TALANTA
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2017
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IF 4.162
Lu Ding,Chunlan Xiang,Gang Zhou
Poly(acrylic acid) (PAA) brushes coated onto silica nanoparticles have been widely utilized in bioassays due to their abilities of providing favorable microenvironments and ensuring good biological activities for biomolecules. However, traditional PAA brushes are synthesized by reversible addition–fragmentation chain transfer polymerization. Hence, it is generally difficult to control and characterize the molecular weight of the PAA brushes, which may depress the reproducibility and bring more uncertain results. Herein, atom transfer radical polymerization method is employed to synthesize β -cyclodextrin-cored PAA with uniform and controllable molecular weight. After loading on the surfaces of adamantane-functionalized silica nanoparticles via host-guest interactions, glucose oxidase and probe single strand DNA (ssDNA) are further immobilized on the as-prepared nanoparticles. Meanwhile, capture ssDNA is functionalized on amino modified magnetic beads. In the presence of ssDNA sequence of Hepatitis B Virus (HBV) containing completely matched sequence of both probe and capture ssDNA, a bioconjugate is formed and can be separated by an external magnet. The isolated glucose oxidase can further catalyze glucose into gluconic acid and H 2 O 2 , and then reduce HAuCl 4 on Au seeds. By monitoring the absorption intensity change of the Au NPs at 530 nm, the proposed biosensor with novel signal amplification probes can be used to detect DNA sequence of HBV with high sensitivity and selectivity in both buffer and serum samples. This developed strategy has presented a new way to construct silica nanoparticles coated by PAA brushes for the fields of clinical diagnosis and other life sciences.
研究领域:
生物化学
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纳米医学
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临床诊断
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DOI
PubMed
高影响因子
TALANTA
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2017
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IF 4.162
Fanwei Meng,Xiaoyuan Ma,Nuo Duan,Shijia Wu,Yu Xia,Zhouping Wang,Baocai Xu
This paper investigated a new detection method of oxytetracycline (OTC) in aquatic products with ultrasensitive detection limit. The method was constructed on the basis of raman hot spot between gold nanoparticles (AuNPs) (13 nm and 80 nm diameter respectively) linked by an DNA sequence . The DNA sequence combined with the OTC aptamer including its complementary sequence as well as a stem-loop structure. The raman signal molecule (4-MBA) was modified at the surface of 13 nm AuNPs. After the exposure of OTC, the aptamer sequence was preferentially combined with OTC and partially dehybridized with its complementary sequence which led the 13 nm AuNPs to get more closer to the 80 nm AuNPs. The raman intensity was thus increased for the more enhanced hot spot generated. Under the optimal experimental conditions, the SERS signal was positively related to the OTC concentration with a wide working range of 4.60×10 −2 –4.60×10 2 fg/mL and the limit of detection (LOD) was as low as 4.35×10 −3 fg/mL. The recovery rates of fishmeal ranged from 91.29–110.98%. The specificity of this method was further examined, and the results showed that the AuNPs based aptasensor was highly selective. This developed ultrasensitive aptamer-based SERS detection platform suggested that it may be a promising strategy for a variety of sensing applications.
研究领域:
分析化学
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纳米技术
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食品科学
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环境科学
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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2022
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IF 12.545
Yanli Zhou,Jiaxiang Liu,Hui Dong,Zi Liu,Lu Wang,Qiaoxia Li,Jianhua Ren,Yintang Zhang,Maotian Xu
Interferon-gamma (IFN- γ ) is one kind of crucial inflammatory cytokines, and its expression level is closely associated with various disease progressions. This work addresses the development of a sensitive and specific electrochemical assay for detection of IFN- γ by combing the recognition unit of aptamer with the signal reporter of target-induced silver nanoclusters (AgNCs). For biosensor preparation, the gold nanoparticles (AuNPs) immobilized on the amine-terminated electrode surface provided electrochemical interfaces for the self-assembly of C-rich modified aptamers. Then, the aptamer recognized IFN- γ and the free aptamer hybridized with conjugated DNA sequences . After the nuclease-catalyzed cleavage of DNA duplex, in situ-generated AgNCs in the C-rich template was utilized as the electrochemical indicator for IFN- γ detection. The present method demonstrated a good performance for detection of IFN- γ with a low detection limit of 1.7 pg mL −1 . This aptasensor was verified to be applied for the evaluation of IFN- γ secreted by cell.
研究领域:
生物化学
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分析化学
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纳米技术
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免疫学
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DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
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2022
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IF 8.008
Jinzheng Zhang,Shuailong Zhou,Shiyi Tan,Kangyan Yi,Mengya Jin,Qian Shi,Fen Wu,Nannan Liu
Pore structure-based analytical techniques have great potential applications for the detection of biological molecules. However, the sophistication of traditional pore sensors is restricted in their applicability of analytical chemistry due to a lack of effective carrier probes. Here, we used porous coordination network-224 (PCN-224) composite probes in conjunction with a glass nanopipette (GN) as a sensing platform. The sensor exhibits a good fluorescence signal and a change in GN’s ionic current at the same time. Due to the volume exclusion mechanism coming from PCN-224, the detection limit of target DNA reaches 10 fM in a GN with a diameter of up to ca. 260 nm, outperforming a simple probe. The structure of the composite probe is optimized by the probe’s pairing efficiency. Furthermore, the sensor can also discriminate between 1-, 3-, and 5-mismatch DNA sequences and capture the target DNA from a complex mixture. Based on the GN platform, a series of techniques for detecting biomolecules are expected to emerge because of its simplicity, robustness, and universality by incorporating advanced nanoprobes.
研究领域:
分析化学
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生物传感器
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纳米技术
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分子生物学
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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2016
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IF 7.476
Yuan-Cheng Zhu,Fei Xu,Nan Zhang,Wei-Wei Zhao,Jing-Juan Xu,Hong-Yuan Chen
This work reports the use of compositionally heterogeneous asymmetric [email protected] core–satellite nanoassembly functionalized with DNA sequence as unique signaling nanoprobes for the realization of new energy-transfer-based photoelectrochemical (PEC) immunoassay of prostate- specific antigen (PSA). Specifically, the [email protected] asymmetric core–satellite nanoassemblies ( [email protected] ACS) were fabricated on a two-dimensional glass substrate by a modified controlled assembly technique, and then functionalized with DNA sequences containing PSA aptamers as signaling nanoprobes. Then, the sandwich complexing between the PSA, its antibodies, and the signaling nanoprobes was performed on a CdS QDs modified indium tin oxide (ITO) electrode. The single stranded DNA can server as a facile mediator that place the [email protected] ACS in proximity of CdS QDs, stimulating the interparticle exciton–plasmon interactions between [email protected] ACS and CdS QDs and thus quenching the excitonic states in the latter. Since the damping effect is closely related to the target concentration, a novel energy-transfer-based PEC bioanalysis could be achieved for the sensitive and specific PSA assay. The developed biosensor displayed a linear range from 1.0×10 −11 g mL −1 to 1.0×10 −7 g mL −1 and the detection limit was experimentally found to be of 0.3×10 –13 g mL −1 . This strategy used the [email protected] ACS-DNA signaling nanoprobes and overcame the deficiency of short operating distance of the energy transfer process for feasible PEC immunoassay. More significantly, it provided a way to couple the plasmonic properties of the Ag NPs and Au NPs in a single PEC bioanalytical system. We expected this work could inspire more interests and further investigations on the advanced engineering of the core–satellite or other judiciously designed nanostructures for new PEC bioanalytical uses with novel properties.
研究领域:
纳米技术
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生物化学
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分析化学
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生物物理学
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材料科学
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PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2015
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IF 6.409
Ying Zhu,Xiao-chun Hu,Shuo Shi,Ru-ru Gao,Hai-liang Huang,Yan-yan Zhu,Xiao-yan Lv,Tian-ming Yao
We report here an ultrasensitive strategy based on the recognition-induced conformational alteration of aptamer and fluorescence turn-on abilities of guanine-rich (G-rich) DNA sequence in proximity to silver nanoclusters for adenosine triphosphate (ATP), adenosine (A) and thrombin (TB) detection. Herein, we designed two tailored DNA sequences noted as complementary DNA (abbreviated as c-DNA) and signal probe DNA (abbreviated as s-DNA), respectively. c-DNA is designed as a special structure consisting of a sequence complementary to aptamer at the 3′-end and a guanine-rich DNA sequence at the 5′-end; s-DNA contains a cytosine-rich sequence responsible for Ag NCs templated synthesis at the 3′-end and a link sequence (part of aptamer) complementary to partial of the c-DNA at the 5′-end. In the presence of target, the aptamer associated with the target, resulting in the formation of duplex DNA (dsDNA), the DNA–Ag NCs thereafter could close to the guanine-rich sequence, leading to enhanced fluorescence signal readout. The widespread application of the sensing system is achieved success in the detection of three biomolecules . ATP, adenosine and thrombin in the range of 0.5-8.0 μM, 0.5-7.0 μM and 50-900 nM could be linearly detected with the detection limits of 91.6 nM, 103.4 nM and 8.4 nM, respectively. This label-free and turn-on fluorescent sensing system employing the mechanism proposed here turns out to be sensitive, selective, and convenient for the detection of biomolecules without washing and separation steps.
研究领域:
分析化学
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生物传感器
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纳米技术
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生物化学
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产品关联
DOI
PubMed
高影响因子
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