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- 摘要
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- 实验方案
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A portable and universal upconversion nanoparticle-based lateral flow assay platform for point-of-care testing
摘要： Upconversion nanoparticle-based lateral flow assays (UCNP-LFAs) have attracted significant attention in point-of-care testing (POCT) applications, due to the long-term photostability and enhanced signal-to-background noise ratio. The existing UCNP-LFAs generally require peripheral equipment for exciting fluorescent signals and reading out fluorescence results, which are generally bulky and expensive. Herein, we developed a miniaturized and portable UCNP-LFA platform, which is composed of a LFA detection system, an UCNP-LFA reader and a smartphone-assisted UCNP-LFA analyzer. The LFA detection system is based on three types of UCNPs for multiplexed detection. The reader has a dimension of 24.0 cm×9.4 cm×5.4 cm (L×W×H) and weight of 0.9 kg. The analyzer based on the custom-designed software of a smartphone (termed as UCNP-LFA analyzer) can get the quantitative analysis results in a real-time manner. We demonstrated the universality of this platform by highly sensitive and quantitative detections of several kinds of targets, including small molecule (ochratoxin A, OTA), heavy metal ion (Hg2+), bacteria (salmonella, SE), nucleic acid (hepatitis B virus, HBV) and protein (growth stimulation expressed gene 2, ST-2). Our developed UCNP-LFA platform holds great promise for applications in disease diagnostics, environmental pollution monitoring and food safety at the point of care.
关键词： UCNP-based biosensor,telemedicine,point-of-care diagnostics,paper microfluidics,multiplexed detection,miniaturized device
更新于2025-11-28 14:23:57
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Investigation of Keratinizing Squamous Cell Carcinoma of the Tongue Using Terahertz Reflection Imaging
摘要： We investigated the feasibility of using terahertz (THz) reflection imaging to detect keratinizing squamous cell carcinoma (SCC) of the tongue. Four fresh keratinizing SCC tissues were studied, which had been surgically resected. All of the keratinizing SCCs were well distinguished from normal healthy tissues. We showed that the tumor regions exhibited low THz reflection despite having higher water content than normal regions. The refractive indices and absorption coefficients were low in the tumor tissues despite the relatively high water content. Our results showed that there were dominant factors such as keratin pearls, other than the water content affecting the THz reflection signal.
关键词： Optical diagnostics for medicine,Tissue diagnostics,Terahertz imaging,Medical and biological imaging,Terahertz spectroscopy
更新于2025-09-23 15:23:52
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A Study of Two Dimensional Tomography Reconstruction of Temperature and Gas Concentration in a Combustion Field Using TDLAS
摘要： Based on tunable diode laser absorption spectroscopy (TDLAS), two-dimensional (2D) distribution reconstructions of gas concentration and temperature are realized using an algebraic reconstruction technique (ART). The influence of the beam distribution and grid size on combustion field reconstruction is investigated to attain optimal reconstruction results with a limited number of beams. Under limited optical-path numbers, it shows that a better spatial resolution is attainable only when the laser beam paths are vertical and parallel to the symmetry axis of the combustion field. Furthermore, experiments with 16 beam paths using one and two flat flame combustion fields are carried out in different fuel-air equivalence ratios under room temperature. The results are in agreement with the simulation results, and the time resolution is less than 1 s.
关键词： tomographic imaging,diode lasers,temperature,spectroscopy,combustion diagnostics,absorption
更新于2025-09-23 15:23:52
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Graphene oxide-quenching-based fluorescence in situ hybridization (G-FISH) to detect RNA in tissue: Simple and fast tissue RNA diagnostics
摘要： FISH-based RNA detection in paraffin-embedded tissue can be challenging, with complicated procedures producing uncertain results and poor image quality. Here, we developed a robust RNA detection method based on graphene oxide (GO) quenching and recovery of fluorescence in situ hybridization (G-FISH) in formalin-fixed paraffin-embedded (FFPE) tissues. Using a fluorophore-labeled peptide nucleic acid (PNA) attached to GO, the endogenous long noncoding RNA BC1, the constitutive protein β-actin mRNA, and miR-124a and miR-21 could be detected in the cytoplasm of a normal mouse brain, primary cultured hippocampal neurons, an Alzheimer’s disease model mouse brain, and glioblastoma multiforme tumor tissues, respectively. Coding and non-coding RNAs, either long or short, could be detected in deparaffinized FFPE or frozen tissues, as well as in clear lipid-exchanged anatomically rigid imaging/immunostaining-compatible tissue hydrogel (CLARITY)-transparent brain tissues. The fluorescence recovered by G-FISH correlated highly with the amount of miR-21, as measured by quantitative real time RT-PCR. We propose G-FISH as a simple, fast, inexpensive, and sensitive method for RNA detection, with a very low background, which could be applied to a variety of research or diagnostic purposes.
关键词： glioblastoma multiforme tumor,tissue RNA diagnostics,Graphene oxide-quenching-based fluorescence in situ hybridization (G-FISH),Alzheimer’s disease,formalin-fixed paraffin-embedded (FFPE) tissue
更新于2025-09-23 15:23:52
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3D Mueller-Matrix Diffusive Tomography of Polycrystalline Blood Films for Cancer Diagnosis
摘要： The decomposition of the Mueller matrix of blood films has been carried out using differential matrices with polarized and depolarized parts. The use of a coherent reference wave is applied and the algorithm of digital holographic reconstruction of the field of complex amplitudes is used. On this basis, the 3D Mueller-matrix diffuse tomography method—the reconstruction of distributions of fluctuations of linear and circular birefringence of depolarizing polycrystalline films of human blood is analytically justified and experimentally tested. The dynamics of the change in the magnitude of the statistical moments of the first-fourth order, which characterize layer-by-layer distributions of fluctuations in the phase anisotropy of the blood film, is examined and analyzed. The most sensitive parameters for prostate cancer are the statistical moments of the third and fourth orders, which characterize the asymmetry and kurtosis of fluctuations in the linear and circular birefringence of blood films. The excellent accuracy of differentiation obtained polycrystalline films of blood from healthy donors and patients with cancer patients was achieved.
关键词： polarimetry,Mueller-matrix,blood,cancer diagnostics,polarization
更新于2025-09-23 15:23:52
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AIP Conference Proceedings [Author(s) 4TH ELECTRONIC AND GREEN MATERIALS INTERNATIONAL CONFERENCE 2018 (EGM 2018) - Bandung, Indonesia (27–28 July 2018)] - Multichannel PDMS microfluidic based nano-biolab-on-a-chip for medical diagnostics
摘要： Multichannel PDMS microfluidic based nano-biolab-on-a-chip for medical diagnostics
关键词： medical diagnostics,PDMS,microfluidic,nano-biolab-on-a-chip
更新于2025-09-23 15:23:52
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Using a commercial mini-X-ray source for calibrating Bragg crystals
摘要： In this paper we describe a procedure for calibration of Bragg crystals used for X-ray spectroscopy of laser plasmas. The method uses a relatively inexpensive commercially available X-ray source. By using the source to pump a metallic foil such as vanadium or titanium we were able to create a K-α emission source with minimal background radiation outside the desired photon energy. By using photon counting techniques with a CCD detector we were able to get absolute calibrations of curved and flat Bragg crystals in the 4–5 keV region. An important advantage of our method is that absolute calibration was not necessary either for the commercial source or the detector.
关键词： X-ray detectors and telescopes,spectroscopy and imaging,Plasma diagnostics - interferometry
更新于2025-09-23 15:23:52
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A fluorometric method for determination of the activity of T4 polynucleotide kinase by using a DNA-templated silver nanocluster probe
摘要： The authors describe a turn-off fluorometric method for the determination of the activity of the T4 polynucleotide kinase (T4 PNK). It is based on the use of DNA-templated silver nanoclusters (AgNCs). DNA probes with terminal 5′ hydroxy groups are used as substrates for DNA phosphatases. If subsequently treated with T4 PNK and Lambda exonuclease (λ exo), the AgNC DNA probes with a modified C-rich sequence and the G-rich sequence is separated. Upon their separation, the strong fluorescence (with excitation/emission maxima at 580/650 nm) that is caused by the proximity of the G-rich region and the C-rich region in the AgNCs decreases sharply. This enabled the fluorometric kinetic determination of the activity of T4 PNK. The assay is characterized by a wide linear range (from 0.01 to 12.5 U·mL?1), a low detection limit (0.01 U·mL?1) and short assay time (typically 60 min). This makes it a promising tool for use in studying processes related to DNA phosphorylation, in drug discovery and in diagnostics.
关键词： DNA-AgNCs,Cell extracts,Clinical diagnostics,Lambda exonuclease,Proximity effect,T4 PNK,Inhibitor,ATP,Na2HPO4,Phosphorylation
更新于2025-09-23 15:23:52
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Enlargement of Gold Nanoparticles for Sensitive Immunochromatographic Diagnostics of Potato Brown Rot
摘要： Lateral ?ow immunoassay (LFIA) is a convenient tool for rapid ?eld-based control of various bacterial targets. However, for many applications, the detection limits obtained by LFIA are not suf?cient. In this paper, we propose enlarging gold nanoparticles’ (GNPs) size to develop a sensitive lateral ?ow immunoassay to detect Ralstonia solanacearum. This bacterium is a quarantine organism that causes potato brown rot. We fabricated lateral ?ow test strips using gold nanoparticles (17.4 ± 1.0 nm) as a label and their conjugates with antibodies speci?c to R. solanacearum. We proposed a signal enhancement in the test strips’ test zone due to the tetrachloroauric (III) anion reduction on the GNP surface, and the increase in size of the gold nanoparticles on the test strips was approximately up to 100 nm, as con?rmed by scanning electron microscopy. Overall, the gold enhancement approach decreased the detection limit of R. solanacearum by 33 times, to as low as 3 × 104 cells·mL–1 in the potato tuber extract. The achieved detection limit allows the diagnosis of latent infection in potato tubers. The developed approach based on gold enhancement does not complicate analyses and requires only 3 min. The developed assay together with the sample preparation and gold enlargement requires 15 min. Thus, the developed approach is promising for the development of lateral ?ow test strips and their subsequent introduction into diagnostic practice.
关键词： gold nanoparticles,immunochromatographic diagnostics,potato brown rot,gold particle growth,increase of sensitivity,lateral ?ow immunoassay,test strips,Ralstonia solanacearum
更新于2025-09-23 15:22:29
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Analysis of Optical Plasma Monitoring in Plasma-Enhanced Atomic Layer Deposition Process of Al <sub/>2</sub> O <sub/>3</sub>
摘要： A noninvasive, optical plasma monitoring method in plasma-enhanced atomic layer deposition (PEALD) process for nanoscale water vapor barrier film is presented. Any equipment malfunction, as well as a deviation in the condition of individual components can easily jeopardize the process result. Al2O3 deposition process was employed in this research as a test vehicle, and high-speed optical plasma monitoring was demonstrated. It is shown that optical plasma monitoring is useful for not only measuring plasma pulses in real time, but also for the detection of any variation in plasma condition which enables inferring plasma dynamics for advanced process control in nanoscale thin film deposition process.
关键词： PEALD,Process Monitoring,Plasma Diagnostics,Fault Detection
更新于2025-09-23 15:22:29