|
11
|
Nam J, Jang WS, Kim J, Lee H, Lim CS. Lamb wave-based molecular diagnosis using DNA hydrogel formation by rolling circle amplification (RCA) process. Biosens Bioelectron 2019; 142:111496. [PMID: 31302395 DOI: 10.1016/j.bios.2019.111496] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/10/2019] [Accepted: 07/07/2019] [Indexed: 11/25/2022]
Abstract
Recent developments in microfluidics enable the lab-on-a-chip-based molecular diagnosis. Rapid and accurate diagnosis of infectious diseases is critical for preventing the transmission of the disease. Here, we characterize a Lamb wave-based device using various parameters including the contact angle and viscosity of the sample droplet, the applied voltage, and the temperature increase. Additionally, we demonstrate the functionality of the Lamb wave-based device in clinical application. Optimal temperature for rolling circle amplification (RCA) process is 30 °C, and it was achieved by Lamb wave generation at 17 V. Gene amplification due to RCA process could be detected by viscosity increase due to DNA hydrogel formation in a sample droplet, which induced the acoustic streaming velocity of suspended particles to be decreased. In our Lamb wave-based device, isothermal amplification of target nucleic acids could be successfully detected within 30 min using 10 μL of sessile droplet, and was validated by comparing that of commercial real-time fluorescence analysis. Our device enables simple and low-cost molecular diagnosis, which can be applied to resource-limited clinical settings.
Collapse
Affiliation(s)
- Jeonghun Nam
- Department of Laboratory Medicine, College of Medicine, Korea University, Seoul, South Korea; Department of Emergency Medicine, College of Medicine, Korea University, Seoul, South Korea.
| | - Woong Sik Jang
- Department of Laboratory Medicine, College of Medicine, Korea University, Seoul, South Korea; Department of Emergency Medicine, College of Medicine, Korea University, Seoul, South Korea
| | - Jisu Kim
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, South Korea
| | - Hyukjin Lee
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, South Korea
| | - Chae Seung Lim
- Department of Laboratory Medicine, College of Medicine, Korea University, Seoul, South Korea.
| |
Collapse
|
12
|
Zhang J, Su X, Xu J, Wang J, Zeng J, Li C, Chen W, Li T, Min X, Zhang D, Zhang S, Ge S, Zhang J, Xia N. A point of care platform based on microfluidic chip for nucleic acid extraction in less than 1 minute. BIOMICROFLUIDICS 2019; 13:034102. [PMID: 31123534 PMCID: PMC6506337 DOI: 10.1063/1.5088552] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 04/19/2019] [Indexed: 05/25/2023]
Abstract
In view of the complex procedure of nucleic acid extraction, there exists a huge challenge for the widespread use of point-of-care diagnostics for nucleic acid testing. To achieve point-of-care applications in a more rapid and cost-efficient manner, we designed a snake pipe-shaped microfluidic chip so as to accomplish reagents-prestored, time-saving, operation-simple nucleic acid extraction. All reagents needed for this process, including lysis buffer, wash buffer, elution buffer, and so on, were preloaded in the snake pipe and securely isolated by membrane valves, without the need for using any specialized equipment. By an integrated chip and a powerful ultrasonic, this device could complete virus nucleic acid extraction from sophisticated serum samples in less than 1 min. We used hepatitis B virus (HBV) and human immunodeficiency virus (HIV) mixed with different sources of serum as samples to be extracted. The coefficient of variation of HBV and HIV extraction on-chip was 1.32% and 2.74%, respectively, and there were no significant differences between on-chip and commercial instrument extraction (P > 0.05, α = 0.05) in different dilution ratios, which showed that the extraction device we established had excellent stability and sensitivity.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Shiyin Zhang
- Authors to whom correspondence should be addressed: and
| | - Shengxiang Ge
- Authors to whom correspondence should be addressed: and
| | | | | |
Collapse
|
13
|
Dong J, Xu Q, Li CC, Zhang CY. Single-color multiplexing by the integration of high-resolution melting pattern recognition with loop-mediated isothermal amplification. Chem Commun (Camb) 2019; 55:2457-2460. [PMID: 30734782 DOI: 10.1039/c8cc09741k] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We develop a single-color multiplexing strategy by the integration of high-resolution melting pattern recognition with loop-mediated isothermal amplification (LAMP). This strategy can identify multiple amplicons with a small DNA melting temperature (Tm) difference (∼0.2 °C) without the involvement of either multicolor labels or parallelized multiplexing, and it can sensitively detect LAMP amplicons with the initial DNA concentrations ranging from 10 to 108 copies.
Collapse
Affiliation(s)
- Jing Dong
- School of Food and Biological Engineering, National R&D Center for Goat Dairy Products Processing Technology, Shaanxi University of Science and Technology, Xi'an, 710021, China.
| | | | | | | |
Collapse
|
14
|
Shu B, Li Z, Yang X, Xiao F, Lin D, Lei X, Xu B, Liu D. Active droplet-array (ADA) microfluidics enables multiplexed complex bioassays for point of care testing. Chem Commun (Camb) 2018; 54:2232-2235. [PMID: 29431774 DOI: 10.1039/c7cc09377b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We introduce a novel and versatile microfluidic technology that allows parallel and multi-step bioanalytical procedures to be simply implemented by switching reagent-containing droplet arrays among alternative interaction zones for intended mass or energy transport in a programmable manner. This enables multiplexed complex bioassays for point-of-care testing.
Collapse
Affiliation(s)
- Bowen Shu
- Department of Laboratory Medicine, Guangzhou First People's Hospital, Guangzhou Medical University, Guangzhou 510180, China
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Zhao Z, Bao Y, Chu LT, Ho JKL, Chieng CC, Chen TH. Microfluidic bead trap as a visual bar for quantitative detection of oligonucleotides. LAB ON A CHIP 2017; 17:3240-3245. [PMID: 28869261 DOI: 10.1039/c7lc00836h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We demonstrate a microfluidic bead trap capable of forming a dipstick-type bar visible to the naked eye for simple and quantitative detection of oligonucleotides. We use magnetic microparticles (MMPs) and polystyrene microparticles (PMPs) that are connected and form MMPs-targets-PMPs when target oligonucleotides are present, leaving free PMPs with a number inversely proportional to the amount of targets. Using a capillary flow-driven microfluidic circuitry consisting of a magnetic separator to remove the MMPs-targets-PMPs, the free PMPs can be trapped at the narrowing nozzle downstream, forming a visual bar quantifiable based on the length of PMP accumulation. Such a power-free and instrument-free platform enables a limit of detection at 13 fmol (0.65 nM in 20 μl, S/N = 3) of oligonucleotides and is compatible with single-nucleotide polymorphisms and operation in a complex bio-fluid. Moreover, using DNAzyme as the target oligonucleotide that catalyzes a specific hydrolytic cleavage in the presence of lead ions, we demonstrate a model application that detects lead ions with a limit of detection of 12.2 nM (2.5 μg l-1), providing quantitative and visual detection of lead contamination at resource-limited sites.
Collapse
Affiliation(s)
- Zichen Zhao
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong Special Administrative Region.
| | | | | | | | | | | |
Collapse
|
16
|
Destgeer G, Jung JH, Park J, Ahmed H, Sung HJ. Particle Separation inside a Sessile Droplet with Variable Contact Angle Using Surface Acoustic Waves. Anal Chem 2016; 89:736-744. [DOI: 10.1021/acs.analchem.6b03314] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Ghulam Destgeer
- Department of Mechanical
Engineering, KAIST, Daejeon 34141, Korea
| | - Jin Ho Jung
- Department of Mechanical
Engineering, KAIST, Daejeon 34141, Korea
| | - Jinsoo Park
- Department of Mechanical
Engineering, KAIST, Daejeon 34141, Korea
| | - Husnain Ahmed
- Department of Mechanical
Engineering, KAIST, Daejeon 34141, Korea
| | - Hyung Jin Sung
- Department of Mechanical
Engineering, KAIST, Daejeon 34141, Korea
| |
Collapse
|
17
|
Rapid Salmonella detection using an acoustic wave device combined with the RCA isothermal DNA amplification method. SENSING AND BIO-SENSING RESEARCH 2016. [DOI: 10.1016/j.sbsr.2016.10.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
18
|
Gao N, Gao F, He S, Zhu Q, Huang J, Tanaka H, Wang Q. Graphene oxide directed in-situ deposition of electroactive silver nanoparticles and its electrochemical sensing application for DNA analysis. Anal Chim Acta 2016; 951:58-67. [PMID: 27998486 DOI: 10.1016/j.aca.2016.11.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/16/2016] [Accepted: 11/21/2016] [Indexed: 12/15/2022]
Abstract
The development of high-performance biosensing platform is heavily dependent on the recognition property of the sensing layer and the output intensity of the signal probe. Herein, we present a simple and highly sensitive biosensing interface for DNA detection on the basis of graphene oxide nanosheets (GONs) directed in-situ deposition of silver nanoparticles (AgNPs). The fabrication process and electrochemical properties of the biosensing interface were probed by electrochemical techniques and scanning electron microscopy. The results indicate that GONs can specifically adsorb at the single-stranded DNA probe surface, and induces the deposition of highly electroactive AgNPs. Upon hybridization with complementary oligonucleotides to generate the duplex DNA on the electrode surface, the GONs with the deposited AgNPs will be liberated from the sensing interface due to the inferior affinity of GONs and duplex DNA, resulting in the reduction of the electrochemical signal. Such a strategy combines the superior recognition of GONs toward single-stranded DNA and double-stranded DNA, and the strong electrochemical response of in-situ deposited AgNPs. Under optimal conditions, the biosensor can detect target DNA over a wide range from 10 fM to 10 nM with a detection limit of 7.6 fM. Also, the developed biosensor shows outstanding discriminating ability toward oligonucleotides with different mismatching degrees.
Collapse
Affiliation(s)
- Ningning Gao
- College of Chemistry and Environment, Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, PR China
| | - Feng Gao
- College of Chemistry and Environment, Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, PR China; Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan.
| | - Suyu He
- College of Chemistry and Environment, Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, PR China
| | - Qionghua Zhu
- College of Chemistry and Environment, Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, PR China
| | - Jiafu Huang
- College of Chemistry and Environment, Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, PR China
| | - Hidekazu Tanaka
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Qingxiang Wang
- College of Chemistry and Environment, Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, PR China.
| |
Collapse
|
19
|
Xu G, Zhao H, Cooper JM, Reboud J. A capillary-based multiplexed isothermal nucleic acid-based test for sexually transmitted diseases in patients. Chem Commun (Camb) 2016; 52:12187-12190. [PMID: 27722490 PMCID: PMC5058349 DOI: 10.1039/c6cc05679b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 09/08/2016] [Indexed: 11/21/2022]
Abstract
We demonstrate a multiplexed loop mediated isothermal amplification (LAMP) assay for infectious disease diagnostics, where the analytical process flow of target pathogens genomic DNA is performed manually by moving magnetic beads through a series of plugs in a capillary. Heat is provided by a water bath and the results are read by the naked eye, enabling applications in low resource settings.
Collapse
Affiliation(s)
- Gaolian Xu
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Oakfield Avenue, Rankine Building, G12 8LT Glasgow, UK.
| | - Hang Zhao
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Oakfield Avenue, Rankine Building, G12 8LT Glasgow, UK.
| | - Jonathan M Cooper
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Oakfield Avenue, Rankine Building, G12 8LT Glasgow, UK.
| | - Julien Reboud
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Oakfield Avenue, Rankine Building, G12 8LT Glasgow, UK.
| |
Collapse
|
20
|
Xu G, Nolder D, Reboud J, Oguike MC, van Schalkwyk DA, Sutherland CJ, Cooper JM. Paper-Origami-Based Multiplexed Malaria Diagnostics from Whole Blood. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606060] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gaolian Xu
- Division of Biomedical Engineering, School of Engineering; University of Glasgow; Oakfield Avenue Glasgow G12 8LT UK
| | - Debbie Nolder
- Public Health England Malaria Reference Laboratory (PHE MRL); Faculty of Infectious & Tropical Diseases; London School of Hygiene & Tropical Medicine; UK
| | - Julien Reboud
- Division of Biomedical Engineering, School of Engineering; University of Glasgow; Oakfield Avenue Glasgow G12 8LT UK
| | - Mary C. Oguike
- Dept of Immunology & Infection; Faculty of Infectious & Tropical Diseases; London School of Hygiene & Tropical Medicine; UK
| | - Donelly A. van Schalkwyk
- Dept of Immunology & Infection; Faculty of Infectious & Tropical Diseases; London School of Hygiene & Tropical Medicine; UK
| | - Colin J. Sutherland
- Public Health England Malaria Reference Laboratory (PHE MRL); Faculty of Infectious & Tropical Diseases; London School of Hygiene & Tropical Medicine; UK
- Dept of Immunology & Infection; Faculty of Infectious & Tropical Diseases; London School of Hygiene & Tropical Medicine; UK
| | - Jonathan M. Cooper
- Division of Biomedical Engineering, School of Engineering; University of Glasgow; Oakfield Avenue Glasgow G12 8LT UK
| |
Collapse
|
21
|
Xu G, Nolder D, Reboud J, Oguike MC, van Schalkwyk DA, Sutherland CJ, Cooper JM. Paper-Origami-Based Multiplexed Malaria Diagnostics from Whole Blood. Angew Chem Int Ed Engl 2016; 55:15250-15253. [PMID: 27554333 PMCID: PMC5132111 DOI: 10.1002/anie.201606060] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Indexed: 12/22/2022]
Abstract
We demonstrate, for the first time, the multiplexed determination of microbial species from whole blood using the paper‐folding technique of origami to enable the sequential steps of DNA extraction, loop‐mediated isothermal amplification (LAMP), and array‐based fluorescence detection. A low‐cost handheld flashlight reveals the presence of the final DNA amplicon to the naked eye, providing a “sample‐to‐answer” diagnosis from a finger‐prick volume of human blood, within 45 min, with minimal user intervention. To demonstrate the method, we showed the identification of three species of Plasmodium, analyzing 80 patient samples benchmarked against the gold‐standard polymerase chain reaction (PCR) assay in an operator‐blinded study. We also show that the test retains its diagnostic accuracy when using stored or fixed reference samples.
Collapse
Affiliation(s)
- Gaolian Xu
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Oakfield Avenue, Glasgow, G12 8LT, UK
| | - Debbie Nolder
- Public Health England Malaria Reference Laboratory (PHE MRL), Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, UK
| | - Julien Reboud
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Oakfield Avenue, Glasgow, G12 8LT, UK
| | - Mary C Oguike
- Dept of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, UK
| | - Donelly A van Schalkwyk
- Dept of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, UK
| | - Colin J Sutherland
- Public Health England Malaria Reference Laboratory (PHE MRL), Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, UK.,Dept of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, UK
| | - Jonathan M Cooper
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Oakfield Avenue, Glasgow, G12 8LT, UK
| |
Collapse
|
22
|
Facile construction of a highly sensitive DNA biosensor by in-situ assembly of electro-active tags on hairpin-structured probe fragment. Sci Rep 2016; 6:22441. [PMID: 26931160 PMCID: PMC4773755 DOI: 10.1038/srep22441] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 02/15/2016] [Indexed: 01/04/2023] Open
Abstract
An ultrasensitive DNA biosensor has been developed through in-situ labeling of electroactive melamine-Cu2+ complex (Mel-Cu2+) on the end of hairpin-like probe using gold nanoparticles (AuNPs) as the signal amplification platform. The 3′-thiolated hairpin-like probe was first immobilized to the gold electrode surface by the Au-S bond. The AuNPs were then tethered on the free 5′-end of the immobilized probe via the special affinity between Au and the modified -NH2. Followed by, the Mel and Cu2+ were assembled on the AuNPs surface through Au-N bond and Cu2+-N bond, respectively. Due to the surface area and electrocatalytic effects of the AuNPs, the loading amount and electron transfer kinetic of the Mel-Cu2+ were enhanced greatly, resulting in significantly enhanced electrochemical response of the developed biosensor. Compared with the synthesis process of conventional electroactive probe DNA accomplished by homogeneous method, the method presented in this work is more reagent- and time-saving. The proposed biosensor showed high selectivity, wide linear range and low detection limit. This novel strategy could also be extended to the other bioanalysis platforms such as immunosensors and aptasensors.
Collapse
|
23
|
Destgeer G, Cho H, Ha BH, Jung JH, Park J, Sung HJ. Acoustofluidic particle manipulation inside a sessile droplet: four distinct regimes of particle concentration. LAB ON A CHIP 2016; 16:660-7. [PMID: 26755271 DOI: 10.1039/c5lc01104c] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In this study, we have investigated the motion of polystyrene microparticles inside a sessile droplet of water actuated by surface acoustic waves (SAWs), which produce an acoustic streaming flow (ASF) and impart an acoustic radiation force (ARF) on the particles. We have categorized four distinct regimes (R1-R4) of particle aggregation that depend on the particle diameter, the SAW frequency, the acoustic wave field (travelling or standing), the acoustic waves' attenuation length, and the droplet volume. The particles are concentrated at the centre of the droplet in the form of a bead (R1), around the periphery of the droplet in the form of a ring (R2), at the side of the droplet in the form of an isolated island (R3), and close to the centre of the droplet in the form of a smaller ring (R4). The ASF-based drag force, the travelling or standing SAW-based ARF, and the centrifugal force are utilized in various combinations to produce these distinct regimes. For simplicity, we fixed the fluid volume at 5 μL, varied the SAW actuation frequency (10, 20, 80, and 133 MHz), and tested several particle diameters in the range 1-30 μm to explicitly demonstrate the regimes R1-R4. We have further demonstrated the separation of particles (1 and 10 μm, 3 and 5 μm) using mixed regime configurations (R1 and R2, R2 and R4, respectively).
Collapse
Affiliation(s)
- Ghulam Destgeer
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea.
| | | | | | | | | | | |
Collapse
|
24
|
Kanitkar YH, Stedtfeld RD, Steffan RJ, Hashsham SA, Cupples AM. Loop-Mediated Isothermal Amplification (LAMP) for Rapid Detection and Quantification of Dehalococcoides Biomarker Genes in Commercial Reductive Dechlorinating Cultures KB-1 and SDC-9. Appl Environ Microbiol 2016; 82:1799-1806. [PMID: 26746711 PMCID: PMC4784023 DOI: 10.1128/aem.03660-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 12/27/2015] [Indexed: 12/23/2022] Open
Abstract
Real-time quantitative PCR (qPCR) protocols specific to the reductive dehalogenase (RDase) genes vcrA, bvcA, and tceA are commonly used to quantify Dehalococcoides spp. in groundwater from chlorinated solvent-contaminated sites. In this study, loop-mediated isothermal amplification (LAMP) was developed as an alternative approach for the quantification of these genes. LAMP does not require a real-time thermal cycler (i.e., amplification is isothermal), allowing the method to be performed using less-expensive and potentially field-deployable detection devices. Six LAMP primers were designed for each of three RDase genes (vcrA, bvcA, and tceA) using Primer Explorer V4. The LAMP assays were compared to conventional qPCR approaches using plasmid standards, two commercially available bioaugmentation cultures, KB-1 and SDC-9 (both contain Dehalococcoides species). DNA was extracted over a growth cycle from KB-1 and SDC-9 cultures amended with trichloroethene and vinyl chloride, respectively. All three genes were quantified for KB-1, whereas only vcrA was quantified for SDC-9. A comparison of LAMP and qPCR using standard plasmids indicated that quantification results were similar over a large range of gene concentrations. In addition, the quantitative increase in gene concentrations over one growth cycle of KB-1 and SDC-9 using LAMP was comparable to that of qPCR. The developed LAMP assays for vcrA and tceA genes were validated by comparing quantification on the Gene-Z handheld platform and a real-time thermal cycler using DNA isolated from eight groundwater samples obtained from an SDC-9-bioaugmented site (Tulsa, OK). These assays will be particularly useful at sites subject to bioaugmentation with these two commonly used Dehalococcoides species-containing cultures.
Collapse
Affiliation(s)
- Yogendra H Kanitkar
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan, USA
| | - Robert D Stedtfeld
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan, USA
| | - Robert J Steffan
- Biotechnology Development and Applications Group, CB&I Federal Services, LLC, Lawrenceville, New Jersey, USA
| | - Syed A Hashsham
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan, USA
- Center for Microbial Ecology, Michigan State University, East Lansing, Michigan, USA
| | - Alison M Cupples
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan, USA
| |
Collapse
|
25
|
Lu M, Xu L, Zhang X, Xiao R, Wang Y. Ag(I)-coordinated hairpin DNA for homogenous electronic monitoring of hepatitis C virus accompanying isothermal cycling signal amplification strategy. Biosens Bioelectron 2015; 73:195-201. [DOI: 10.1016/j.bios.2015.05.058] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 05/07/2015] [Accepted: 05/26/2015] [Indexed: 12/18/2022]
|
26
|
Papadakis G, Skandalis N, Dimopoulou A, Glynos P, Gizeli E. Bacteria Murmur: Application of an Acoustic Biosensor for Plant Pathogen Detection. PLoS One 2015; 10:e0132773. [PMID: 26177507 PMCID: PMC4503732 DOI: 10.1371/journal.pone.0132773] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 06/19/2015] [Indexed: 12/13/2022] Open
Abstract
A multi-targeting protocol for the detection of three of the most important bacterial phytopathogens, based on their scientific and economic importance, was developed using an acoustic biosensor (the Quartz Crystal Microbalance) for DNA detection. Acoustic detection was based on a novel approach where DNA amplicons were monitored and discriminated based on their length rather than mass. Experiments were performed during real time monitoring of analyte binding and in a direct manner, i.e. without the use of labels for enhancing signal transduction. The proposed protocol improves time processing by circumventing gel electrophoresis and can be incorporated as a routine detection method in a diagnostic lab or an automated lab-on-a-chip system for plant pathogen diagnostics.
Collapse
Affiliation(s)
- George Papadakis
- Institute of Molecular Biology and Biotechnology, Heraklion Crete, Greece
| | - Nicholas Skandalis
- Benaki Phytopathological Institute, 8 St. Delta, Kifissia, Athens, Greece
| | | | - Paraskevas Glynos
- Benaki Phytopathological Institute, 8 St. Delta, Kifissia, Athens, Greece
| | - Electra Gizeli
- Institute of Molecular Biology and Biotechnology, Heraklion Crete, Greece
- Dept. of Biology, University of Crete, Vassilika Vouton, Heraklion Crete, Greece
| |
Collapse
|