Ferromagnetic Resonance Biosensor for Homogeneous and Volumetric Detection of DNA

2017 ◽  
Author(s):  
Bo Tian ◽  
Peter Svedlindh ◽  
Mattias Strömberg ◽  
Erik Wetterskog
Keyword(s):  
Magnetic Nanoparticles ◽  
Ferromagnetic Resonance ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Rolling Circle Amplification ◽  
Resonance Field ◽  
Isothermal Amplification ◽  
Detection Sensitivity ◽  
Serum Samples ◽  
Rolling Circle

In this work, we demonstrate for the first time, a ferromagnetic resonance (FMR) based homogeneous and volumetric biosensor for magnetic label detection. Two different isothermal amplification methods, <i>i.e.</i>, rolling circle amplification (RCA) and loop-mediated isothermal amplification (LAMP) are adopted and combined with a standard electron paramagnetic resonance (EPR) spectrometer for FMR biosensing. For RCA-based FMR biosensor, binding of RCA products of a synthetic Vibrio cholerae target DNA sequence gives rise to the formation of aggregates of magnetic nanoparticles. Immobilization of nanoparticles within the aggregates leads to a decrease of the net anisotropy of the system and a concomitant increase of the resonance field. A limit of detection of 1 pM is obtained with an average coefficient of variation of 0.16%, which is superior to the performance of other reported RCA-based magnetic biosensors. For LAMP-based sensing, a synthetic Zika virus target oligonucleotide is amplified and detected in 20% serum samples. Immobilization of magnetic nanoparticles is induced by their co-precipitation with Mg<sub>2</sub>P<sub>2</sub>O<sub>7</sub> (a by-product of LAMP) and provides a detection sensitivity of 100 aM. The fast measurement, high sensitivity and miniaturization potential of the proposed FMR biosensing technology makes it a promising candidate for designing future point-of-care devices.<br>

Ferromagnetic Resonance Biosensor for Homogeneous and Volumetric Detection of DNA

2017 ◽  
Author(s):  
Bo Tian ◽  
Peter Svedlindh ◽  
Mattias Strömberg ◽  
Erik Wetterskog
Keyword(s):  
Magnetic Nanoparticles ◽  
Ferromagnetic Resonance ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Rolling Circle Amplification ◽  
Resonance Field ◽  
Isothermal Amplification ◽  
Detection Sensitivity ◽  
Serum Samples ◽  
Rolling Circle

In this work, we demonstrate for the first time, a ferromagnetic resonance (FMR) based homogeneous and volumetric biosensor for magnetic label detection. Two different isothermal amplification methods, <i>i.e.</i>, rolling circle amplification (RCA) and loop-mediated isothermal amplification (LAMP) are adopted and combined with a standard electron paramagnetic resonance (EPR) spectrometer for FMR biosensing. For RCA-based FMR biosensor, binding of RCA products of a synthetic Vibrio cholerae target DNA sequence gives rise to the formation of aggregates of magnetic nanoparticles. Immobilization of nanoparticles within the aggregates leads to a decrease of the net anisotropy of the system and a concomitant increase of the resonance field. A limit of detection of 1 pM is obtained with an average coefficient of variation of 0.16%, which is superior to the performance of other reported RCA-based magnetic biosensors. For LAMP-based sensing, a synthetic Zika virus target oligonucleotide is amplified and detected in 20% serum samples. Immobilization of magnetic nanoparticles is induced by their co-precipitation with Mg<sub>2</sub>P<sub>2</sub>O<sub>7</sub> (a by-product of LAMP) and provides a detection sensitivity of 100 aM. The fast measurement, high sensitivity and miniaturization potential of the proposed FMR biosensing technology makes it a promising candidate for designing future point-of-care devices.<br>

Ultrasensitive SERS-Based Immunoassay of Tumor Marker in Serum Using Au–Ag Alloy Nanoparticles and Ag/AgBr Hybrid Nanostructure

NANO ◽  
2018 ◽  
Vol 13 (01) ◽  
pp. 1850001 ◽  
Author(s):  
Yongfeng Gao ◽  
Yuanhui Feng ◽  
Lu Zhou ◽  
Lucia Petti ◽  
Zhe Wang ◽  
...  
Keyword(s):  
Dynamic Range ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Healthy Person ◽  
Detection Sensitivity ◽  
Hybrid Nanostructure ◽  
Serum Samples ◽  
Broad Dynamic Range ◽  
Surface Enhanced Raman ◽  
Relative Errors

Ultrasensitive detection of alpha-fetoprotein (AFP) is critical for the early diagnosis of liver cancer. In this work, a novel surface-enhanced Raman scattering (SERS)-based immunoassay complex has been successfully developed for the detection of AFP by using the Au-Ag alloy nanoparticals and the Ag/AgBr hybrid nanostructure. As the typical bimetal or metal/semiconductor plasmonic materials, besides the strong SERS enhancement characteristics, the Au-Ag alloy nanoparticals exhibit excellent monodispersity and the Ag/AgBr hybrid nanostructure demonstrates good stability. The experimental results show that the SERS-based immunoassay of AFP presents a low limit of detection of 1.86[Formula: see text]fg/mL and a broad dynamic range from 2[Formula: see text]fg/mL to 0.8[Formula: see text][Formula: see text]g/mL. Furthermore, the clinical applicability of the proposed SERS-based immunoassay has been assessed by the detection of AFP in the human serum samples of cancer patient and healthy person. The test data are consistent well with that of chemiluminescence immunoassay (CLIA) in the relative errors of [Formula: see text]8.82–8.06% and show better detection sensitivity. It reveals that the proposed immunoassay protocol is significant for giving insight into the design of ultrasensitive biosensor and the point-of-care testing of cancers.

scholarly journals Rolling Circle and Loop Mediated Isothermal Amplification Strategy for Ultrasensitive miRNA Detection

Separations ◽  
2021 ◽  
Vol 8 (10) ◽  
pp. 166
Author(s):  
Zheng Cao ◽  
Xianfeng Jiang ◽  
Guizhou Xiao ◽  
Mingcheng Xu ◽  
Hui Liu ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Clinical Sample ◽  
Rolling Circle Amplification ◽  
Isothermal Amplification ◽  
Lamp Method ◽  
Rolling Circle ◽  
Loop Mediated Isothermal Amplification ◽  
Limit Of Quantitation ◽  
Mirna Detection ◽  
Amplification Strategy

Rolling circle amplification (RCA) and loop mediated isothermal amplification (LAMP) were combined to establish the rolling circle and loop mediated isothermal amplification (RC-LAMP) method for miRNA detection. With the participation of Bst 2.0 DNA Polymerase, the method enabled RCA and LAMP amplification to occur simultaneously without thermal cycling. The limit of detection of RC-LAMP was 500 amol/L, which is comparable to previously reported amplification strategies. Moreover, its upper limit of quantitation was higher and showed a stronger resistance to matrix interference. Therefore, it is possible to detect low concentrations of miRNA in samples by increasing the total RNA added. Owing to its facile detection mode and simple operation, this method has great potential in clinical sample detection.

scholarly journals Current and Emerging Technologies for the Diagnosis of SARS-CoV-2

2021 ◽  
Vol 15 (1) ◽  
pp. 77-86
Author(s):  
Davoud Afshar ◽  
Solmaz Ohadian Moghadam ◽  
Siamak Heidarzadeh ◽  
Fatemeh Fardsanei ◽  
Maniya Arshadi ◽  
...  
Keyword(s):  
Reverse Transcription ◽  
Point Of Care ◽  
Rolling Circle Amplification ◽  
Lamp Assay ◽  
Virus Genome ◽  
Isothermal Amplification ◽  
Diagnostic Methods ◽  
World Health ◽  
Serological Tests ◽  
Rolling Circle

Currently, there are numerous under development or developed assays with various sensitivities and specificities for diagnosis of the Coronavirus Disease 2019 (COVID-19) caused by the SARS-CoV-2 virus. The World Health Organization (WHO) has approved several detection protocols based on real-time reverse transcription PCR (RT-qPCR) and the reliability of tests to detect the N, S, or RdRp/Hel genes of the SARS-Cov-2 virus has also investigated. Among these targets, COVID-19-RdRp/Hel targets represented the highest sensitivity. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) has also been developed to rapidly and efficiently amplify RNA under isothermal conditions. Other isothermal amplification approaches such as nucleic acid sequence-based amplification (NASBA), recombinase polymerase amplification (RPA), and rolling circle amplification (RCA) have also been reported for detecting coronaviruses but like LAMP assay. Different serological tests, including neutralization tests, immunofluorescent (IFA), enzyme-linked immunosorbent (ELISA), and western blotting assays, are available. Point-of-care tests (POCT) are emerging to detect the virus genome, IgG, or IgM antibodies against SARS-CoV-2. The advent of more sensitive, cheaper, and easier-to-perform diagnostic tests seems to be a fundamental prerequisite to improve the diagnosis of COVID-19 infection. Herein, we reviewed several commercially available diagnostic methods used in many clinical laboratories to detect COVID-19.

scholarly journals Reverse Transcription Loop-Mediated Isothermal Amplification for the Detection of Porcine Reproductive and Respiratory Syndrome Virus

2009 ◽  
Vol 21 (3) ◽  
pp. 350-354 ◽  
Author(s):  
Albert Rovira ◽  
Juan Abrahante ◽  
Michael Murtaugh ◽  
Muñoz-Zanzi Claudia
Keyword(s):  
Reverse Transcription ◽  
Limit Of Detection ◽  
Restriction Analysis ◽  
Dna Amplification ◽  
Lamp Reaction ◽  
Isothermal Amplification ◽  
Respiratory Syndrome Virus ◽  
Rt Pcr ◽  
Serum Samples ◽  
Loop Mediated Isothermal Amplification

Porcine reproductive and respiratory syndrome virus (PRRSV) is an important pathogen of swine. The objective of the current study is to investigate the feasibility of using reverse transcription loop-mediated isothermal amplification (RT-LAMP) for the detection of PRRSV. The RT-LAMP is a recently described DNA amplification technique reported to be simple, inexpensive, fast, and accurate. The RT-LAMP reaction was set up using 2 sets of primers that were designed to detect North American and European strains of PRRSV and performed successfully in a simple heat block. The specificity of the amplified product was demonstrated by restriction analysis. The RT-LAMP was able to detect 5 different PRRSV isolates. However, the limit of detection ranged between 10 2 and 10 4 50% tissue culture infective dose/ml. The RT-LAMP was further evaluated using serum samples from animals of known infection status. The ability of RT-LAMP to detect PRRSV in serum from acutely infected animals was evaluated with 114 serum samples from 18 experimentally inoculated boars. Forty-nine of these samples tested positive by RT-LAMP, while 94 were positive by reverse transcription polymerase chain reaction (RT-PCR). The diagnostic specificity, evaluated with 100 known negative serum samples, was estimated as 99%. The feasibility of RT-LAMP to detect PRRSV was demonstrated in the current study. The RT-LAMP reaction could be performed in just 1 hr with a simple and inexpensive heat block. However, the sensitivity of this technique was significantly lower than that of RT-PCR.

scholarly journals Integration of isothermal amplification with quantum dot-based fluorescence resonance energy transfer for simultaneous detection of multiple microRNAs

2018 ◽  
Vol 9 (18) ◽  
pp. 4258-4267 ◽  
Author(s):  
Juan Hu ◽  
Ming-hao Liu ◽  
Chun-yang Zhang
Keyword(s):  
Energy Transfer ◽  
Quantum Dot ◽  
Fluorescence Resonance Energy Transfer ◽  
Rolling Circle Amplification ◽  
Simultaneous Detection ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Isothermal Amplification ◽  
Rolling Circle ◽  
Fluorescence Resonance

The integration of quantum dot-based fluorescence resonance energy transfer with rolling circle amplification enables simultaneous sensitive detection of multiple microRNAs.

Highly Sensitive Electrochemical Biosensor for Circulating Tumor Cells Detection via Dual-Aptamer Capture and Rolling Circle Amplification Strategy

2019 ◽  
Vol 15 (7) ◽  
pp. 1568-1577 ◽  
Author(s):  
Yang Wang ◽  
Kai Chang ◽  
Cheng Yang ◽  
Shujing Li ◽  
Lixin Wang ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Circulating Tumor Cells ◽  
Cancer Metastasis ◽  
Electrochemical Biosensor ◽  
Rolling Circle Amplification ◽  
K562 Cells ◽  
Detection Sensitivity ◽  
Experimental Conditions ◽  
Simple Method ◽  
Rolling Circle

A fast and simple strategy for early detection of circulating tumor cells (CTCs) is urgently required because of cancer metastasis. In this work, we assembled an electrochemical biosensor by two aptamers that could form hairpin and specifically recognize K562 cells. The thiolated capture aptamer was fixed on the gold electrode surface. The detection aptamer was linked with a primer at 3 end which could trigger rolling circle amplification to prolong the sequence of aptamer. The dual-aptamer model was fabricated to improve the capture specificity and efficiency for K562 cells. The rolling circle amplification improved the detection sensitivity by inhibiting electron transfer of [Fe(CN)6]3–/4– which could be measured by differential pulse voltammetry. The detection limit of 25 cells mL–1 and linear ranges of 1 × 10 2 to 1 × 105 cells mL–1 were obtained under optimal experimental conditions. Our work exhibited a label-free and simple method for detecting CTCs using cell-specific aptasensor, showing an expected possibility for further CTCs-related study and clinical applications of this novel method.

Sign in / Sign up

Export Citation Format

Share Document