ANALYTICAL SCIENCES
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2020
·Vol. 36
·期 12
·1529-1533
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IF 2.049
Zeng Ni,Guo Yaxin,Xiang Juan
Monitoring the changes in the level of KRAS point mutation (the concentration fraction of the KRAS point mutated DNA to the total DNA) in clinical treatment progress can guide and greatly improve the personalized therapy and therapeutic evaluation of patients with cancer. In this work, based on FRET fluorescence quenching and apyrimidinic site-induced guanine/pterin specific binding, we developed a pterin-FAM-TAMRA tri-color fluorescence sensing system to assess the level of KRAS point mutation in one step. The responses from TAMRA displayed good and similar linear correlations in the range from 60 nM to 2 µM for all four types of DNA, resulting in a common linear equation related to the T-DNA concentration ( N aftAMRA = 2.908 c T-DNA + 0.364). Meanwhile, the responses from pterin showed excellent selectivity to W-DNA and an excellent linear correlation to the W-DNA in the concentration range from 60 nM to 1 µM ( N ΔFpterin =–0.364 c gDNA-G + 0.034). This biosensor has an effective concentration range for detecting KRAS point mutations. Especially, because the apyrimidinic site-induced guanine/pterin binding is selective for the detection of wild-type DNA, the sensing system can be applied for clinical mutation level detection of all kinds of KRAS point mutations (G → A, G → C and G → T) in blood samples, which is crucial for the personalized therapy and therapeutic evaluation of patients with most KRAS-related cancer types.
研究领域:
分子生物学
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癌症研究
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生物医学工程
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遗传学
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DOI
PubMed
高影响因子
LUMINESCENCE
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2012
·Vol. 28
·期 6
·860-864
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IF 1.731
Tingting Chen,Leixiaomeng Fu,Lily Zu
Time-resolved fluorescence as well as steady-state absorption and fluorescence were detected in order to study the interactions between tetramethylrhodamine (TAMRA) and DNA when TAMRA was covalently labeled on single- and double-stranded oligonucleotides. Fluorescence intensity quenching and lifetime changes were characterized and correlated with different DNA sequences. The results demonstrated that the photoinduced electron transfer interaction between guanosine residues and TAMRA introduced a short lifetime fluorescence component when guanosine residues were at the TAMRA-attached terminal of the DNA sequences. The discrepancy of two-state and three-state models in previous studies was due to the DNA sequence selection and sensitivity of techniques used to detect the short lifetime component. The results will help the design of fluorescence-based experiments related to a dye labeled probe. Copyright © 2012 John Wiley & Sons, Ltd.
研究领域:
化学
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分子生物学
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生物物理
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DOI
PubMed
高影响因子
CHEMICAL PHYSICS LETTERS
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2010
·
IF 2.291
Chengling Han,Tingting Chen,Lily Zu
A terbium chelate formed with diethylenetriaminepentaacetic acid and p -aminosalicylic acid (Tb–DTPA–pAS) was labeled on a 23-mer DNA strand and used as donor in the fluorescence resonance energy transfer (FRET) study of DNA hybridization. The change in donor fluorescence lifetime with and without DNA-bind acceptor carboxytetramethylrhodamine (TAMRA) showed high energy transfer efficiency (87%). The distance between the two ends of the 23-mer double-stranded DNA was estimated. This study provides a possibility of using the Tb-chelate as a probe in the studies of the geometry-dependent interaction between DNA strands or proteins.
研究领域:
化学
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分子生物学
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生物物理学
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DOI
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 8
·1-10
·
IF 6.408
Zhao Tingting,Yan Weizhen,Dong Fengqi,Hu Xinlong,Xu Yanli,Wang Zhenyu,Shen Yating,Wang Wanrong,Zhao Ye,Wei Wenmei
COVID-19 necessitates the development of reliable and convenient diagnostic tools. In this work, a facile 3D-printed smartphone platform was constructed that achieved reliable visual detection of SARS-CoV-2 by eliminating the effect of ambient light and fixing the camera position relative to the sample. The oligonucleotide probe is modified with orange-red-emitting TAMRA working as an internal standard and green-emitting FAM serving as a sensitive sensing agent. Under 365-nm UV excitation, the emission wavelengths of TAMRA and FAM are 580 nm and 518 nm, respectively. When the probes interact with the targets, the green fluorescence gradually restores while the orange-red fluorescence remains stable. Thus, a striking color transition from orange-red to green could be observed by the naked eye. The detection limit of SARS-CoV-2 nucleic acid is 0.23 nM, and the entire process of color change could be completed in 25 min. Furthermore, the RGB value analysis of the sample solution was conducted using a smartphone for reliable and reproducible discrimination of SARS-CoV-2. The proposed smartphone platform might establish a general method for visual detection of SARS-CoV-2 nucleic acid as well as other virus-related diseases. Graphical abstract
研究领域:
生物医学工程
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分子生物学
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诊断工具
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病毒学
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DOI
PubMed
高影响因子
Scientific Reports
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2020
·Vol. 10
·期 1
·1-8
·
IF 3.998
Tan Xiao-Hui,Li Yu-Bin,Liao Yan,Liu Hua-Zhong
In this work, an enzyme-free fluorescence resonance energy transfer (FRET) strategy was established for rapid and specific detection of the DNA sequence from Vibrio parahaemolyticus (VP) using hybridization chain reaction (HCR) amplification and triplex DNA. The triplex forming oligonucleotide (TFO) was labelled with carboxyfluorescein (FAM) as fluorescence donor, and hairpin sequence H1 was labelled by tetramethylrhodamine (TAMRA) as fluorescence receptor. In the present target VP DNA, the hairpin structure of molecular beacon (MB) was opened, the free end was released and hybridized with H1-TAMRA, and the HCR reaction was triggered by the alternate supplementation of H1-TAMRA and H2 to produce the notch double helix analogue. After the addition of TFO-FAM, a triplex structure was formed between HCR products (H1-TAMRA/H2) and TFO-FAM. A close contact between the donor and the receptor resulted in FRET. Under the optimal conditions, the fluorescence quenching value was inversely proportional to the concentration of target VP DNA in the range of 0.1–50 nmol L −1 , and the detection limit was 35 pmol L −1 .
研究领域:
生物化学
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分子生物学
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分析化学
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微生物学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Yonghao Wang,Dengwang Luo,Yao Fang,Wanhao Wu,Yongjing Wang,Yaokun Xia,Fang Wu,Chunyan Li,Jianming Lan,Jinghua Chen
Exosomes may be used as a crucial medium for the early diagnosis and potential therapy of tumors because of containing a variety of biological information. Therefore, the accurate quantitative analysis of exosomes is especially important in the biomedical field. Herein, we proposed a washing-free aptasensor based on luminescence resonance energy transfer (LRET) between rare-earth doped upconversion nanoparticles (UCNPs) donor and tetramethyl rhodamine (TAMRA) acceptor for highly sensitive detection of exosomes. Therein, the combination of UCNPs and TAMRA can be achieved through the coupling of aptamers to the epithelial cell adhesion molecule (EpCAM), the highly expressed surface proteins of the exosomes. Therefore, when the system of UCNPs-TAMRA in the presence of exosomes is excited by near-infrared light at 980 nm, TAMRA emits yellow fluorescence at 585 nm due to LRET. As a result, the fluorescence intensity at 585 nm is linearly correlated to the concentration of exosomes, which is available for the detection and quantification of exosomes. Under optimal conditions, the proposed approach can reach a low limit of detection (LOD) of 80 particles/μL, and effectively reduce the background signal by using UCNPs as an energy donor. Moreover, this proposed aptasensor can be universally applied to the detection of other targets by strictly screening the aptamers.
研究领域:
生物医学工程
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纳米技术
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癌症诊断
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分子生物学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）