ANALYTICAL CHEMISTRY
·
2024
·
IF 6.7
Zhiyong Huang,Ziyan Du,Juan Li,Da Han,Jiaxuan He,Yunben Yang,Dan Wang,Yu Liang,Yunshan Yang,Ruizi Peng,Weihong Tan
As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection posed a significant threat to public health and the global economy, in vitro diagnosis of the SARS-CoV-2 nucleocapsid protein proved to be an effective way for SARS-CoV-2 infection control in the past years. Tyramide signal amplification (TSA) has been extensively utilized in tissue imaging and pathological diagnosis owing to the powerful signal enhancement. However, the elevated “ALWAYS ON” fluorescence background limited the accuracy and sensitivity of the conventional TSA assay. To achieve an activated “TURN ON” signal, herein, a small molecule, termed dichlorodihydrofluorescein tyramide (T-DCFH), was synthesized for activatable TSA. Under the catalysis of horseradish peroxidase (HRP) with hydrogen peroxide (H2O2), this T-DCFH facilitates the “TURN ON” fluorescence signal. Additionally, as a recognition tool, DNA aptamer has been used for developing in vitro diagnostic approaches. Hence, based on HRP-labeled aptamers binding with SARS-CoV-2 nucleocapsid protein, we achieved aptamers-based activatable TSA detection with a higher signal-to-noise ratio than that of fluorescent dye (FITC)-labeled aptamers, while showing lower background than traditional fluorescein tyramide with “ALWAYS ON”. The results demonstrated that the activated T-DCFH significantly enhances the fluorescence signal while diminishing the background noise. By employing multiple aptamers targeting, we offered a timely and accurate in vitro diagnostic approach for future emergent infectious diseases.
研究领域:
生物化学
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诊断学
·
病毒学
✓ 已验证
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2024
·
IF 4.3
Ying Zhao,Xiao-jia Li,Ji-wen Chen
Raman spectroscopy is a powerful analytical method, but when the composition of the test sample is intricate, the original spectral data may contain noise and fluorescence background interference, making it more difficult to extract Raman spectral information from the original spectra. Especially the fluorescence background signal, which is typically several orders of magnitude stronger than the Raman signal, can even overwhelm or obscure the Raman signals, thereby impeding the qualitative or quantitative analysis of the Raman spectra. One effective method for removing the fluorescence background is shift excitation Raman differential spectroscopy (SERDS), which typically involves measuring two raw Raman spectra using slightly different excitation wavelengths, combined with reconstruction algorithms, to obtain Raman spectra free from fluorescence interference. For this purpose, a reconstruction method based on Tikhonov regularized least squares (TRLS) was developed in this study, which mitigated the oscillations caused by the direct unconstrained least squares (DULS) reconstruction method. The method was verified and optimized using four groups of artificial datasets with different characteristics. By selecting an appropriate value for parameter α , the relative standard deviation (RSD) of the reconstructed datasets was lower than that of the artificial datasets in most cases. Additionally, we evaluated the performance of the TRLS reconstruction algorithm based on a quantitative model of real Raman spectral datasets, assessing the algorithm’s performance from three perspectives: the root mean square error ( RMSE ), the correlation coefficient (R), and the ratio of prediction to deviation (RPD). The quantitative results indicate that using the TRLS method for reconstruction enhances both prediction accuracy and practicality. In summary, findings from both simulated data and actual experiments demonstrate that the TRLS-based reconstruction method substantially improves the stability and reliability of differential Raman spectra reconstruction.
研究领域:
分析化学
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光谱学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Haining Li,Bing Yang,Biao Yu,Nan Huang,Lusheng Liu,Jiaqi Lu,Xin Jiang
Si nanowires always exhibited no Raman enhancement for application in surface-enhanced Raman scattering (SERS). Herein, surface modifications of Si nanowires, without the presence of noble metals, were carried out to develop biocompatible SERS substrates. The treatment of hydrogen plasma on as-prepared Si nanowires leads to no enhanced Raman signals for the absorbed R6G molecules. The coatings of nanocrystalline diamond and multilayer graphene enable Raman signals to be enhanced with a reduced fluorescent background. The graphene-coated sample exhibits a much lower fluorescent background than the diamond-coated sample at a high concentration of the dye molecules. For the sample with graphene-coated Si nanowires, the minimum detection limit is 10 -7 mol/L, and the enhancement factor reaches above 10 4 . Such stable Raman enhancement is attributed to the formation of hydrogen-terminated graphene and the presence of the nanowire structure, accelerating charger transfer between graphene and the dye molecules. Importantly, the Raman enhancement is independent of the number of graphene layers. The Raman signal remains stable after exposure to the atmosphere for one month. Therefore, a new nanostructure of Si nanowires with graphene coating is developed, which shows great potential in SERS applications.
研究领域:
材料科学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SPECTROSCOPY
·
2017
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IF 1.529
Jie Huang,Tielin Shi,Zirong Tang,Wei Zhu,Guanglan Liao,Xiaoping Li,Bo Gong,Tengyuan Zhou
We propose a bi-objective optimization model for extracting optical fiber background from the measured surface-enhanced Raman spectroscopy (SERS) spectrum of the target sample in the application of fiber optic SERS. The model is built using curve fitting to resolve the SERS spectrum into several individual bands, and simultaneously matching some resolved bands with the measured background spectrum. The Pearson correlation coefficient is selected as the similarity index and its maximum value is pursued during the spectral matching process. An algorithm is proposed, programmed, and demonstrated successfully in extracting optical fiber background or fluorescence background from the measured SERS spectra of rhodamine 6G (R6G) and crystal violet (CV). The proposed model not only can be applied to remove optical fiber background or fluorescence background for SERS spectra, but also can be transferred to conventional Raman spectra recorded using fiber optic instrumentation.
研究领域:
分析化学
·
光谱学
✓ 已验证
DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
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2013
·Vol. 36
·期 15
·2530-2537
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IF 2.591
Maria del Mar Barrios-Romero,Agustín G. Crevillén,José Carlos Diez-Masa
This work describes the development of an SDS-gel electrophoresis method for the analysis of major whey proteins (α-lactalbumin, β-lactoglobulin, and BSA) carried out in SU-8 microchips. The method uses a low-viscosity solution of dextran as a sieving polymer. A commercial coating agent (EOTrol LN) was added to the separation buffer to control the EOF of the chips. The potential of this coating agent to prevent protein adsorption on the walls of the SU-8 channels was also evaluated. Additionally, the fluorescence background of the SU-8 material was studied to improve the sensitivity of the method. By selecting an excitation wavelength of 532 nm at which the background fluorescence remains low and by replacing the mercury arc lamp by a laser in the detection system, an LOD in the nanomolar range was achieved for proteins derivatized with the fluorogenic reagent Chromeo P540. Finally, the method was applied to the analysis of milk samples, demonstrating the potential of SU-8 microchips for the analysis of proteins in complex food samples.
研究领域:
分析化学
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蛋白质组学
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食品分析
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微流控技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）