Sensing and Bio-Sensing Research最新文献

The design and analysis of gas detection chips directly affect their detection efficiency and applicability. Detection devices are currently restricted by detection principles, facing drawbacks like intricate structural design, limited applicability, and low detection efficiency. We have designed a complete set of design and analysis scheme for a peptide gas detection chip. First, we selected specific and high-affinity peptide combinations from existing peptide-gas affinity datasets. Then, the peptide chip's arrangement was grouped according to the variations in peptides' affinity towards different gases. Peptides were arranged based on their affinity levels within each group, striking a balance between discrimination and flexibility in the design of the chip. Finally, we evaluated the analysis methods by generating simulated data based on a reference affinity matrix constructed from actual data. Due to the preprocessing role of chip design on affinity data, all methods can effectively accomplish gas classification. In gas concentration prediction tasks, our method reduced mean square error to 0.41, significantly outperforming other methods. This gas detection scheme shortens the development cycle of chip design and analysis methods, fully utilizing the specificity of peptides, enhancing gas analysis effectiveness, and demonstrating the agile development of gas detection chips.

In this study, Sediment Microbial Fuel Cells (SMFCs) prototypes have been developed to operate under open-air conditions and power sensors for environmental monitoring. Two SMFCs with a volume of 50 l each, consisting of two types of anodic materials – graphite and coke, were operated on-field for over a year. The electrical outputs have been recorded and compared with the measured environmental parameters such as temperature, light illumination, atmospheric pressure, humidity, etc. The statistical analysis of the obtained data shows that temperature changes between 0 and 14 °C do not affect the power achieved. On the contrary, the sunlight irradiation showed a second-order polynomial correlation with the current generated by the SMFCs, increasing the latter during the days. The cathode reactions significantly impacted the power density achieved by both explored SMFCs and the system's sustainability. The metallurgical coke is suggested to be used as an inexpensive and convenient anode material for SMFCs giving compatible results to the widely used graphite.

Due to the global pandemic of influenza and related respiratory diseases, rapid and accurate detection is in high demand to control virus spread and facilitate early treatment. However, most current molecular detection methods either require long turnaround times, suffer from low sensitivity and/or can only detect single pathogens. To overcome these challenges, we constructed a novel colorimetric gold nanoparticle (AuNPs) biosensor containing functionalized probes to detect multiple targets simultaneously. Utilizing the salt aging method, AuNPs were functionalized by the designed oligonucleotides to fabricate biosensors. This biosensor can show visible color change within 20 min, and could minimally detect the target influenza viruses at 10 nM. This detection technique presents high sensitivity in a short time, meanwhile identifying two different influenza viruses simultaneously. It opens a window to a multiplex-in-one strategy for a clinical viral diagnostic.

Chemical submission, a nefarious tactic increasingly employed in criminal activities, has spurred urgent calls for innovative countermeasures. GHB, often dubbed “liquid ecstasy,” stands out as a favoured agent for its surreptitious nature and seamless solubility in water and alcoholic beverages. Addressing this menace head-on, a groundbreaking study delves into the development of advanced chemosensors, leveraging 2-aminonaphtoxazole- and benzoxazole-based compounds adorned with fluorescein, to construct a cellulose paper-based detection system. This ingenious setup not only detects GHB in water but extends its vigilance to real alcoholic and non-alcoholic beverages, illuminating a pathway to thwart potential assailants. With a fluorescence enhancement mechanism at play, the system boasts a dynamic range from 0 to 125 mM GHB in water, exhibiting a commendable limit of detection (LOD) at 7.3 mM. Crucially, its eco-friendly nature, devoid of solvent residuals, underscores its suitability as a proactive shield against chemical submission, embodying a beacon of hope in the fight against such insidious threats to public safety.

Biopsy-based histopathology and immunohistochemistry for cervical cancer detection are costly, time-consuming, and require expert personnel for data interpretation. We developed a simple magnetic nanoparticle (MNPs) and quantum dots (QD) coupled immuno nano fluorescence assay (MNPQDCINFA) for visual detection of HPV16-induced cervical cancer cells under UV light from cytology/biopsy samples exploiting host cancer cells expressing viral E7 protein as a biomarker. The E7 domain-specific polyclonal antibodies were generated against the 1–44 amino acid N-terminal (anti-domainN antibody) and 48–98 amino acid C-terminal domain (anti-domainC antibody). These antibodies were bioconjugated with nonfluorescent MNPs (60 % efficiency) and fluorescent QDs (66 % efficiency) to generate capturing (MNPs-anti-domainN antibody) and detecting (QDs-anti-domainC antibody) nano-complex, respectively. Assay conditions, such as concentration of capturing (20 μM) and detecting (50 nM) antibody nano-complexes and incubation duration (30 min), were standardized. The analytical sensitivity using pure HPV16 E7 protein was recorded up to 200 ng with very high specificity to differentiate from other HPV strains E7 proteins. The diagnostic performance characteristics with cytology samples showed 100 % sensitivity and specificity compared to immunofluorescence and biopsy-based histopathology analysis. The present invention can be effectively used for a quick, disposable, rapid cervical cancer cell detection system as an alternate test for immunofluorescence and histopathology.

A deep gold-coated sinusoidal grating is proposed as a transducer for label-free real-time biosensing, operating in a new configuration based on the optical switch effect, which produces complementary optical outputs enabling differential and referenced detection. Biosensing experiments are reported for the first time on this platform, using immunoassays involving biospecific pairs consisting of bovine serum albumin and its antibody, and human serum albumin and its antibody. Direct and sandwich immunoassays are demonstrated along with negative controls. A limit of detection of 6 pg/mm² was obtained. A theoretical model correlating the variation in the differential referenced output optical signal with adlayer growth is presented and supports the experimental results. The proposed detection device operating in the optical switch configuration makes a promising case for point-of-care detection applications because the differential detection of two diffracted orders enables common noise suppression and robust interrogation.

A proposal has been made to identify tuberculosis cells using a novel compact sensor based on photonic crystal fiber: PCF in accordance with hexagonal spectroscopy. This proposed structure, which consists of a closely packed hexagonal air hole in the cladding region and a hollow-core area, possesses a very low loss of 6.30 × 10⁻⁸ dB/m and an exceptionally high sensitivity of up to 91.75 % (tuberculosis cell for 1.345). Numerous optical parameters have been identified and assessed, comprised of the numerical aperture, the V-parameter, or normalized frequency (V_eff), and the effective area (A_eff). The operational wavelength range is defined as 0.80–3.0 THz. The numerical investigation of the properties of the proposed TB sensors is performed within the environment of COMSOL Multiphysics (Version 5.3) using FV-FEM stands for the full vector finite element method. PCF sensors composed of hexagonal lattice in a circular form with ZEONEX as the backdrop material is intended to boost the sensitivity response in comparison to the earlier works. Additionally, the sensor that is being displayed achieves a single modality throughout its whole operational wavelength range. This proposed sensor may play a significant role in identifying tuberculosis thanks to its superior sensitivity response and extremely minimal confinement loss. So, it is clearly seen that this sensor could be used to bio-medical sectors with process of terahertz (THz) wave pulse.