Zhoubekker5642
1% (w/w) of polymorphic impurity detection) for medium (150 x 150 pixels) and big (1000 x 1000 pixels) map sizes in less than 2 min. Moreover, in the case of falsified medicines, it is demonstrated that the proposed approach allows the identification of all compounds, found in very different proportions and, sometimes, in trace amounts. Furthermore, the relevant spectral signatures for which no match is found in the reference database can be identified at a later stage and the nature of the corresponding compounds further investigated. Overall, the provided results show that Raman hyperspectral imaging combined with PBI enables rapid and reliable spectral identification of complex pharmaceutical formulations.Nowadays, contamination of various mycotoxins in crops and their products exposes increasing risks to human health. Efficient determination methods are urgently needed. Herein, a bifunctional aptamer and a simple aptasensor based on microscale thermophoresis assay (MST) were constructed for the first time for simultaneous determination of two mycotoxins, i.e. zearalenone (ZEN) and ochratoxin A (OTA). The bifunctional aptamer was engineered by splicing a ZEN aptamer and an OTA aptamer with a linker according to the structure analysis of aptamers. The binding mechanism of the bifunctional aptamer to ZEN and OTA were revealed basing on the molecular docking studies. The MST assay proved that the bifunctional aptamer showed high affinity and specificity towards ZEN and OTA. Furthermore, a bifunctional aptamer-based MST-aptasensor was developed for simultaneous detection of ZEN and OTA in corn oil sample. The MST-aptasensor provided a limit of detection (LOD) of 0.12 nM, with satisfactory recoveries of 93.31-104.19% and excellent selectivity, indicating that the bifunctional aptamer and MST-aptasensor had great potential in practical applications.Dysregulation of phosphorylation-mediated signaling drives the initiation and progression of many diseases. A substrate-specific kinase assay capable of quantifying the altered site-specific phosphorylation of its phenotype-dependent substrates provides better specificity to monitor a disease state. We report a sensitive and rapid substrate-specific kinase assay by integrating site-specific peptide reporter and multiple reaction monitoring (MRM)-MS platform for relative and absolute quantification of substrate-specific kinase activity at the sensitivity of nanomolar kinase and nanogram cell lysate. Using non-small cell lung cancer as a proof-of-concept, three substrate peptides selected from constitutive phosphorylation in tumors (HDGF-S165, RALY-S135, and NRD1-S94) were designed to demonstrate the feasibility. this website The assay showed good accuracy ( less then 15% nominal deviation) and reproducibility ( less then 15% CV). In PC9 cells, the measured activity for HDGF-S165 was 3.2 ± 0.2 fmol μg-1 min-1, while RALY-S135 and NRD1-S94 showed 4- and 20-fold higher activity at the sensitivity of 25 ng and 5 ng lysate, respectively, suggesting different endogenous kinases for each substrate peptide. Without the conventional shotgun phosphoproteomics workflow, the overall pipeline from cell lysate to MS data acquisition only takes 3 h. The multiplexed analysis revealed differences in the phenotype-dependent substrate phosphorylation profiles across six NSCLC cell lines and suggested a potential association of HDGF-S165 and NRD1-S94 with TKI resistance. With the ease of design, sensitivity, accuracy, and reproducibility, this approach may offer rapid and sensitive assays for targeted quantification of the multiplexed substrate-specific kinase activity of small amounts of sample.Spatially resolved metabolomics offers unprecedented opportunities for elucidating metabolic mechanisms during cancer progression. It facilitated the discovery of aberrant cellular metabolism with clinical application potential. Here, we developed a novel strategy to discover cancer tissue relevant metabolic signatures by high spatially resolved metabolomics combined with a multicellular tumor spheroid (MCTS) in vitro model. Esophageal cancer MCTS were generated using KYSE-30 human esophageal cancer cells to fully mimic the 3D microenvironment under physiological conditions. Then, the spatial features and temporal variation of metabolites and metabolic pathways in MCTS were accurately mapped by using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) with a spatial resolution at ∼12 μm. Metabolites, such as glutamate, tyrosine, inosine and various types of lipids displayed heterogeneous distributions in different microregions inside the MCTS, revealing the metabolic heterogenicity of cancer cells under different proliferative states. Subsequently, through joint analysis of metabolomic data of clinical cancer tissue samples, cancer tissue relevant metabolic signatures in esophageal cancer MCTS were identified, including glutamine metabolism, fatty acid metabolism, de novo synthesis phosphatidylcholine (PC) and phosphatidylethanolamine (PE), etc. In addition, the abnormal expression of the involved metabolic enzymes, i.e., GLS, FASN, CHKA and cPLA2, was further confirmed and showed similar tendencies in esophageal cancer MCTS and cancer tissues. The MALDI-MSI combined with MCTS approach offers molecular insights into cancer metabolism with real-word relevance, which would potentially benefit the biomarker discovery and metabolic mechanism studies.Due to high mixing performance and simple geometry structure, serpentine micromixer is one typical passive micromixer that has been widely investigated. Traditional zigzag and square-wave serpentine micromixers can achieve sufficient mixing, but tend to induce significant pressure drop. The excessive pressure drop means more energy consumption, which leads to low cost-performance of mixing. To mitigate excessive pressure drop, a novel serpentine micromixer utilizing ellipse curve is proposed. While fluids flowing through ellipse curve microchannels, the flow directions keep continuous changing. Therefore, the Dean vortices are induced throughout the whole flow path. Numerical simulation and visualization experiments are conducted at Reynolds number (Re) ranging from 0.1 to 100. Dean vortices varies with the changing curvature in different ellipse curves, and local Dean numbers are calculated for quantitative evaluation. The results suggest that the ellipse with a larger eccentricity induces stronger Dean vortices, thus better mixing performance can be obtained.