Highly sensitive electrochemical determination of rutin based on the synergistic effect of 3D porous carbon and cobalt tungstate nanosheets

Rutin,a flavonoid found in fruits and vegetables,is a potential anticancer compound with strong anticancer activity.Therefore,electrochemical sensor was developed for the detection of rutin.In this study,CoWO_(4) nanosheets were synthesized via a hydrothermal method,and porous carbon(PC)was prepared via high-temperature pyrolysis.Successful preparation of the materials was confirmed,and characterization was performed by transmission electron microscopy,scanning electron microscopy,and X-ray photoelectron spectroscopy.A mixture of PC and CoWO_(4) nanosheets was used as an electrode modifier to fabricate the electrochemical sensor for the electrochemical determination of rutin.The 3D CoWO_(4) nanosheets exhibited high electrocatalytic activity and good stability.PC has a high surface-to-volume ratio and superior conductivity.Moreover,the hydrophobicity of PC allows large amounts of rutin to be adsorbed,thereby increasing the concentration of rutin at the electrode surface.Owing to the synergistic effect of the 3D CoWO_(4) nanosheets and PC,the developed electrochemical sensor was employed to quantitively determine rutin with high stability and sensitivity.The sensor showed a good linear range(5-5000 ng/mL)with a detection limit of 0.45 ng/mL.The developed sensor was successfully applied to the determination of rutin in crushed tablets and human serum samples.

Metabolic Pathway of Monounsaturated Lipids Revealed by In-Depth Structural Lipidomics by Mass Spectrometry

The study of lipid metabolism relies on the characterization of the lipidome,which is quite complex due to the structure variations of the lipid species.New analytical tools have been developed recently for characterizing fine structures of lipids,with C=C location identification as one of the major improvements.In this study,we studied the lipid metabolism reprograming by analyzing glycerol phospholipid compositions in breast cancer cell lines with structural specification extended to the C=C location level.Inhibition of the lipid desaturase,stearoyl-CoA desaturase 1,increased the proportion of n-10 isomers that are produced via an alternative fatty acid desaturase 2 pathway.However,there were different variations of the ratio of n-9/n-7 isomers in C18:1-containing glycerol phospholipids after stearoyl-CoA desaturase 1 inhibition,showing increased tendency in MCF-7 cells,MDA-MB-468 cells,and BT-474 cells,but decreased tendency in MDA-MB-231 cells.No consistent change of the ratio of n-9/n-7 isomers was observed in SK-BR-3 cells.This type of heterogeneity in reprogrammed lipid metabolism can be rationalized by considering both lipid desaturation and fatty acid oxidation,highlighting the critical roles of comprehensive lipid analysis in both fundamental and biomedical applications.