Rapid advances in front-end separation approaches and analytical technologies have accelerated the development of lipidomics, particularly in terms of increasing analytical coverage to encompass an expanding repertoire of lipids within a single analytical approach. Developments in lipid pathway analysis, however, have somewhat lingered behind, primarily due to (1) the lack of coherent alignment between lipid identifiers in common databases versus that generated from experiments, owing to the differing structural resolution of lipids at molecular level that is specific to the analytical approaches adopted by various laboratories; (2) the immense complexity of lipid metabolic relationships that may entail head group changes, fatty acyls modifications of various forms (e.g. elongation, desaturation, oxidation), as well as active remodeling that demands a multidimensional, panoramic view to take into account all possibilities in lipid pathway analyses. Herein, we discuss current efforts undertaken to address these challenges, as well as alternative form of "pathway analyses" that may be particularly useful for uncovering functional lipid interactions under different biological contexts. Consolidating lipid pathway analyses will be indispensable in facilitating the transition of lipidomics from its prior role of phenotype validation to a hypothesis-generating tool that uncovers novel molecular targets to drive downstream mechanistic pursuits under biomedical settings.A new strategy for the fluorescent and colorimetric sensing of hydrogen peroxide (H2O2) and glucose based on the metal oxide - carbon-dot hybrid structure was investigated. The sensing system is related to the catalytic oxidation reaction of glucose-by-glucose oxidase (GOx) to H2O2. In this study, a metal oxide hybrid with nitrogen-doped carbon dots (MFNCDs) that showed intrinsic peroxidase-like activity was synthesized and used as a catalyst instead of GOx to oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to blue-emitting oxidized TMB (oxTMB) in the presence of hydrogen peroxide (H2O2). The fluorescence of MFNCDs/TMB at 405 nm was quenched in the presence of H2O2 through the inner filter effect (IFE) and electron transfer within MFNCDs, oxTMB, and glucose system. Therefore, the fluorescence and absorbance intensity can be applied to the quantitative determination of the concentration of H2O2 and glucose with a wide linear range. The detection limit for H2O2 and glucose based on the colorimetric method were as low as 84 nM and 0.41 μM, respectively. In contrast, the detection limit for H2O2 and glucose based on the fluorescent method were as low as 97 nM and 0.85 μM, respectively. Furthermore, the colorimetric readout on the paper device based on the changing color of the solution could also be integrated with a smartphone platform to conduct the on-site analysis of glucose without the use of the spectrometer. In addition, this dual sensor can be applied to detect glucose in real serum with highly accurate results, making it a good candidate for biosensor applications.Celiac disease is a complex and autoimmune disorder caused by the ingestion of gluten affecting almost 1% of global population. Nowadays an effective treatment does not exist, and the only way to manage the disease is the removal of gluten from the diet. Owing the key role played by gluten, clear and regulated labelling of foodstuff and smart methods for gluten detection are needed to fight frauds on food industry and to avoid the involuntary ingestion of this protein by celiac patients. https://www.selleckchem.com/products/bms-986020.html On that scope, the development of a novel detection system of gluten is here presented. The sensor consists of nanoporous anodic alumina films loaded with a fluorescent dye and capped with an aptamer that recognizes gliadin (gluten's soluble proteins). In the presence of gliadin, aptamer sequences displace from the surface of anodic alumina resulting in pore opening and dye delivery. The dispositive shows a limit of detection (LOD) of 100 μg kg-1 of gliadin, good selectivity and a detection time of approximately 60 min. Moreover, the sensor is validated in real food samples. This novel probe allows fast gluten detection through a simple signalling process with potential use for food control.A fluorescent sensing strategy was developed for rapid, highly sensitive and specific detection of lead (II) ion (Pb2+) on the basis of Pb2+ DNAzyme-controlled tetrahedral DNA nanostructure (TDN)-mediated hyper-branched hybridization chain reaction (hHCR). In this strategy, DNA hairpins used for HCR amplification are modified on the four vertexes of TDN, which are then used to perform rapid TDN-hHCR in the presence of an initiator strand, producing large-sized cross-linked reaction products and thus giving greatly improved fluorescence resonance energy transfer (FRET) signal output. Pb2+ DNAzyme catalyzes the cleavage of the initiator strand, inhibiting the initiation of TDN-hHCR and giving decreased FRET signal. Synergetic signal amplification of Pb2+ DNAzyme-catalyzed cleavage reaction and subsequent TDN-hHCR confers the sensing platform with ultrahigh sensitivity. As low as 0.25 pM Pb2+ can be detected by using either signal "turn-on" or "turn-off" mode. The whole detection process can be finished within 20 min. Strong anti-interference capacity of FRET-based ratiometric detection and high specificity of Pb2+ DNAzyme endow the sensing platform with great practical application potential, which was demonstrated by the accurate detection of Pb2+ in real river water, fruit, vegetable and grain samples.The use of a piezoelectric tube for the photoacoustic gas-phase determination of NO2 as a model analyte is demonstrated. The tube is made from lead zirconate titanate with 30 mm length and 5.35 mm internal diameter. Its inner and outer surfaces are coated with electrodes. The tube serves as both, resonance body and transducer. The design is thus simpler than the usual combination of resonance tube and microphone as the two functions are embodied in the same component. The main resonance frequency of the tube was found to be 5341 Hz. A blue laser diode emitting at 450 nm was employed as light source for the determination of NO2. The limit of detection was determined as 83 ppbV and the calibration curve was linear with a coefficient of determination (r2) of 0.9998 up to the highest concentration of 15 ppmV tested.