FOOD CHEMISTRY
·
2019
·
IF 5.399
Bin Wang,Jiushang Zheng,Ailing Ding,Liqun Xu,Jiuncun Chen,Chang Ming Li
A novel aptasensor, based on a perylene probe (PAPDI; N,N′-bis(propylenetrimethylammonium)-3,4,9,10-perylenediimide), was developed for the detection of aflatoxin B1 (AFB1) in maize samples. AuNPs/DNA composites were synthesized and integrated with aptamers-modified magnetic nanoparticles (MNPs) via DNA hybridization. For AFB1 determination, AuNPs/DNA composites were released from MNPs through specific binding of AFB1 with the aptamer and used for assembly of the PAPDI probe. To enhance the method sensitivity, terminal deoxynucleotidyl transferase (TdT)-catalyzed DNA polymerization was performed to elongate DNA on AuNPs/DNA composites. As a result, more PAPDI probes were assembled on the AuNPs/DNA composites. Through a multiple signal amplification strategy, the proposed method exhibited high sensitivity towards AFB1, with a detection limit of 0.01 nM (3.1 pg/mL). In summary, the proposed method has great potential to be a universal strategy for monitoring AFB1 in food samples.
✓ 已验证
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Xiao Fang Zhang,Na Li,Yu Ling,Nian Bing Li,Hong Qun Luo
Since uracil-DNA glycosylase (UDG) is closely related to some human diseases, monitoring and detection of UDG activity have great significance in its clinic diagnosis and functional study. Here we demonstrate a sensitive cascade multi-amplification fluorescence strategy for the active UDG assay with the help of exonuclease III (Exo III). Under the cleavage reaction of UDG, the double-stranded DNA containing peculiar uracil bases separated into two dissociative single-stranded DNA, which separately hybridized with two cyclic hairpin probes to launch the Exo III-assisted dual cycles. The hairpin DNA modified with fluorophore and quenching group was employed as the signal probe. After the dual cycles, countless same short DNA fragments were generated to hybridize with signal probes, initiating a new Exo III-assisted cyclic amplification and releasing numerous single-stranded DNA which carried only fluorophores. Thus, the fluorescence intensity of the detection system was enhanced. This study obtained the detection limit as low as 2.4 × 10 −4 U/mL for detecting the UDG activity. And it performed satisfactory selectivity and well practical applicability by analysis of the HeLa cell lysate, providing a potential method for clinic diagnosis and functional study of UDG activity.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2017
·Vol. 185
·期 1
·1-7
·
IF 4.58
Wang Jun,Ma Kui,Yin Huanshun,Zhou Yunlei,Ai Shiyun
An aptamer based method is described for the electrochemical determination of ampicillin. It is based on the use of DNA aptamer, DNA functionalized gold nanoparticles (DNA-AuNPs), and single-stranded DNA binding protein (ssDNA-BP). When the aptamer hybridizes with the target DNA on the AuNPs, the ssDNA-BP is captured on the electrode surface via its specific interaction with ss-DNA. This results in a decreased electrochemical signal of the redox probe Fe(CN) 6
3− which is measured best at a voltage of 0.188 mV (vs. reference electrode). In the presence of ampicillin, the formation of aptamer-ampicillin conjugate blocks the further immobilization of DNA-AuNPs and ssDNA-BP, and this leads to an increased response. The method has a linear reposne that convers the 1 pM to 5 nM ampicillin concentration range, with a 0.38 pM detection limit (at an S/N ratio of 3). The assay is selective, stable and reproducible. It was applied to the determination of ampicillin in spiked milk samples where it gave recoveries ranging from 95.5 to 105.5%.
Schematic of a simple and sensitive electrochemical apta-biosensor for ampicillin detection. It is based on the use of gold nanoparticles (AuNPs), DNA aptamer, DNA functionalized AuNPs (DNA-AuNPs), and single-strand DNA binding protein (SSBP).
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2017
·
IF 4.162
Jing Zhu,Qijie Hao,Yi Liu,Zhaohui Guo,Buayxigul Rustam,Wei Jiang
The detection of uracil-DNA glycosylase (UDG) activity is pivotal for its biochemical studies and the development of drugs for UDG-related diseases. Here, we explored an integrated DNA structure switch for high sensitive detection of UDG activity. The DNA structure switch containing two branched hairpins was employed to recognize UDG enzyme and generate fluorescent signal. Under the action of UDG, one branched hairpin was impelled folding into a close conformation after the excision of the single uracil . This reconfigured hairpin could immediately initiate the polymerization/nicking amplification reaction of another branched hairpin accompanying with the release of numerous G-quadruplexes (G4s). In the absence of UDG, the DNA structure switch kept its original configuration, and thus the subsequent polymerization/nicking reaction was inhibited, resulting in the release of few G4 strands. In this work, Thioflavin T was used as signal reporter to target G4s. By integrating the DNA structure switch, the quick response and high sensitivity for UDG determination was achieved and a low detection limit of 0.0001 U/mL was obtained, which was superior to the most fluorescent methods for UDG assay. The repeatability of the as-proposed strategy was demonstrated under the concentration of 0.02 U/mL and 0.002 U/mL, the relative standard deviation obtained from 5 successive samples were 1.7% and 2.8%, respectively. The integrated DNA structure switch strategy proposed here has the potential application for the study of mechanism and function of UDG enzyme and the screening the inhibitors as potential drugs and biochemical tools.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2022
·
IF 6.556
Chuiyu Zhu,Xiao Tian,Qiuyan Li,Zichang Dai,Lina Wang,Huamin Liu,Chenghong Li,Kashif Rafiq Zahid,Chunmei Wu,Hui Huang,Lichao Fang,Qiyuan Huang,Feixue Liu,Jun Deng,Yan Li,Tao Zeng,Junsong Zheng
Altered DNA methylation in the form of 5-methylcytosine (5-mC) patterns is correlated with disease diagnosis, prognosis, and treatment response. Therefore, accurate analysis of 5-mC is of great significance for the diagnosis of diseases. Here, an efficient enhanced photoelectrochemical (PEC) biosensor was designed for the quantitative analysis of DNA 5-mC based on a cascaded energy level aligned co-sensitization strategy coupling with the bridged DNA nanoprobe (BDN). Firstly, Au nanoparticle/graphite phase carbon nitride/titanium dioxide (AuNPs/g-C 3 N 4 @TiO 2 ) nanocomposite was synthesized through in situ growth of AuNPs on g-C 3 N 4 @TiO 2 surface as a matrix to provide a stable background signal. Next, BDN with a high mass transfer rate synthesized from a pair of DNA tetrahedral as nanomechanical handles was used as a capture probe to bind to the target sequence. The polydopamine nanosphere was applied to load with CdTe QDs (PDANS-CdTe QDs) as a photocurrent label of 5-mC antibodies. When the 5-mC existed, a large number of PDANS-Ab-CdTe QDs were introduced to the electrode surface, the formed CdTe QDs/AuNPs/g-C 3 N 4 @TiO 2 co-sensitive structure could effectively enhance the electron transfer capability and photocurrent response rate due to the effective cascade energy level arrangement, leading to a significantly enhanced photocurrent signal. The proposed PEC biosensor manifested a wide range from 10 −17 M to 10 −7 M and a detection limit of 2.2 aM. Meanwhile, the excellent performance indicated the practicability of the designed strategy, thus being capable of the clinical diagnosis of 5-mC.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Xiaoyan Zhang,Tingting Wu,Yuemeng Yang,Yongqiang Wen,Shutao Wang,Li-Ping Xu
Superwettable microchips exhibit excellent ability to anchor microdroplets and great potential in ultratrace sample detection. Herein, we present a superwettable electrochemical biosensor based on a dual-DNA walker strategy (dual-DW biosensor) for the attomolar detection of food-borne microorganisms ssDNA in microdroplets. In the presence of the target E. coli O157: H7 ssDNA, the blocked walking probe is activated as the first-step DNA walker. With the aid of the Nt.BsmAI nicking endonuclease, the partial sequence of the basal probe was released, thus achieving the first-step signal amplification. Then the hairpin probe 1(H1) was opened by the released basal probe and followed by the autonomous strand displacement of the ferrocene (Fc) labeled hairpin probe 2 (H2) and movement of the basal probe. Under optimized conditions, the dual-DNA walker strategy finally renders the dual-DW biosensor an ultrahigh sensitivity of 30 aM toward E. coli O157: H7 ssDNA and a broad detection linear range. The dual-DW biosensor also enables successful analysis of trace amount of E. coli O157: H7 ssDNA in real food samples. The superwettable electrochemical biosensor based on a dual-DNA walker strategy is expected to be a versatile tool for ultratrace DNA detection and be promising in food analysis.
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2014
·
IF 4.517
Zhenning Xu,Huanshun Yin,Yunxiang Han,Yunlei Zhou,Shiyun Ai
In this work, a novel electrochemical protocol with signal amplification for determination of DNA methylation and methyltransferase activity using DNA-based hybridization chain reaction (HCR) was proposed. After the gold electrode was modified with dsDNA, it was treated with M. Sss I MTase, H pa II endonuclease, respectively. And then the HCR was initiated by the target DNA and two hairpin helper DNAs, which lead to the formation of extended dsDNA polymers on the electrode surface. The signal was amplified by the labeled biotin on the hairpin probes. As a result, the streptavidin-alkaline phosphatase (S-ALP) conjugated on the electrode surface through the specific interaction between biotin and S-ALP. ALP could convert 1-naphthyl phosphate into 1-naphthol and the latter could be electrochemically oxidized, which was used to monitor the methylation event and MTase activity. The HCR assay presents good electrochemical responses for the determination of M. Sss I MTase at a concentration as low as 0.0067 unit mL −1 . Moreover, the effects of anti-cancer drug and environmental phenolic hormone on M. Sss I MTase activity were also investigated. The results indicated that 5-fluorouracil and daunorubicin hydrochloride could inhibit the activity, and the opposite results were obtained with bisphenol A and nonylphenol. Therefore, this method can not only provide a platform to screen the inhibitors of DNA MTase and develop new anticancer drugs, but also offer a novel technique to investigate the possible carcinogenesis mechanism.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
·
2024
·Vol. 121
·期 34
·e2410164121
·
IF 9.4
Kunjie Li,Xiaoyun Lu,Jiaqi Liao,Heng Chen,Wei Lin,Yuhan Zhao,Dongbao Tang,Congyu Li,Zhenyang Tian,Zhi Zhu,Huifeng Jiang,Jun Sun,Huimin Zhang,Chaoyong Yang
In the age of information explosion, the exponential growth of digital data far exceeds the capacity of current mainstream storage media. DNA is emerging as a promising alternative due to its higher storage density, longer retention time, and lower power consumption. To date, commercially mature DNA synthesis and sequencing technologies allow for writing and reading of information on DNA with customization and convenience at the research level. However, under the disconnected and nonspecialized mode, DNA data storage encounters practical challenges, including susceptibility to errors, long storage latency, resource-intensive requirements, and elevated information security risks. Herein, we introduce a platform named DNA-DISK that seamlessly streamlined DNA synthesis, storage, and sequencing on digital microfluidics coupled with a tabletop device for automated end-to-end information storage. The single-nucleotide enzymatic DNA synthesis with biocapping strategy is utilized, offering an ecofriendly and cost-effective approach for data writing. A DNA encapsulation using thermo-responsive agarose is developed for on-chip solidification, not only eliminating data clutter but also preventing DNA degradation. Pyrosequencing is employed for in situ and accurate data reading. As a proof of concept, DNA-DISK successfully stored and retrieved a musical sheet file (228 bits) with lower write-to-read latency (4.4 min of latency per bit) as well as superior automation compared to other platforms, demonstrating its potential to evolve into a DNA Hard Disk Drive in the future.
研究领域:
合成生物学
·
生物信息学
·
分子数据存储
·
微流控技术
·
生物技术
✓ 已验证
DOI
高影响因子
Toxics
·
2026
·Vol. 14
·期 4
·341
·
IF 4.9
Xin Liu,Zhiyuan Han,Kuibin Han,Yuhan Pang,Xiaoyue Zhao,Yuting Wang,Xiaoyan Wu,Tuanwei Wang
Lead (Pb) and cadmium (Cd) are common environmental pollutants. Our previous population study revealed a significant positive association between Pb and Cd exposure and the micronuclei frequency among lead smelting workers. However, the underlying mechanisms remain unclear. In this study, human lymphoblastoid TK6 cells were used to investigate the genotoxicity and its mechanisms induced by individual or combined exposure to Pb and Cd. Our results showed that Pb and Cd exposure, alone or in combination, triggered oxidative stress, as evidenced by reduced antioxidant enzyme activity (GSH, SOD and CAT) and increased content of ROS and GSSG. Both metals induced pronounced DNA damage, as shown by elevated Tail DNA% in the Comet assay and γ-H2AX fluorescence intensity. Furthermore, Pb and/or Cd exposure caused inhibition of the DNA repair proteins, including BRCA1, CtIP, RAD52, and XRCC2, indicating impaired DNA repair capacity; and upregulated Bax expression and the Bax/Bcl-2 ratio and Caspase-3 with downregulation of Bcl-2. Notably, Pb and Cd co-exposure produced an antagonistic effect, modulating oxidative stress indicators, cell-cycle arrest, DNA damage markers, DNA repair and apoptosis-related proteins. These findings demonstrate that Pb and Cd induce oxidative stress, DNA damage, inhibition of DNA repair, and apoptosis in TK6 cells. Our study provides new insights into the mechanisms of heavy metal combined exposure–induced genotoxicity and identifies potential molecular targets for intervention.
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF FOOD ENGINEERING
·
2023
·
IF 5.5
Chuye Ji,Muhammad Aslam Khan,Kaiwen Chen,Li Liang
Zein particles are potential for the encapsulation of bioactive compounds . Deoxyribonucleic acid (DNA) shows good pH stability and can complex with antioxidants. In this study, DNA and DNA-quercetin complexes was used as the coating layer of zein particles. Zein particles had a size of 85.10 nm and ζ-potential of −30.73 mV at 1 mg/mL DNA. Zein/DNA particles were stable at pH 4–9. Encapsulation efficiency of kaempferol and α-tocopherol in complex particles reached 92.90% and 97.02%, respectively. The potential use of zein/DNA particles was evaluated for protecting kaempferol. Moreover, DNA-quercetin complex coating was investigated to discuss the protection of α-tocopherol in zein particles. The DNA coating improved the storage stability of kaempferol or α-tocopherol by strengthening physical barrier. DNA-quercetin complexes further improved the stability of α-tocopherol by acting as antioxidant barrier. The retention of kaempferol and α-tocopherol was about 58% in zein/DNA and zein/DNA-quercetin particles at 45 °C after 28 days.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2023
·
IF 7.4
Baoting Dou,Hui Zhou,Xiguang Han,Po Wang
The dissociation of the walking strand from the track gives rise to decreased efficiency and long reaction time of DNA walkers. In this work, we constructed a DNA walker combining the introduction of a wedge segment with a bimetallic metal–organic framework (MOF) electrocatalyst to solve this problem. The target methylated DNA acted as a single-legged walker, and the immobilization probe assembled on the track contained a wedge segment that was complementary to the target methylated DNA persistently, inhibiting its dissociation from the track. The fuel strand modified with a bimetallic MOF would drive the target strand to conduct branch migration and move processively along the track. The stepwise movement of the target strand resulted in the loading of numerous bimetallic MOF catalysts to reduce H2O2 at the electrode interface, thereby a significantly increased current response would be obtained for the detection of methylated DNA. This DNA walker achieved a detection limit of 200 aM within 20 min and effectively distinguished DNA with different methylation statuses, which would pave a way for rapid and sensitive monitoring of DNA methylation.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Biomedical Nanotechnology
·
2018
·Vol. 14
·期 1
·150-160
·
IF 5.068
Li Taotao,Yi Huan,Liu Yuan,Wang Zunliang,Liu Shiquan,He Nongyue,Liu Hongna,Deng Yan
DNA strands have been used as templates to form different sized silver nanoclusters. Although DNA templated silver nanoclusters (NCs) probes which show outstanding fluorescence properties have been widely applied in chemical sensing and cellular imaging, synthesis of DNA template Au–Ag
bimetallic nanoclusters remains a challenge. A facile one-step synthesis method was thus developed in this study to form Au–Ag NCs using C4-ATAT-C4 as template. C4-ATAT-C4 acted as a stabilizer for preventing aggregation of the Au–Ag NCs. The obtained Au–Ag NCs stabilized
by C4-ATAT-C4 showed bright fluorescence and high stability. A series of experiments showed that temperature, citrate-citric acid buffer, sequence and concentration of DNA played an important role in the synthesis of fluorescent Au–Ag NCs. In addition, a ratiometric fluorescence probe
was designed through combining the nucleotide sequence (C4-ATAT-C4) and hybridization sequence in the presence of the double-strand-chelating dye Super SYBR Green (SG). The combination of prepared Au–Ag NCs, Super SG, and perfectly matched DNA emitted fluorescence at 500 and 590 nm,
respectively, when the composite was excited at 290 nm. A gastric cancer gene was also selectively detected by our developed ratiometric fluorescence probe.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）