- 标题
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- 实验方案
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Co-ordinated Split Aptamer Assembly and Disassembly on Gold Nanoparticle for Functional Detection of HIV-1 Tat
摘要： Human immunodeficiency virus (HIV) is a life threatening, weakens the immune system upon infection, thus ultimately resulting in the fatal health issues. This situation necessitates the generation of different strategies for HIV detection. HIV-1 Tat, a transactivator of HIV gene expression, was chosen in this study as the target of a non-functional split aptamer. Implementation of split aptamer has been demonstrated in this work for colorimetric detection of HIV-1 Tat. An unmodified gold nanoparticle (GNP)-based colorimetric assay was used for the visible detection of the proof, displays color transitions from red to purple in relation to the dose-dependency of HIV-1 Tat against the split aptamer in ionic solutions. The visible color transition was characterized using UV-Vis spectrophotometer showing spectrum shift and supported by Scanning Electron Microscopy observation. With addition of sodium chloride, the color of the solution started to change to purple and spectrum started to shift to higher wavelength due to aggregation at HIV-1 Tat concentration as low as 10 nM. Specificity test was conducted with duplexed split aptamer and HIV-1 p24 has shown slight color changes. With HIV-1 Nef, GNP solution retains the color similar to the control, which indicated the specific split aptamer interaction to HIV-1 Tat.
关键词： Colorimetry,HIV-1 Tat,Gold nanoparticle,Split aptamer
更新于2025-09-23 15:19:57
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A paper-based colorimetric microfluidic sensor fabricated by a novel spray painting prototyping process for iron analysis
摘要： A novel, simple and low-cost spray painting technique has been developed for the fabrication of microfluidic paper-based devices. The devices that we developed utilize aerosol spray paint to build hydrophobic barriers and employ a hole puncher to obtain paper-based patterned layers and paper dots without using any specialized instruments (e.g., without a laser cutter). The entire manufacturing process is extremely simple, inexpensive and rapid, which can be applied broadly. Furthermore, the application of the device to iron detection was demonstrated. A linear relationship between the color value and the iron concentration was observed from 0 to 0.02 g/L. The developed microfluidic paper-based device for iron detection exhibited a low detection limit (0.00090 g/L), good selectivity and acceptable recovery.
关键词： Spray painting,Colorimetry,Microfluidic paper-based device,Iron
更新于2025-09-19 17:15:36
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Cell Phone based Colorimetric Analysis for Point-of-Care Settings
摘要： Cell phones show considerable promise for point-of-care (POC) diagnostic procedures because they are accessible, connected, and computationally powerful. Cell phone image processing methods are being developed for the detection and quantification of a wide range of targets, employing methods from microscopy to fluorescence techniques. However, most of the lab-based biological and biochemical assays still lack a robust and repeatable cell phone analogue. Existing solutions require external smartphone hardware to obtain quantitative results, imposing a design tradeoff between accessibility and accuracy. Here, we develop a cell phone imaging algorithm that enables analysis of assays that would typically be evaluated via spectroscopy. The developed technique uses the saturation parameter of hue-saturation-value color space to enable POC diagnosis. Through the analysis of over 10,000 images, we show that the saturation method consistently outperforms existing algorithms under a wide range of operating field conditions. The performance improvement is also proven analytically via the mathematic relationship between the saturation method and existing techniques. The method presented here is a step forward towards the development of POC diagnostics by reducing the required equipment, improving the limit of detection (LOD), and increasing the precision of quantitative results.
关键词： Spectroscopy,Cell Phone Imaging,Point-of-Care Diagnostics,Colorimetry
更新于2025-09-19 17:15:36
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The Impact of Laser Radiation on Polypropylene Molded Pieces Depending on Their Surface Conditions
摘要： The article presents an analysis of the impact of a laser beam interaction (Nd: YVO4) with selected operational parameters on the quality of graphical marks obtained on the surfaces of polypropylene-molded pieces with di?erent surface textures (variable parameters of the surface layer). Polypropylene test specimens were produced by injection using the original injection mold, which allowed for the obtainment of products with variable surface ?nish parameters determined by the surface condition of the forming cavity. The presented relationship between the parameters of laser performance, the texture of a molded piece surface, the molded piece’s color, and types of masterbatches supporting the marking process allows for the assessment of the e?ciency of graphic symbol application by laser marking. The original evaluation criteria for the conducted process were adopted.
关键词： laser marking,polypropylene,laser marking masterbatch,colorimetry,surface ?nishing
更新于2025-09-19 17:13:59
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Spectral Image Processing for Museum Lighting Using CIE LED Illuminants
摘要： This work presents a spectral color-imaging procedure for the detailed colorimetric study of real artworks under arbitrary illuminants. The results demonstrate this approach to be a powerful tool for art and heritage professionals when deciding which illumination to use in museums, or which conservation or restoration techniques best maintain the color appearance of the original piece under any illuminant. Spectral imaging technology overcomes the limitations of common area-based point-measurement devices such as spectrophotometers, allowing a local study either pixelwise or by selected areas. To our knowledge, this is the ?rst study available that uses the proposed CIE (Commission Internationale de l’éclairage) light-emitting diode (LED) illuminants in the context of art and heritage science, comparing them with the three main CIE illuminants A, D50, and D65. For this, the corresponding colors under D65 have been calculated using a chromatic adaptation transform analogous to the one in CIECAM02. For the sample studied, the CIE LED illuminants with the lowest average CIEDE2000 color di?erences from the standard CIE illuminants are LED-V1 for A and LED-V2 for D50 and D65, with 1.23, 1.07, and 1.57 units, respectively. The work studied is a Moorish epigraphic frieze of plasterwork with a tiled skirting from the Nasrid period (12th–15th centuries) exhibited in the Museum of the Alhambra (Granada, Spain).
关键词： CIEDE2000,hyperspectral line scanner,CIE illuminants,colorimetry,spectral imaging
更新于2025-09-12 10:27:22
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Fluorescence hyperspectral image technique coupled with HSI method to predict solanine content of potatoes
摘要： In order to ensure the edibility of potatoes, fluorescence hyperspectral images of potato samples were obtained to predict the solanine content in potatoes. For the best ROI (region of interest), the S‐component of saturation was extracted by the HSI colorimetric technology to characterize the bud eye of potatoes in three‐dimensional geometric space. The effective bud eye was located as the geometric center of ROI and the average spectral information was obtained. After pretreatment and selection of feature wavelengths, the predicting mode of SVR was established and was optimized by adjusting the penalty coefficient c and the core coefficient g of radial basis function (RBF). Finally, the determinant coefficient of the model was 0.9143 and the root mean square error was 0.0296, which could basically meet the application requirements. It was concluded that the method based on hyperspectral fluorescence image and HSI colorimetry could predict the solanine content in potatoes accurately through the optimized SVR model.
关键词： SVR model,fluorescence hyperspectral image,potatoes,HSI colorimetry,solanine content
更新于2025-09-11 14:15:04
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[IEEE 2019 Second Balkan Junior Conference on Lighting (Balkan Light Junior) - Plovdiv, Bulgaria (2019.9.19-2019.9.21)] 2019 Second Balkan Junior Conference on Lighting (Balkan Light Junior) - The LED spectral power distribution modelled by different functions - how spectral matching quality affected computed LED color parameters
摘要： The paper is describing different alternatives for mathematical modelling of LED’s spectral power distribution. logistic power peak and asymmetric double Gaussians, sigmoidal functions are tested with different shape and peak wavelength LEDs. Article shows how SPD accuracy modeling is affecting color quality parameters and luminous efficiency of LED. Consequences of applying always single SPD model for different LED emitters are shown for chosen parameters.
关键词： colorimetry,spectral power distribution,light emitting diode,mathematical modeling
更新于2025-09-11 14:15:04
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P‐15.3: The Importance of Centroid Wavelength for the Image Quality Evaluation of Laser Displays
摘要： The accuracy of a measurement method for the chromaticity and photometric quantity of laser displays using centroid wavelengths was experimentally verified. This method allows more accurate optical evaluation of laser displays in principle than the method using peak wavelengths which has been commonly known in the laser industry.
关键词： Chromaticity,Tristimulus Values,Peak Wavelength,Colorimetry,Laser,Laser Display,Radiometric Quantity,Centroid Wavelength,Photometric Quantity,Photometry
更新于2025-09-11 14:15:04
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P‐15.2: A Study for Easy and Quick White Balance Adjustment in Laser Display Production
摘要： White balance adjustment is crucially important but time-consuming work in display production. In this paper, we point out challenges in white balance adjustment process and discuss how they can be resolved using the Discrete Centroid Wavelength Method, which was newly developed for laser-display measurement.
关键词： Chromaticity,Tristimulus Values,Colorimetry,Laser,Optical Power,Laser Display,White Balance Adjustment,Centroid Wavelength,Photometric Quantity,Photometry,Power Meter
更新于2025-09-11 14:15:04
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Synthesis of green cool pigments (CoxZn1-xO) for application in NIR radiation reflectance
摘要： Reconciling green synthesis, sustainability and production of pigments for protection of solar radiation is a continuous topic of search for unique, versatile and environmental compatible methods. In this perspective, we present the green synthesis of inorganic pigments with reflective properties of infrared radiation in the NIR region. Green powder pigments described by CoxZn1-xO, were obtained via the gelatinization method of starch colloidal suspension with inorganic salts (zinc and cobalt), calcined at different temperatures. Structural, morphological and spectroscopic characterization showed the pigments present Wurtzite crystalline phase with compact hexagonal structure, and monophasic when obtained at a calcination temperature above 800 °C. Colorimetric measurements obtained by the CIE-L*a*b* method presented values related to green pigments attributed to cobalt ions, which replace the zinc ions in the Wurtzite matrix and corroborate the composition estimated by X-ray fluorescence analysis for Co0.1Zn0.9O. The pigments' NIR reflectivity increased with the calcination temperature increasing, with R% > 35%; and when the pigment is dispersed in a white paint the increase is R% > 50%. Therefore, our green pigments present great potential to be used as an active material in cold coatings and in solar devices.
关键词： Colorimetry,NIR reflectance,Cool pigments,Green synthesis
更新于2025-09-10 09:29:36