Materials
·
2022
·Vol. 16
·期 1
·387
·
IF 3.748
Kezhu Xu,Qunling Fang,Jing Wang,Ailing Hui,Shouhu Xuan
Due to the abuse of antibiotics, the sensitivity of patients to antibiotics is gradually reduced. This work develops a Fe3O4@SiO2@Au/PDA nanochain which shows an interesting magnetic-field-induced improvement of its photothermal antibacterial property. First, SiO2was wrapped on Fe3O4nanospheres assembled in a chain to form a Fe3O4@SiO2nanocomposite with a chain-like nanostructure. Then, the magnetic Fe3O4@SiO2@Au/PDA nanochains were prepared using in situ redox-oxidization polymerization. Under the irradiation of an 808 nm NIR laser, the temperature rise of the Fe3O4@SiO2@Au/PDA nanochain dispersion was obvious, indicating that they possessed a good photothermal effect. Originating from the Fe3O4, the Fe3O4@SiO2@Au/PDA nanochain showed a typical soft magnetic behavior. Both the NIR and magnetic field affected the antimicrobial performance of the Fe3O4@SiO2@Au/PDA nanochains.Escherichia coliandStaphylococcus aureuswere used as models to verify the antibacterial properties. The experimental results showed that the Fe3O4@SiO2@Au/PDA nanochains exhibited good antibacterial properties under photothermal conditions. After applying a magnetic field, the bactericidal effect was further significantly enhanced. The above results show that the material has a broad application prospect in inhibiting the growth of bacteria.
研究领域:
材料科学
·
生物医学工程
·
微生物学
✓ 已验证
DOI
高影响因子
Chemosensors
·
2023
·Vol. 11
·期 6
·347
·
IF 4.2
Chao Liu,Hui Wang,Shengmin Xu,Hongbao Li,Yilin Lu,Chuhong Zhu
Mercury ions can be enriched along the food chain and even low concentrations of mercury ions can seriously affect human health and the environment. Therefore, rapid, sensitive, and highly selective detection of mercury ions is of great significance. In this work, we synthesized Fe3O4@SiO2@Au three-layer core/shell nanoparticles, and then modified 4-MPy (4-mercaptopyridine) to form a SERS sensor. Mercury ions in water can be easily captured by 4-MPy which were used as the reporter molecules, and the concentration of mercury ions can be evaluated based on the spectral changes (intensification and reduction of peaks) from 4-MPy. After the mercury ion was combined with the pyridine ring, the peak intensity at 1093 cm−1increased with the concentration of mercury ion in the range of 10 ppm–1 ppb, while the Raman intensity ratio I (416 cm−1)/I (436 cm−1) decreased with the increase of mercury ion concentration. This magnetically separatable and recyclable SERS sensor demonstrates good stability, accuracy, and anti-interference ability and shows the potential to detect actual samples. Furthermore, we demonstrate that the probe is applicable for Hg2+imaging in macrophage cells.Keywords:core/shell nanoparticles;4-pyridinethiol;surface-enhanced Raman spectroscopy (SERS);Mercury (II) ion;Raman cell imaging
研究领域:
纳米技术
·
分析化学
·
环境科学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Applied Spectroscopy
·
2018
·Vol. 85
·期 1
·160-165
·
IF 0.611
Neng Jing,Wang Xujun,Jia Kan,Sun Peilong
Fe 3 O 4 nanoparticles were first modified with tetraethoxylsilane to form Fe 3 O 4 /SiO 2 nanoparticles, followed by the addition of 3-aminopropyltriethoxysilane and 3-thiolpropyltriethoxysilane to introduce –NH 2 and –SH groups to the surface of Fe 3 O 4 /SiO 2 nanoparticles. Gold nanoparticles were further assembled on the surface of Fe 3 O 4 /SiO 2 via the electrostatic adsorption of –NH 2 and the Au–S bond to produce stable core–shell Fe 3 O 4 /SiO 2 /Au gold/magnetic nanoparticles. These Fe 3 O 4 /SiO 2 /Au gold/magnetic nanoparticles were characterized by a variety of techniques such as transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX), and afterwards conjugated with tetrodotoxin antibodies (Ab) and used as a Raman active substrate (Fe 3 O 4 /SiO 2 /Au–Ab) with Rhodamine B (RhB)-labeled tetrodotoxin antibody as a Raman reporter (Ab–RhB). Upon mixing these reagents with tetrodotoxin (TTX), a sandwich complex [Fe 3 O 4 /SiO 2 /Au–Ab···TTX···Ab–RhB] was generated due to the specific antibody–antigen interactions. The immunocomplex was subsequently separated by an externally applied magnetic source and concentrated into a pellet point, where the laser interrogation of the pellet produced a strong signal characteristic of RhB. The logarithmic intensity of the signal was found to be proportional to the concentration of TTX with a limit of detection of 0.01 μg/mL and a detection linearity range of ~ 0.01–0.5 μg/mL. The established method eliminates the complicated procedures of traditional centrifuging, column separation, and incubation and achieves a rapid detection of tetrodotoxin with improved detection sensitivity.
研究领域:
分析化学
·
纳米技术
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
E-POLYMERS
·
2022
·Vol. 22
·期 1
·488-504
·
IF 3.074
Fangsheng Wu,Zihua Zhang,Wei Liu,Yuan Liu,Xiujuan Chen,Pingyong Liao,Qiaoying Han,Lun Song,Hong Chen,Wenbin Liu
In this study, a novel material of core–shell structured magnetic molecularly imprinted polymers (Fe 3 O 4 @SiO 2 @Au (FSA)-MIPs) was successfully prepared for the rapid and selective determination of 4-methylmethcathinone (mephedrone, 4-MMC). The adsorption capacity of FSA-MIPs is 34.7 mg·g −1 at 308 K, which is significantly higher than magnetic non-imprinted polymers profiting from the imprinting effect. The FSA-MIPs have a short equilibrium (20 min) and could be reused more than six times. Moreover, the selectivity coefficients of FSA-MIPs for 4-MMC, 3,4-dimethylmethcathinone, butylone, 4-ethylmethcathinone, acetylfentanyl, and methylene blue are 4.01, 5.65, 7.62, 12.30, and 20.87 respectively, further indicating the markedly enhanced binding selectivity of FSA-MIPs. As an adsorbent, the FSA-MIPs were successfully applied for effective extraction of 4-MMC in three human urine samples with the recovery rates ranging from 85.5–92.6%. The results confirmed that the FSA-MIPs have good prospects in the extraction and separation of synthetic cathinones, which is suitable for further application in the criminal sciences field.
研究领域:
分析化学
·
法医学
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2024
·
IF 6.7
Xunlong Ji,Hui Chen,Zijin Hong,Jingjing Du,Zhenli Sun
Accurate measurement of aerosol pH is crucial for understanding atmospheric processes and mitigating haze pollution. However, online detection of aerosol pH is challenging due to the complex composition of single-particle matter and trace components. This study develops a sensitive and selective sensor for the online detection of aerosol pH using surface-enhanced Raman spectroscopy (SERS). A novel Fe3O4@SiO2@Au-p-aminothiophenol (FA-pATP) sensor was fabricated using a layer-by-layer self-assembly method, achieving enhanced uniformity and increased density of SERS-active hotspots. Magnetic aggregation was employed to further amplify the Raman signal. This sensor was integrated into a 3D-printed microfluidic device to facilitate online monitoring of aerosol pH. The FA-pATP sensor exhibited a significant increase in peak intensity ratio with rising pH, demonstrating high sensitivity and responsiveness due to structural changes in the −NH2 groups of pATP under different pH conditions. The sensor demonstrated a linear pH response ranging from 5 to 11. The 3D-printed microfluidic device, coupled with the FA-pATP sensor, demonstrated notable performance in various environmental media, indicating strong anti-interference capabilities. The proposed sensor shows great promise for real-time online monitoring of aerosol pH, with broad applications in environmental monitoring.
研究领域:
环境科学
·
分析化学
·
材料科学
·
大气化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2014
·Vol. 6
·期 23
·14360-14370
·
IF 6.739
Xiulong Jin,Haiyan Li,Shanshan Wang,Ni Kong,Hong Xu,Qihua Fu,Hongchen Gu,Jian Ye
With the increasing need for multi-purpose analysis in the biomedical field, traditional single diagnosis methods cannot meet the requirements. Therefore new multifunctional technologies and materials for the integration of sample collection, sensing and imaging are in great demand. Core–shell nanoparticles offer a unique platform to combine multifunctions in a single particle. In this work, we have constructed a novel type of core–shell superparamagnetic nanoshell (Fe3O4@SiO2@Au), composed of a Fe3O4 cluster core, a thin Au shell and a SiO2 layer in between. The obtained multifunctional nanoparticles combine the magnetic properties and plasmonic optical properties effectively, which were well investigated by a number of experimental characterization methods and theoretical simulations. We have demonstrated that Fe3O4@SiO2@Au nanoparticles can be utilized for two-photon luminescence (TPL) imaging, near-infrared surface-enhanced Raman scattering (NIR SERS) and cell collection by magnetic separation. The TPL intensity could be further greatly enhanced through the plasmon coupling effect in the self-assembled nanoparticle chains, which were triggered by an external magnetic field. In addition, Fe3O4@SiO2@Au nanoparticles may have great potential applications such as enhanced magnetic resonance imaging (MRI) and photo-thermotherapy. Successful combination of multifunctions including magnetic response, biosensing and bioimaging in single nanoparticles allows further manipulation, real-time tracking, and intracellular molecule analysis of live cells at a single-cell level.
研究领域:
生物医学工程
·
纳米技术
·
材料科学
·
分子生物学
·
成像科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 28
·17151-17157
·
IF 10.7
Zhenli Sun,Ning Wang,Yiyan Zhang,Xunlong Ji,Zijin Hong,Dan Xie,Wentao Zhang,Wenjing Liu,Jingjing Du
Surface-enhanced Raman scattering (SERS) is a pivotal analytical technique in sensing, yet it grapples with challenges such as reproducibility, substrate stability, and hotspot uniformity. The use of highly effective external field nanocomposites facilitates the dynamic manipulation of “hotspots”—the nanoscale gaps between metal nanoparticles—which is critical for SERS enhancement. The gap between 4-mercaptopyridine-modified (4-MPY) Fe3O4@SiO2@Au nanocomposites (FA) can be precisely reduced by applying an external magnetic field, resulting in up to a 30-fold increase in SERS signal intensity and an 8–39 times increase in the enhancement factor (EF). This approach markedly enhances SERS signal uniformity, demonstrated by the relative standard deviation of the EF dropping from 59.15–9.44% to 28.70–1.14%. By systematically studying the correlations between the SERS EF and the external-magnetic-field strength, hotspot density, and probe molecular density, sensitive magnetic, SERS platforms are established. The optimal hotspots occur in the magnetic field of 80 to 120 mT among the FA-4MPY nanocomposites, as validated by COMSOL finite-element analysis simulations. These findings offer a nuanced understanding of magnetic SERS hotspot tuning, paving the way for precise and improved molecular sensing.
研究领域:
分析化学
·
纳米技术
·
材料科学
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）