SENSORS AND ACTUATORS B-CHEMICAL
·
2023
·
IF 8.4
Zhihao Feng,Xiaoyi Li,Changxiang Fang,Junying Li,Rongfei Wang,Weihua Hu
Oblique-incidence reflectivity difference (OIRD) is a newly established method to monitor various surface processes and shows great prospect for real-time and label-free immunoassay , yet its sensitivity needs essential improvement to meet the requirement of practical applications. In this work, a label-free OIRD immunoassay biochip was developed with improved sensitivity by using standard glass slide coated with polystyrene (PS) microsphere monolayer as the substrate. The immunoassay sensitivity of this biochip was found to be greatly improved compared with the conventional biochip built on glass slide. Further on-chip ELISA and optical calculation suggests that the improvement is not only associated with high capture efficiency of this biochip towards its target, but is also benefited from the porous PS monolayer enhanced intrinsic OIRD sensitivity via optical interference enhancement and effective dielectric constant effect. This work may provide valuable insight into the development of high performance label-free OIRD bio-detection devices.
研究领域:
生物技术
·
光学检测
·
免疫学
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Changxiang Fang,Changyin Zhong,Nan Chen,Lingya Yi,Junying Li,Weihua Hu
Quantitative detection of multiple biological small molecules is critical for health evaluation and disease diagnosis. In this study, a microarray chip featuring a bienzyme-immobilized polyaniline nanowire forest on fluorine-doped tin oxide (bienzyme-PANI/FTO) is developed for this purpose. On such a chip, the target molecules are oxidized under the catalysis of their attached oxidases to produce hydrogen peroxide, which further induces the partial oxidation of local PANI nanowires in the presence of horseradish peroxidase (HRP) enzyme. The redox state change of PANI nanowires is monitored by the oblique incident reflectivity difference (OIRD) technique in a real-time and wireless manner, thus allowing for quantitative analysis of the target molecules. As typical model targets, hydrogen peroxide, glucose, lactic acid, and cholesterol are successfully detected with low detection limits, excellent specificities, and broad detection ranges, all of which fully meet the requirements for clinical analysis of human serum samples. Simultaneous detection of multiple targets on an individual chip is further demonstrated using the OIRD scanning mode. Meanwhile, by simple electrochemical reduction of the PANI nanowires, the chip is reusable for more than eight detection cycles without evident decay in its performance. The detection principle of this chip is also universal to other small molecules, and thus, it shows great promise as a valuable device to analyze biological small molecules.
研究领域:
生物医学工程
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分析化学
·
临床诊断
✓ 已验证
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2024
·
IF 6.7
Xiaoyi Li,Shiming Wu,Zhihao Feng,Ke Ning,Dandan Ji,Ling Yu,Weihua Hu
Oblique-incidence reflectivity difference (OIRD) is a novel real-time, label-free, and nondestructive optical detection method and exhibits encouraging application in the detection of antibody/DNA microarrays. In this study, for the first time, an OIRD label-free immunoassay was achieved by using adherent live cells as the probe. The cells were cultured on glass cells, and the affinity binding of antibodies targeted on the HLA class I antigen of the cell surface was detected with an OIRD. The results show that an OIRD is able to detect the binding process of anti-human HLA-A, B, and C antibodies on MDA-MB-231 cells and HUVEC cells. Control experiments and complementary fluorescence analysis confirmed the high detection specificity and good quantitative virtue of the OIRD label-free immunoassay. Label-free OIRD imaging analysis of cell microarrays was further demonstrated successfully, and the underlying optical mechanism was revealed by combining the theoretical modeling. This work explores the use of live cells as probes for an OIRD immunoassay, thus expanding the potential applications of the OIRD in the field of pathological analysis, disease diagnosis, and drug screening, among others.
研究领域:
生物医学工程
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分子生物学
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光学检测
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2025
·
IF 6.7
Meng Li,Yuanyuan Xie,Dandan Ji,Ling Yu,Weihua Hu
Immunohistochemistry (IHC) is a well-established method in tissue pathology and finds critical applications in both clinical and fundamental medical science. Generally, labeled antibodies are a requisite for IHC to visualize the spatial distribution of the biomarker (antigen) of interest in the tissue slices. In this work, a label-free IHC imaging strategy is reported for the first time by using an oblique-incidence reflectivity difference (OIRD) to obviate the need for labeled antibodies. The position-resolved relative abundance of biomarkers was successfully mapped by the differential OIRD image upon the binding of native antibody on the tissue slices. The dynamic binding kinetics of antibody on the tissue are also monitored. The efficacy of such a label-free IHC strategy is further verified with fluorescent IHC images. This work explores the application of the OIRD imaging technique in tissue slices and offers a label-free IHC imaging strategy for pathological analysis, disease diagnosis, and drug screening.
研究领域:
病理学
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医学影像
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICS AND LASER TECHNOLOGY
·
2025
·
IF 5
Dailin Li,Jinlin Gui,Dingshan Chi,Mingze Li,Guangdi Wang,Shuo Yang,Yingying Gu
The intermolecular interactions between microemulsions and rock interfaces are key to regulating the properties of reservoir interfaces. Therefore, the focus of research on reservoir interface properties lies in the coupling mechanism between hydrogen bonding networks and interfacial electric potentials, which macroscopically manifests as the relationship between interfacial layer thickness and dielectric properties. In this study, the oblique-incidence reflectivity difference (OIRD) technique—highly sensitive to variations in interfacial thickness and permittivity—is employed for the optical characterization of reservoir rocks and the study of microemulsion phase transition behavior. The two-dimensional OIRD imaging experiment achieves the physical characterization of mineral and organic component distribution on oil shale surfaces. Diffusion kinetics experiments reveal that individual microemulsion components exhibit significantly different diffusion behaviors on the oil shale surface. These differences are influenced by factors such as fluid polarity, interfacial tension, mineral composition, and pore structure. Phase transition experiments demonstrate that microemulsions undergo phase transitions from water-in-oil (W/O) to bicontinuous and eventually to oil-in-water (O/W) with increasing water content. This work contributes to the study of reservoir interfacial properties and microemulsion enhanced oil recovery.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2022
·
IF 8.008
Changxiang Fang,Junying Li,Zhihao Feng,Xiaoyi Li,Min Cheng,Yan Qiao,Weihua Hu
Extracellular electron transfer (EET) is a critical process involved in microbial fuel cells. Spatially resolved mapping of EET flux is of essential significance due to the inevitable spatial inhomogeneity over the bacteria/electrode interface. In this work, EET flux of a typical bioanode constructed by inhabiting Shewanella putrefaciens CN32 on a porous polyaniline (PANI) film was successfully mapped using a newly established oblique incident reflectivity difference (OIRD) technique. In the open-circuit state, the PANI film was reduced by the electrons released from the bacteria via the EET process, and the resultant redox state change of PANI was sensitively imaged by OIRD in a real-time and noninvasive manner. Due to the strong correlation between the EET flux and OIRD signal, the OIRD differential image represents spatially resolved EET flux, and the in situ OIRD signal reveals the dynamic behavior during the EET process, thus providing important spatiotemporal information complementary to the bulky electrochemical data.
研究领域:
生物工程
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电化学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LAB ON A CHIP
·
2023
·Vol. 23
·期 10
·2477-2486
·
IF 6.1
Xiaoyi Li,Zhihao Feng,Changxiang Fang,Yunpeng Wei,Dandan Ji,Weihua Hu
Oblique-incidence reflectivity difference (OIRD) is a compelling technique for real-time, label-free and non-destructive detection of antibody microarray chips, but its sensitivity needs essential improvement for clinical diagnosis. In this study, we report an innovative high-performance OIRD microarray by using poly[oligo(ethylene glycol) methacrylate-co-glycidyl methacrylate] (POEGMA-co-GMA) brush grafted fluorine-doped tin oxide (FTO) as the chip substrate. The polymer brush enhances the interfacial binding reaction efficiency of targets from the complicated sample matrix due to its high antibody loading and excellent anti-fouling merits; the FTO-polymer brush layered structure, on the other hand, excites the interference enhancement effect of OIRD to achieve enhanced intrinsic optical sensitivity. Synergistically, the sensitivity of this chip is significantly improved compared to rival chips, achieving a limit of detection (LOD) as low as 25 ng mL−1 for the model target C-reactive protein (CRP) in 10% human serum. This work explores the tremendous influence of the chip interfacial structure on the OIRD sensitivity and proposes a rational interfacial engineering strategy to boost the performance of the label-free OIRD based microarray and other bio-devices.
研究领域:
材料科学
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生物医学工程
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分析化学
·
光学
✓ 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）