Analytical Methods
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2015
·Vol. 7
·期 16
·6712-6717
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IF 1.821
Weiwen Hu,Yong Ning,Lianzhi Li,Jinming Kong,Xueji Zhang
In this work, a highly effective biosensor supported on morpholino-functionalized magnetic microspheres was investigated for the sequence-specific detection of DNA. Briefly, morpholino was first modified on the surface of magnetic microspheres through amido bonds, and then hybridized with target DNA in the ensuing step. Biotin-labeled signal probe DNA was designed to hybridize with the DNA nearby the 5′ end of sequence, and the biotin was used to bind with streptavidin-alkaline phosphatase (SA-ALP). L-Ascorbic acid-2-phosphate (AAP) was hydrolyzed by ALP to generate L-ascorbic acid, which could reduce resazurin to resorufin, resulting in a turn-on fluorescence signal. UV-vis absorbance spectroscopy was applied to prove the conjugation of ALP with signal probe DNA. Under optimal conditions, this biosensor displayed a good linear relationship between the fluorescence intensity and logarithm of single-stranded DNA concentrations in the range of 0.1 pM to 0.1 nM with a low detection limit of 9.32 fM. Moreover, fully complementary versus single-base mismatched, three-base mismatched and non-complementary DNA could be effectively distinguished. In addition, this novel approach rendered satisfactory analytical results for the determination of DNA in serum, thus exhibiting practical significance. These results demonstrated that this assay method displays excellent sensitivity and specificity for DNA detection and has great potential for practical applications.
研究领域:
生物化学
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分子生物学
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高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2012
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IF 2.098
Shucai Liang,Hui Yu,Jin Xiang,Wang Yang,Xiaohui Chen,Yanbin Liu,Chen Gao,Guoping Yan
A new naphthalimide modified polyethylenimine (PEI) nanoparticles (called NPEI-NPs) was synthesized and applied as fluorescent probe for rapid, selective and sensitive fluorometric detection of trace DNA. The synthesis involved the covalent modification of PEI with 4-butylamino-N-carboxymethyl-1,8-naphthalimide(BACMN) for getting amphiphilic polymer. Then the amphiphilic polymer was self-assembled in water to give the NPEI-NPs. NPEI-NPs was soluble in water and emitted fluorescence at 545 nm with exciting at 460 nm. The fluorescence spectra resulting from the interaction between NPEI-NPs and DNA indicated that the fluorescence of NPEI-NPs increased in the present of DNA. Therefore, a fluorescence enhancement method was developed for the determination of trace fish sperm DNA (fsDNA) and calf thymus DNA (ctDNA). Under the optimal conditions, the calibration curves were linear over the concentration ranges of 0.05–2.8 μg/mL for fsDNA and 0.08–3.0 μg/mL for ctDNA. The detection limits for fsDNA and ctDNA were 1.6 and 2.0 ng/mL, respectively. The proposed method has been employed to quantify DNA in synthetic samples with the satisfactory results.
研究领域:
生物化学
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分析化学
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PubMed
高影响因子
MICROCHIMICA ACTA
·
2024
·Vol. 191
·期 5
·1-10
·
IF 5.3
Yao Di,Zhou Liuyan,Hu Shengqiang,Zhao Shulin,Zhang Liangliang
The sensing sensitivity was improved for silver nanoparticles (AgNPs)-based colorimetric biosensors by using the most suitable salt to induce AgNPs aggregation. As for the salt composed of low-affinity anion and monovalent cation, the cation-dependent charge screening effect was the driving force for AgNPs aggregation. Apart from the charge screening effect, both the bridging of multivalent cation to the surface ligand of AgNP and the interaction between anion and Ag contributed to inducing AgNPs aggregation. Considering the higher aggregation efficiency of AgNPs resulted in a narrower sensing range, salt composed of low-affinity anion and monovalent cation was recommended for AgNPs-based colorimetric analysis, which was confirmed by fourfold higher sensitivity of DNA-21 detection using NaF than NaCl. This work inspires further thinking on improving the sensing performance of metal nanomaterials-based sensors from the point of colloidal surface science. Graphical Abstract
研究领域:
分析化学
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纳米生物学
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PubMed
高影响因子
MICROCHIMICA ACTA
·
2025
·Vol. 192
·期 8
·1-11
·
IF 5.3
Sun Lu,Xu Qian-Yue,Wang Hai-Bo
Being enlightened by Fenton-like reaction, a novel chemically driven redox-cycling system has been developed without the participation of additional reducing agents. In this chemically driven cycling system, terephthalic acid (TA) was selected as fluorescence substrate to trap the generated hydroxyl radicals (·OH) to produce 2-hydroxyterephthalic acid (TAOH), which possessed high fluorescence intensity. On one hand, Cu + triggered a Fenton-like reaction with H 2 O 2 to yield Cu 2+ and ·OH. But on the other hand, the generated Cu 2+ could react with H 2 O 2 to produce Cu + and O 2 ·− (further converted into ·OH). The regenerated Cu + could take turns reacting with H 2 O 2 to produce more ·OH and form more TAOH. As a result, a kind of chemical redox-cycling signal amplification reaction was touched off. On the basis of copper based metal–organic frameworks (Cu-MOFs) and signal amplified strategy, a magnetic separated-mode fluorescent biosensor was designed for the sensitive determination of DNA. The method allowed ultrasensitive detection of target DNA H1N1 with a linear range from 5 pM to 10 nM, and with a limit of detection of 2 pM. This magnetic separated-type system could effectively minimize the background signals by reducing the mutual interferences between nucleic acids hybridization and fluorescence signal conversion. Graphical
研究领域:
分析化学
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生物化学
·
材料科学
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纳米技术
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生物传感器
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DNA检测
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环境科学
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PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2014
·
IF 4.517
Kao Zhu,Xianyun Hu,Qinyu Ge,Qingjiang Sun
We have developed a new fluorescent probe of thioglycolic acid (TGA)-capped CdTe quantum dots (QDs) complexed with a model drug, meso -tetrakis( N -methylpyridinium-4-yl)porphyrin (TMPyP) for detecting deoxyribonucleic acids (DNAs). This probe operates with an “Off–On” mode: TMPyP quenches the photoluminescence (PL) of QDs via a photo induced electron-transfer (PIET) process; the presence of DNA can break the QD/TMPyP complexation, interrupting the PIET process, and switch on the PL of QDs. Sensitive detection of DNA with the detection limit of 0.16 nM and a linear detection range of 0.25–6.0 nM are achieved. Importantly, this probe can be used to distinguish the binding modes of DNA–TMPyP interactions, exhibiting the DNA sequence-dependent PL recovery behaviors. The obtained binding constant for poly(dA)·poly(dT) is ∼3.30 × 10 7 L mol −1 , which is approximately one order of magnitude larger than those for native DNAs and poly(dG)·poly(dC). Furthermore, the thymine bases preferential of the TMPyP–DNA interaction is proved by this probe.
研究领域:
生物化学
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分子生物学
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PubMed
高影响因子
ANALYST
·
2014
·Vol. 139
·期 22
·5858-5867
·
IF 3.906
Yizhong Shen,Shaopu Liu,Ling Kong,Xuanping Tan,Youqiu He,Jidong Yang
Although various strategies have been reported for double-stranded DNA (DNA) detection, development of a time-saving, specific, and regeneratable fluorescence sensing platform still remains a desired goal. In this study, we proposed a new DNA detection method that relies on an “off-on” switch of a regenerated fluorescence biosensor based on an electron transfer mechanism from glutathione (GSH)-capped CdTe quantum dots (QDs) to nile blue (NB). Initially, the high fluorescence of GSH-capped CdTe QDs could be effectively quenched by NB due to the binding of NB to the GSH on the surface of the QDs and the electron transfer from the photoexcited GSH-capped CdTe QDs to NB. Then, the high affinity of DNA to NB enabled the NB to be dissociated from the surface of GSH-capped CdTe QDs to form a more stable complex with DNA and suppress the electron transfer process between GSH-capped CdTe QDs and NB, thereby restoring the fluorescence of NB surface modified GSH-capped CdTe QDs (QDs–NB). In addition, we have testified the regenerability of the proposed DNA senor. The corresponding result shows that this DNA sensor is stable for two reuses. This fluorescence “off-on” signal was sensitive to the concentration of DNA in the range from 0.0092 to 25.0 μg mL−1 with a good correlation coefficient of 0.9989, and the detection limit (3σ/S) was 2.78 ng mL−1. To further investigate for perfect analysis performance, the developed biosensor was applied for the determination of DNA in human fresh serum samples with satisfactory results.
研究领域:
生物化学
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分子生物学
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PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 2
·027501
·
IF 3.721
Wei Zhang,Jimin Yang,Di Wu
An electrochemical biosensor for direct detection of PIK3CA gene related to lung cancer was developed based on riboflavin 5'-monophosphate sodium salt (FMNs)-functionalized MoS2 nanosheets prepared by simple ultrasonication method. As a highly effective biodispersant, FMNs demonstrated excellent stabilization for obtaining highly dispersed MoS2 nanosheets in an aqueous solution. The prepared FMNs/MoS2 nanocomposite with fine electrochemical redox activity was employed as the platform to immobilize DNA probe and supplied the inherent indicator signal for DNA sensing. The amine-terminated ssDNA probe was covalently immobilized onto the FMNs/MoS2 nanocomposite with rich phosphonate groups. After the hybridization of the probe ssDNA with the complementary target DNA, the self-redox signal of the nanocomposite decreased ascribed to the changes in the conformation of DNA. The results indicated that the proposed self-signal detection platform displayed high sensitivity with a detection limit of 1.2 × 10–17 mol l−1 for PIK3CA gene from lung cancer, accompanied with fine selectivity, outstanding stability and reproducibility. The constructed biosensor was easy to design and had the potential for the detection of different pathogenic DNA without intricate label process.
研究领域:
生物医学工程
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分子生物学
·
肿瘤学
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高影响因子
BIOSENSORS & BIOELECTRONICS
·
2021
·
IF 10.618
Peng-Fei Liu,Kai-Ren Zhao,Zhi-Jun Liu,Li Wang,Shu-Ying Ye,Guo-Xi Liang
CRISPR/Cas system have drawn increasing attention in accurate and sensitive nucleic acids detection. Herein, we reported a novel Cas12a-based electrochemiluminescence biosensor for target amplification-free human papilloma virus subtype (HPV-16) DNA detection. During this detection process, Cas12a employed its two-part recognition mechanism to improve the specificity and trans-cleavage capability to achieve signal amplification , while L-Methionine stabilized gold nanoclusters (Met-AuNCs) were served as high-efficiency ECL emitters to achieve ECL signal transition. Given the unique combination of Cas12a with ECL technique, the detection limit was determined as 0.48 pM and the whole detection could be completed within 70 min. We also validated the practical application of the proposed biosensor by using undiluted human blood samples, which gives impetus to the design of new generations of CRISPR/Cas detection system beyond the traditional ones with ultimate applications in sensing analysis and diagnostic technologies.
研究领域:
生物技术
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医学诊断
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DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
·
2014
·Vol. 30
·期 4
·888-894
·
IF 3.396
Jing Hu,Xiandeng Hou,Peng Wu
Hydride generation atomic fluorescence spectrometry (HG-AFS) has been widely used for highly sensitive determination of more than 10 elements that are capable of hydride generation in geological, environmental and biological samples, but its bioanalytical potential has not been well-exploited yet. With CdS quantum dots (QDs) as both the signal labels for DNA sandwiching and analytes for HG-AFS (acid-released Cd2+ from QDs), here we proposed an ultrasensitive indirect method for HIV DNA analysis by HG-AFS. After a conventional sandwich-type hybridization reaction between capture DNA, target DNA and signal DNA labelled with CdS QD assembled silica microspheres, nitric acid was added to dissolve QDs and release Cd2+ from the QD-labels, which were then detected by HG-AFS. This efficient signal amplification strategy, coupled with the highly sensitive HG-AFS detection, gave rise to an impressive limit of detection of 0.8 aM and a wide dynamic concentration range (1 aM to 1 fM). This HG-AFS-based DNA biosensing platform holds great promise in future tumor marker detection and early cancerous diseases diagnosis.
研究领域:
生物分析化学
·
分子生物学
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高影响因子
ANALYTICAL CHEMISTRY
·
2019
·
IF 6.35
Xinfeng Zhang,Xiaoya Fan,Yanying Wang,Fengjie Lei,Lin Li,Juewen Liu,Peng Wu
Aggregation of plasmonic gold nanoparticles (AuNPs) has been widely used for label-free colorimetric sensing. Adding salt is a commonly used method to induce a color change, but salt-induced aggregation by charge screening is a slow kinetic process, making quantitative and reproducible measurement difficult. Herein, we explored an alternative method by charge neutralization using positively charged molecules, such as a DNA-staining dye, SYBR Green I (SG), for efficient and stable assembly of AuNPs. Even submicromolar SG effectively triggered the aggregation of AuNPs in less than 1 min, and the resulting intense blue color was stable for over 10 h. The charge neutralization effect of SG was confirmed with zeta potential measurements. Besides, pH-dependent aggregation of AuNPs by SG agreed well with the pKa of the nitrogen atoms responsible for the positive charges in the SG structure. Moreover, the charge neutralization effect was also observed from polycations such as polyamines. The SG-induced assembly of AuNPs was developed into a label-free colorimetric sensing platform. Benefiting from the intense blue color, this new sensing strategy allowed visual detection of as low as 0.1 nM DNA, 50-fold lower than that by salt. Such a charge neutralization strategy may inspire further thinking on fundamental colloidal science and its applications in analytical chemistry. This work itself significantly improved AuNP-based colorimetric sensors in terms of detection time, signal stability, and sensitivity.
研究领域:
分析化学
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胶体科学
·
纳米技术
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Linlin Wang,Shaopu Liu,Chenxia Hao,Xiaolong Zhang,Chaoqun Wang,Youqiu He
A dual-fluorescence “turn off–on” biosensor, which consists of quantum dots (GSH-CdTe QDs) whose fluorescence was quenched by safranine T (ST) via an electron transfer process, had been developed for herring sperm DNA (hsDNA) detection. Initially, in the “turn off” stage, the strong fluorescence of GSH-CdTe QDs could be effectively quenched by ST owing to the occurrence of the electron transfer from the photoexcited GSH-CdTe QDs to ST. And then, the high affinity of DNA to ST enabled the ST attached to the surface of GSH-CdTe QDs, to become embedded into hsDNA double helix structure to form stable complex and moved away from the QDs. Therefore, the recognition of hsDNA could be realized via the fluorescence restoration of the QDs–ST based biosensor, namely of the fluorescence “turn on” procedure. This designed biosensor exhibited good sensitivity and selectivity, for the reason that the detection limit for DNA reached 10.8 ng/mL, meanwhile, neither biologically relevant metal ions, common organic compounds, nor the amino acid had any significant interference in the detection mode. Hence, this simple, fast, sensitive, and selective biosensor owned perfect analysis applications in biochemical DNA monitoring.
研究领域:
生物化学
·
分子生物学
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高影响因子
MICROCHEMICAL JOURNAL
·
2022
·
IF 5.304
Kangyan Yi,Yi Yu,Shiyi Tan,Jinzheng Zhang,Tingyan Ye,Nannan Liu,Xingxing Tang,Lijie Zhang,Shaoming Huang
Infectious diseases, genetic diseases, and malignant tumor diseases are all related to DNA, but simple, unlabeled, and sensitive devices to detect DNA remain challenging. Carbon nanotubes biosensor has the advantages of low cost, fast detection speed, small size, and good biocompatibility. A new strategy gap device for DNA detection by using gold nanorods assembled in single-walled carbon nanotubes ( [email protected] ) was developed. The AuNRs are synthesized with an average diameter of 56 ± 4.8 nm and a length of 95 ± 9.4 nm. Because of the anisotropic physical interaction between AuNRs and SWCNTs structure, when the SWCNTs grow on the surface of SiO 2 /Si substrate, the AuNRs are self-assembled orderly. The detection principle is based on the target DNA desorbing the probe DNA on the AuNRs to change its catalytic activity. The AuNRs are connected into nanowires along with the growth of the SWCNTs, thereby generating a conductance response. By adjusting the electrode gap, different detection limits were obtained. The 0.25 μm electrode gap device detected target DNA with the detection limit of 1 pM.
研究领域:
生物传感器
·
纳米技术
·
分子生物学
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高影响因子
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