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The housing is inserted into the color analysis system and heated at 45 °C for 5 min to produce a purple-colored reaction complex. The complex is imaged using a CCD camera and the RGB color intensity of the image is then analyzed using a smartphone to determine the total protein (TP) concentration of the sample. The effectiveness of the proposed method is demonstrated using TP control samples with known concentrations in the range of 0.03-5.0 g/dL. The detection results obtained for 50 human urine samples obtained from random volunteers are shown to be consistent with those obtained from a conventional hospital analysis system (R2 = 0.992). Moreover, the detection results obtained for the albumin (ALB) and creatine (CRE) concentrations of 50 whole blood samples are also shown to be in good agreement with the results obtained from the hospital analysis system (R2 = 0.982 and 0.988, respectively).The continuous advancement of analytical technology has provided methods with increasing sensitivity and precision to detect genetically modified organisms (GMOs). Novel analytical strategy-based detection methods are alternatives to conventional polymerase chain reaction (PCR)-mediated assays, which are still the gold standard in this field. However, PCR primers and probes cannot be reused, which makes the technique uneconomical. Surface plasmon resonance (SPR) is an optical and label-free technique for studying ligand-analyte interactions, especially for DNA hybridization, and several SPR biosensors have been described for the detection of nucleic acids. Here, a multiplexed, regenerable and real-time SPR biosensor for the detection of GMOs is described. A biosensor was constructed for qualitative detection of T-nos, CaMV35S and cry1A and had good specificity and sensitivity. The limit of detection (LOD) of this biosensor was 0.1 nM without any signal amplification. Furthermore, our biosensor could be stably regenerated more than 100 times over at least 20 days and showed good reproducibility. This nucleic acid SPR biosensor has potential for application in other types of biological detection.Amyloid-β oligomer is an important biomarker and a potential therapeutic target of Alzheimer's disease in its early stage. Here, we combined superhydrophobic carbon fiber paper (CFP) with AuPt alloy nanoparticles to prepare a CFP/AuPt nanocomposite with larger specific surface area and hydrophobic surface. On this basis, we constructed an electrochemical aptasensor based on CFP/AuPt for the ultrasensitive detection of amyloid-β oligomers. The surface-coated AuPt nanoparticles greatly enhanced the electroactive area, and the hydrophobic surface increased the resisting nonspecific adsorption performance of sensor. A combination of these two features significantly improved the sensitivity and specificity of the sensor. This electrochemical aptasensor based on CFP/AuPt displayed a low detection limit of 0.16 pg/mL. This work shows a promising future in clinical diagnosis of Alzheimer's disease and provides a possible solution to electrochemical biosensors that are susceptible to interference in biological fluids.Phthalates (PAEs) are known as endocrine disruptors that can have adverse effects on human hormonal balance and development. Due to PAEs being semi-volatile chemical compounds, they can sustainably emit from the surfaces of objects containing PAEs. Face masks are commonly used to safeguard human health especially during periods of high prevalence of infectious diseases. As masks come into direct contact with the human respiratory system, PAEs from masks will enter the human body directly from the respiratory system thus potentially threatening human health. In this study, the desorption corona beam ionization (DCBI)-MS/MS method for the rapid in-situ detection of PAEs in face masks was established, which could perform ultra-fast, high-throughput identification and quantitative analysis on 13 kinds of PAEs, and the limits of detection (LODs) were 0.7 μg m-2 for DAP, BBP, DBP, DPP, DHXP, DEHP, DINP and DDP, 1.4 μg m-2 for DMEP, DEP, DPhP, DBEP and DNOP. Compared with the traditional liquid chromatography tandem mass spectrometry, this study shows that the DCBI-MS/MS method has the following advantages 1) short analysis time, less than 1 min; 2) small solvent consumption, less than 10 μL; 3) the PAEs in face masks can be quickly in-situ screened.Heavy metals detection is of great significance to the environment and human health, and most of the detection methods require expensive instruments and laborious operation. Herein, we present a coordination array for accurate and rapid colorimetric heavy metal ions sensing. The array was composed of six chelates and has cross response to Hg2+, Cd2+, Pb2+ and Cu2+. The results could be observed by naked eyes or detected by plate reader combined with pattern analysis. Linear discrimination analysis was applied for the pattern analysis and the four heavy metal ions (Pb2+, Cd2+, Hg2+ and Cu2+) generated a clustering map at 1 μM. The coordination array demonstrates a great potential for sensing heavy metal ions simultaneously.Surface sampling for trace explosives residues is a critical step in the security screening in which microparticles are collected for subsequent chemical analysis. The current surface swabbing approach suffers from limited sampling area coverage, uncertainty in harvesting efficiencies, and user bias. Non-contact sampling has received interest due to its ability to interrogate large surface areas without the redeposition of the collected sample. read more However, the aerodynamic liberation of energetic particles from different types of substrates has not been parameterized or directly compared with the contact sampling methods. Here, we report aerodynamic resuspension rates of TNT, RDX, and HMX microparticles from smooth, rough, and fibrous surfaces. The resuspension thresholds are correlated to the boundary layer properties, i.e., wall shear stresses (τw = 50-500Pa). These rates are then compared to contact sampling for five commercial swabs using a standardized swabbing method. LC-MS analysis is used for the quantification of particle removal efficiencies.