TALANTA
·
2025
·
IF 6.1
Li Zheng,Fan Sun,Qingdan Ye,Mengmeng Wang,Pei Liang,Qiang Chen,Kun Pang,Yufeng Wang
Rapid, accurate, and broad-spectrum detection of pathogenic bacteria in food is very important and an emerging need for increasing food safety concerns. Here, we present an ultrasensitive Surface-enhanced Raman spectroscopy (SERS) based aptasensor, which consists of core-shell structure (Ag@Au) and magnetic composites (Fe 3 O 4 @Au@Ag). 4-mercaptobenzoic acid (4MBA) as Raman reporter was embedded in Ag@Au nanoparticles (Ag@4MBA@Au) based on an internal standard. The combination of Ag@4MBA@Au and Fe 3 O 4 @Au@Ag are used to form the aptasensor with strongest Raman signal. Upon exposure to salmonella, the interaction between the SERS nanotags and the magnetic substrate was disrupted, causing an inverse correlation between the Raman intensity of 4MBA and the salmonella concentration. The result shows a wide linear range from 10 to 10 8 cfu/mL with five subtypes salmonella (S. Typhimurium, S. Enteritidis, S. Kentucky, S. Indiana, S. NO) and a low limit of detection of 1.782, 1.637, 1.941, 1.632, 1.875 cfu/mL, respectively. When applied to the detection of salmonella in actual samples (lake water, milk, shrimp), no pretreatment is required, and the results show no significant difference compared to the standard.
研究领域:
食品安全
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分析化学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2021
·Vol. 17
·期 25
·2100862
·
IF 13.281
Liang Huang,Yuxing Zhang,Tao Liao,Kui Xu,Chenxing Jiang,Dinglv Zhuo,Yang Wang,Hui-Min Wen,Jing Wang,Lijiao Ao,Jun Hu
Exploring signal amplification strategies to enhance the sensitivity of lateral flow immunoassay (LFIA) is of great significance for point-of-care (POC) testing of low-concentrated targets in the field of in vitro diagnostics. Here, a highly-sensitive LFIA platform using compact and hierarchical magneto–fluorescent assemblies as both target-enrichment substrates and optical sensing labels is demonstrated. The large-pored dendritic templates are utilized for high-density incorporation of both superparamagnetic iron oxide nanoparticles (IOs) and quantum dots (QDs) within the vertical channels. The hierarchical structure is built via affinity-driven assembly of IOs and QDs from organic phase with silica surface and mercapto-organosilica intermediate layer, respectively. The sequential assembly with central–radial channels enables 3D loading of dual components and separately controlling of discrete functionalities. After the alkyl-organosilica encapsulation and silica sealing, the composite spheres exhibit high stabilities and compatibility with LFIA for procalcitonin (PCT) detection. With the assistance of liquid-phase antigen-capturing, magnetic enrichment, and fluorescence-signal amplification, a limit of detection of 0.031 ng mL −1 for PCT is achieved with a linear range from 0.012 to 10 ng mL −1 . The current LFIA is robust and validated for PCT detection in real serum, which holds great diagnostic significance for precise guidance of antibiotic therapy with POC manner.
研究领域:
即时检测
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体外诊断
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纳米技术
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生物工程
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
·
IF 3.232
Zi Hao Li,Jia Hao Bai,Xin Zhang,Jia Meng Lv,Cheng Shan Fan,Yong Mei Zhao,Zheng Long Wu,Hai Jun Xu
A facile method for synthesizing Au nanoparticle-coated Fe 3 O 4 magnetic composite nanospheres (Fe 3 O 4 @Au MCS) via seed-mediated growth and iterative reduction is reported. The nanospheres were then successfully used to detect malachite green (MG) residues in water bodies via surface-enhanced Raman scattering (SERS) technique. Fe 3 O 4 @Au MCS has excellent optical properties and superparamagnetism ; it can be dispersed into the solution to fully adsorb target molecules and then collected with a magnet to increase the molecular density and the number of SERS hot spots. Magnetic enrichment was superior to conventional detection method. The limit of detection for MG was 10 −7 M and the enhancement factor was 1.1 × 10 5 . The logarithm of the SERS intensity of the characteristic peak at 1618 cm −1 exhibited a linear relationship with the logarithm of the MG concentration over the range of 10 −3 – 10 −7 M, with a correlation coefficient of 0.966. The Fe 3 O 4 @Au MCS had good uniformity of SERS signals, with a 18.59% relative standard deviation for the SERS intensity. MG detection in aquaculture water conformed with the established quantitative regulations. The SERS spectrum calculated with density function theory for MG adsorbed on Fe 3 O 4 @Au MCS was very close to the experimental spectrum, which verified enhancement by the substrate. Overall, Fe 3 O 4 @Au MCS enabled ultrasensitive, quantitative SERS detection of MG.
研究领域:
纳米技术
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分析化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Yingnan Liu,Zhirong Guo,Fan Li,Yaqing Xiao,Yalan Zhang,Tong Bu,Pei Jia,Taotao Zhe,Li Wang
Synergistic therapeutic strategies for bacterial infection have attracted extensive attentions owing to their enhanced therapeutic effects and less adverse effects compared with monotherapy. Herein, we report a novel synergistic antibacterial platform that integrates the nanocatalytic antibacterial therapy and photothermal therapy (PTT) by hemoglobin-functionalized copper ferrite nanoparticles (Hb-CFNPs). In the presence of a low concentration of hydrogen peroxide (H2O2), the excellent Fenton and Fenton-like reaction activity of Hb-CFNPs can effectively catalyze the decomposition of H2O2 to produce hydroxyl radicals (·OH), rendering an increase in the permeability of the bacterial cell membrane and the sensitivity to heat. With the assistance of NIR irradiation, hyperthermia generated by Hb-CFNPs can induce the death of the damaged bacteria. Additionally, owing to the outstanding magnetic property of Hb-CFNPs, it can improve the photothermal efficiency by about 20 times via magnetic enrichment, which facilitates to realize excellent bactericidal efficacy at a very low experimental dose (20 μg/mL). In vitro antibacterial experiment shows that this synergistic antibacterial strategy has a broad-spectrum antibacterial property against Gram-negative Escherichia coli (E. coli, 100%) and Gram-positive Staphylococcus aureus (S. aureus, 96.4%). More importantly, in vivo S. aureus-infected abscess treatment studies indicate that Hb-CFNPs can serve as an antibacterial candidate with negligible toxicity to realize synergistic treatment of bacterial infections through catalytic and photothermal effects. Accordingly, this study proposes a novel, high-efficiency, and multifunctional therapeutic system for the treatment of bacterial infection, which will open up a new avenue for the design of synergistic antibacterial systems in the future.
研究领域:
材料科学
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纳米技术
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生物医学工程
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抗菌研究
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光热疗法
·
药物递送系统
✓ 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）